Ideally it's good to strip down the engine of any classic/vintage bike at intervals to example for the inevitable wear/failure that naturally occurs over time. There will always be metal fatigue with engine components. You discovered some ugly bodges you will only ever notice by stripping down. It's better to discover them before your bike seizes, as seizure can be fatal. for your bike and yourself. Older bikes often have oil problems and it is wise to replace bolts and gaskets more frequently than with modern bikes. That bolt/screw missing on the top of the carb is difficult to reconcile - regular maintenance and inspections mitigate against this type of problem. It must be said I've had bolts disappear from older bikes I bought second hand by virtue of the way some old engines vibrate in the frame more than modern bikes do. Lovely bike. Great video thanks Adrian.
I'm thinking the same. After you found the mistakes on the outside of the engine, you could've assumed that the rest of the engine also has a lot of bodges.
Who of us didnt bodge things in the 60s and 70s when these bikes were worth little and money was short for proper repairs. Certainly it brings back memories of my Ariel NH , but luckily when the head gave problems my father bought me the last new head that Writer's had in stock. Happy carefree days at college in the early 70s, i miss being young and immortal!😉
@@t20racerman nowadays I would have no thoughts but to make a new oversize valve guide or sleeve a stripped thread or drill out a broken bolt but he bought it without telling me in advance and who was I to argue.🙂
As a lad in the 1960s, I had a succession of such bikes that had been bodged, butchered and neglected. As you say, they were worth little at the time, and when we lads got them, they were essentially the, worn out, discarded, ride to work transport of the working man. I did my share of wrecking, stupidly using ill-fitting open ended spanners during needless strip downs, and meddling. My greatest occasion of sin was my obsession with 'de-coking' engines that before I got started on them, ran perfectly well enough. That and neglecting ever to change the oil on the grounds that it seemed to change itself by leaking copiously from a range of engine case joints. Oh - and squirting gasket sealer into joints in huge amounts and blocking oil ways. I had no idea and listened to people of my age or near it who knew no more than I did.
@@Tonyv1951 You and many others did damage, but the bikes were then of little value, not wanted, and without people doing there best to keep them going, they wouldn't have survived to this day!
@@Tonyv1951 reminds me of a journalist I knew, who related a tail of going to a petrol station with attendants, if you remember those days, and askiing for a pint of oil for her Norton, he is supposed to have said, "shall I pour it down your trousers now or would you like it in the bike first?"
This reminds me of one of the biggest sighs of relief I have with my much younger bike (42 yr old)... Taking parts off to clean and fine tune, and not seeing any signs that anyone has been that far inside it before me!
@@t20racerman don't get me wrong, exterior parts were all messed up! Wrong mudguards front and rear, terrible repaint, mirrors with imperial thread bolts braised onto the bottom of them forced into the metric threaded hand grips... *shudder* But at least the engine and gearbox were unmolested, and fired up after I'd rebuilt the carbs.
Hi I was out today (and again tomorrow for sure!) on my `37 RH500 I love it ,but my piston is not suffering a lack of space! When I saw the Allen bolts I had a bad feeling! what an animal! One thing , your piston looked quite new ? some modern pistons are not ground oval . This process is essential otherwise the piston "becomes" oval when hot, due to the unequal mass around the gudgeon pin growing more ,leading to hotspots and seizure. When the bore is done and everything's clean ; pop the piston in ,and with your feelers , make sure there is greater clearance at the sides of the skirt in the bore, if it`s equal this could be your problem. Anyway ,as long as the bottom end is sound no worries! (are pistons available? ),nothing "beyond the wit of man" she`s lovely good luck! Don`t forget to clean the "sludge trap"!
It was a new piston - that's what the previous owner told me. The bore though was tapered and far too tight, so no wonder it nipped up on me. Will clean out the sludge trap, and considering stripping the whole lot down 🙄
She's a beauty. She may be telling you that she wants to retire and strike a pose in a museum somewhere to be admired by all. Very nice job on the upkeep.
For prevention sake on old motors, its often worth running a bit of two stroke oil in the fuel - a weak ratio, just enough to assist friction between bore and piston. If the engine isn't run that often, then a bit of a shake of the bike/tank side-to-side before setting out is a good idea. Then motoring will usually keep it mixed from then on.
Yep. Premix in old four strokes makes a difference. It was common to do this on short circuit bikes back when JAP was the motor of choice. Especially when running A. Also, oil rings were not used.
@@bruceparr1678 It might be a good idea to increase the jet size if you mix in oil as the oil displaces fuel...so the actual fuel to air ratio leans out? No oil=all fuel Some oil=less fuel
The close top tube isn’t all bad news. I had a 500 Ariel with an alloy head more than fifty years ago with lots of manky threads. One day the exhaust rocker box broke loose and I got home by jamming a bit of wood between box and frame. I feel a bit embarrassed to admit it now!
Whatever keeps the oil where it belongs. A friend went to Syria by 650 twin Yamaha in the eighties. She broke the rev-meter shaft right where it exits the engine on a particularly bad piece of gravel road - oil spilled, there was no time to lose and she put in an old, seasoned barkless pine-twig she found on the spot. It swelled tight with the oil within an hour and kept everything separated (oil and atmosphere, that is) for over twenty years until the engine got a thorough overhaul - and the rev-meter back working.
Beautiful bike, great video imagery clear explanations!! Very troubling previous owner maintenance, borderline reckless. I hope you can get the old girl up and running 100%. great bit of history in VERY capable hands-thank you
I’ve never knowingly met Mr Bodgit, but this is yet another example of his work! If anybody actually meets him, please give him a good kicking from me!
I know zero about bikes, but I clicked because I thought it looked interesting. Good luck getting it properly in spec and running. Looks like a labor of love. An expat watching in S Florida.
I am very glad I stumbled across your channel. Your video was excellent! I owned a 68 Triumph for my first bike, and thats how I learned to learned to work on bikes. Looking forward to the next!
Apart from the mechanical problems that you have come across I would agree with others that lean running and high speed running caused the overheating. Back in 1966 when I was a young fool with Norton ES2 500cc plus sidecar I got very close to doing the same thing. Coming out of London on the A40 late in the evening with the throttle wide open I happened to glance down and noticed the first foot of exhaust was glowing bright red with chrome flakes sparkling into the slipstream. Knocked 10mph off the speed and the colours went back to normal. Like your run, that extra speed brings all sorts of fearful things to the fore.
I agree it's a tad lean on the main jet (I'll go up a size) but I've now had the barrel/piston clearance measured accurately and it's way too tight. Add high speed, heat and a lean mixture and there's only one outcome! 😭
Greetings from New Zealand Adrian. I've just found you and within minutes of listening I knew you were someone well worth listening to. I've got a Matchless 500 single (1949/51) awaiting my attention so I'm sure you can imagine why your magnificent bike and what you're doing to it is of particular interest to me just now. 😊
Thank you 😊 I neglected my motorcycle TH-cam channel for a few years as I was busy with my Narrowboat one (@narrowboatadventures), but I'll be building it back up this summer. Hopefully a fair few more similar videos to follow 😊
This is Phil from Croatia. Yes, that is worrying about the head bolt threads as you don't really want a helicoil there. I still have my 1948 A7 engine in bits as I didn't manage to get a gasket set when I was in UK. I might have to buy some copper and make a head gasket. I did get a new set of rings, amazingly it is still on standard bore.
@@t20racerman Yes, they were the people who normally have gasket sets but were out of stock. Since Brexit it is a nightmare trying to get stuff posted to Croatia so that's why I waited until I was there.
Outside of my recent purchase of my 1967 BSA Starfire 250 single which has a monoblock carburetor. All of my other British bikes have a Mark 1 concentric because I know how to take it apart clean it goop it up and put it back together put the cable on it and it works so I'm only going to learn how to work on one carburetor.
I bought a 1955 Ariel 500 for $50AUD back in ~1970 when I was an apprentice at a big steelworks. I took the engine out and dropped it off outside our workshop late one night, and over the next day or two I totally cleaned, polished and rebuilt it. It ran like a clock and I eventually sold the bike for $150. If only I'd known what it would eventually be worth 😞
This video came up in my feed, very interesting. My father ran and trialled an Ariel 500 in trials trim, in the late 50's and early 60's. Had to sell it when he got married! No idea what engine and frame it had. Will ask him next time I speak to him.
G'day from Australia mate, you have your hands full with this one, sad to say but all that lovely cast iron is only good for door stops now. You can try & repair it but you will always be chasing your tail mate. See what owners clubs have sad some people should not be allowed near a wheelbarrow even it has too many moving parts keep up the good you'll get there cheers.
It'll get repaired one way or another. So many abused engines on these old bikes, but without people like me, determined to put them right, we'd have a lot less old bikes out there :-)
Well at the very least you have found the issue . I guess giving it a touch more on the way home allowed the piston to swell a tad too much . On the plus side as you said the engine never ran properly or at all when you got the bike at least now you will know the barrel head and top end once repaired will be sorted out. Properly. . A nice informative video at a leisurely pace . I wish you well in the rebuild. Cheers
Thanks. When I measured the piston clearance it was far too tight, and the bore was tapered too. As for the head bolts... 😱😱 It will get sorted though, one way or another
Had the same issue over 50 years ago on my VH aluminium head and barrel first noticed oil stopped then observed rocker box going up and down. I was just a lad but fortunately my dad worked at Hatfield polytechnic college so they had everything to fix it. Personally I would go through the bottom end because I want to see it🤓
Once your barrel got too hot, your piston ring end gap expanded which caused it to seize up! After cooling down, the gap opened up so that it would turn over, you could ride on to your home. End gaps for these should be 10 thou. Have fun.
When it gets hot the rings expand, and the gap will close up, not expand. If the gap gets bigger then compression suffers.. If the gap closes then the engine seizes.
What a superb overview and video. For once you show all the real world glitches that seem to face the home repairer, and there were more than a few in this case. I have liked and subscribed. Well done.
The mixture is on the lean side, but not too lean to cause overheating to the extent it would seize up. Mine kept nipping up during the first 2000 miles because the firm that rebored it gave it the same clearance as a modern engine that was too tight, which is my guess anyway, and this may well have been the issue with yours. Remember that the top of the piston is narrower than the bottom as it runs hotter.. As for the untold bodgery, there are lots of animals out there that shouldn't be let loose with tools, especially as all the correct fittings for these engines are very easy to find.. Just polish a few thou off the piston and rehone the bore and start the running in process again. I didnt even have enough space to wiggle the rocker boxes off without pulling front engine bolt out.
@@t20racerman In my view the mixture is too lean at high revs. Tight piston no help there either. I would be checking the needle profile - main jet seems fine at low to middle revs but lean up high, so you could perhaps raise the needle, or fit one with a thinner diameter in the high range. I had a similar issue many years ago with three 1 3/4" SUs - the engine would idle perfectly, run beautifully up to 3,500rpm, then lean out above that. Spent hours in the SU needle catalogue to find the needle I thought would suit, then had to order them from the UK to be sent to me in Tasmania :) Luckily they were perfect, just a smidge on the rich side all the way to redline from 3500rpm.
Hi Adrian, a very interesting video. I bought an Atlas 750 many years ago and the head was secured with Allen keys that had a very coarse thread. They made it very difficult to torque down the head accurately. I don't think the missing screw from the top of the carb is going to make any noticeable difference. Air can get in around the cables and increases as they become slacker over time and wobble about a bit. If you are going to remove the scuff on the piston don't use emery cloth or sand paper use a fine file. Regards Edward
Thank you. Glad you enjoyed it. My head bolts are 7/16 x 18 BSF threads which will make fine torquing of the head somewhat difficult! Not ideal, but at least they are all in reasonable condition. Ran a tap down them and they cleaned up nicely. Have to work with what I've got now.... New bolts on order.
I had an RD350LC with a set of Wiseco pistons in it that seized on me at top speed. Like you I whipped the clutch in and pulled off the road. Anyway, the reason I posted this is that I had the SAME vertical stripes in the bore (and on the piston). Speaking to the engineer who bored the barrels, the clearances were a bit tight and when it was at full song, it heat seized. Hope this helps.
If the machine shop was worth it's charges they would have increased the clearances for an aircooled engine. I have a 1968 YG5-T 80cc that was overbored one size over (0.25mm..?) and the shop that did it mostly bore car engines and hadn't factored in the need for looser clearances because of the hotter running conditions, So it had some beginnings of a soft seize when running fast. Also running a smidge richer on the oil injection, and a slight increase in main jetting and raising the metering needles during break in. Good things to do.
As soon as I saw the red gasket cement I knew there'd be problems. So many simple errors in the engine rebuild. Of note too is the lack of good honing crosshatch markings - essential for holding particles of oil and allowing the piston and rings a smooth passage over them.
My father loved Ariel 500cc Red Hunters and used to race Ariels in his younger years, then restoring them in his later years. He always told me a story of a locally (Australian) cast replacement piston that was to be avoided as they expanded in the bore over time. The big joke was to say that the company had adopted a local department store motto of "while we live, we grow!" Hoping whoever did the previous rebuild, didn't use one of those pistons!
I'd checked it a few times before, although not on a proper 'plug chop', and it was absolutely fine. Definitely a tad weak on the main jet though it seems. I'll go up from a #200 to a #210 when I rebuild it. 😊
We ran into the same problem with a triumphant taking with a bottle and was a ninet 66 or 67 the head all eyed ball bolts and everything like that so we had to go through and retap everything Healy coral a bunch of them we didn't have any cracks but we will always. Make sure that we apoxied areas that we thought that was bad and then rebuilt it growing grown it down and everything like that so yeah Ben they're done that too many times.
Can't remember to much but I had a similar chassis with a twin port 350 engine. With an alloy barrel. Trials tyres. Lights. Nice bike. Oh it had flutes on the silencers. I have no idea if it was a special or original.
Glad you found me! 😊 Classic bikes really are wonderful, but you have to be prepared to do a bit of maintenance. Have you seen my "A fast thrash in the countryside on a BSA" video? So nice to ride. Will be filming another video today - out on my BSA. 😊
@@t20racerman I will hopefully take a look later on on the big TV. Just trying to edit my own little vid from Prescott at the moment and there were some amazing classic bikes being put through their paces on the hill.
I think the best option for the engine is to start again and rebore it and have a new piston and rings. For the mismatched threads either go for Helicoils or the solid type, ( I can't remember their name) so you can get things on and off with no problem. I hate bloody people who will just bodge things instead of doing it properly. God if you are going to put bigger bolts in because the threads have stripped, at least put a tap of the correct size in the holes !
The solid inserts are called Time-serts. Brilliant solution, but not available in the 5/16 x 26 size I need for the rocker cover bolts. I can helicoil the stripped one though. The cylinder head bolts are way bigger than standard - 7/16 x 18 and the barrel threads can't be helicoiled back to standard from that size. I'll have to work with what's there.
@@t20racermanif you have enough room making your own "timesert", ie a solid I'd and od threaded insert is an option. Best to use the same pitch inside and out and careful alignment when screwcutting the od or you have to make the insert overly large to allow for a mismatch in threads, but still possible. Metric threads are easier this way as taps are often available in the next size or two up but with the same pitch just like BSB or Cycle. Loctite 648 is good enough to hold the insert in place to give the same effect of the timesert's swaging feature.
@@t20racerman Wurth Timeserts are only quoted in metric. The closest metric equivalent to 5/16 x 26 would be M8 x 1.0 if they were available. I think the timeserts would have been the favorite repair for the regularly removed bolts but you are stuck with Helicoil. Helicoil would be the favorite for those bolts that did not require regular removal like the head bolts To stop the Helicoils from winding out peen the edge of the thread hole, still allowing the bolt to start in the thread. You can't use Loctite as this would ooze through the threads to lock the bolt as well Personally, as you have damaged threads all round (the tight bolts will have damaged threads) I would bite the bullet and Helicoil the lot, its just not worth skimping. A Helicoil is far stronger than a straight tapped hole due to its oversize and method of locking under load so Helicoiling the lot will be of benefit, they should not be considered as a repair but an upgrade. As for the head bolts just stay with the 7/16 x 18 with Helicoils as you have already stated that perfect authenticity is not the goal but using the machine is. I would have suggested scrapping the bolts and refitting with studs and nuts to get the most reliable arrangement since currently the tapped holes are into castings that doesn't lend itself to frequent dismantling but I appreciate that unless you remove the engine each time for a head removal or a valve check then the stud route is not practical. I see that the exhaust valve appears somewhat large. Normally for best gas flow the exhaust valve is sized at 85% of the inlet size and where this occurs elsewhere the opportunity to increase the inlet valve size (only) has netted advantages. Is the piston OE because the bore is worn, as you say with a lip but it is too tight at the bottom. The piston is for the most part scrap as the ring land for the middle ring is crushed so a new oversized piston in a rebored cylinder will probably be required. I would shoot for 5thou per inch of bore for the ring gap for an air-cooled engine and 1.5thou per inch for the piston clearance as they are prone to large fluctuations in temperature
@@clivewilliams3661 Someone good advice there. I'm definitely going to leave the head bolt size as 7/16 x18 as the threads cleaned up really nicely, although I'd have preferred a finer thread. Re the rocker cover bolt threads, I'll see what threads can be reused , and find a solution for the others. It's a shame it's such a mess, but all can be made good one way or another 🙂
Found that really interesting and informative. Lovely bike. I have a '59 C15 which is not so impressive but I love it despite its extensive oil leaks! Al the best sorting out after that butchering. Some people should not be allowed to touch a bike engine.
Thanks, glad you enjoyed it. Yes, it'll take some sorting, but hey ho, if we're going to buy and ride motorcycles from decades ago, we have to expect these things I guess. 😊
Hi Adrian, from one ex racing shed dweller to another, as troublesome as these are, these are the things that keep us sane. Would you consider just re-helicoiling every available thread you get to over to metric, just purely on the better availability of bolt materials, threads and sizes. I've done this before on rebuilds and paint marked each of the bolt groups ie R/cover, head, barrel, side casings, as I went and added to it on each subsequent strip down until all the bolts are metric. Unless I was wanting an original rebuild it works out easier in the long run.
I'm not mad on the idea of moving to metric. I'll assess everything carefully and work out the best solution - best as in effective and not too expensive. As you would know from racing - what works is what you do! 😁
the bore condation you cant say happen when it seized up.. iam sure some did. but with what you said about the bolts. iam wondering what bore issues were there before hand. sad when folks damage motors puttin them togther ...
When I began riding in the 60s there were many more experts available, sadly time has removed them. When I took a badly butchered B33 engine to our local BSA doctor, for advice, he knew who had worked on it, and his comment was "That bastard should have his tools confiscated and be issued with a cast iron side valve".
Hi folks, way off topic but in my much younger days I used to dream of owning an Airel Leader. Liked fairings even then! Seem to remember that one reviewer rode one from Scotland to London in the rain and claimed not to have got wet.
@@t20racerman All depends on how long you actually run on the main jet. irc a freind back in the late 70s with a B25 starfire said in was runnining the best it ever did moments before the piston smeared itself around the barrel.
@@kevinwilliams4899 On my racing 2-strokes, if ever they ran superbly flat out, you'd worry - and re-jet after the race if it survived. Had to have a barometer in the tool kit because if the air pressure dropped, you'd seize up unless you re-jetted. Crazy times!
I presume that's a pattern piston possibly from Australia. I used one made in Italy on my ajs. The ozy ones are prone to seize up as there made out of the wrong alloy.
Hello there, this might be obvious but with all that bodgery in the top end I would be worried about the rest of the motor. I used to have a bike salvage yard here in the States and the things I have seen, especially to old British Bikes, still give me nightmares.
Hi Adrian , from Québec. Looks like you'll need new threads , new bolts , everywhere. With sizes 1/4 , 5/16 , 3/8 , I'd have no idea where to go up in size , then find the proper bolts ! As to heli-coils , I find those on the market a bit short of threads. Hmmmm... I say that not knowing exactly what sizes your bolts are , of course . I've done my Kawa's 16 M6 cam bolts going to longer 1/4-20 ones no problem , just using a 13/64 drill then the hand operated tap --just beeing very careful.
English bikes are lovelly. I had a 1932 Favor, with a Jap 250cc engine. Interesting fins on the admission pipe, I've never seen this. I miss my XT500 :) The mix of metric and imperial makes no sense. There are fine thread metric, 1.0.
A friend of mine had a Triumph T90 which had been rebored n new pistons but it too kept seizing and the only cure was to run it on Duckhams Q 20/50 no more seizures !
Hi Folks, I'm a silver haired ex Norton owner. I've stripped one of those and rebuilt it but am not Aerial novice, let alone an expert. However .....6:35. That's a BIG air leak. 11:00 Normally a corse thread is used into cast iron, a fine thread is more suitable in aluminium. I think this has been bodged.
Yup, quite a big air leak! The threads on these should be: 3/8 x 26 for the head bolts and 5/16 x 26 for the rocker cover bolts MY head ones are 7/16 x 18 BSF which is quite a difference.
A Layman's take (and I'm not even going to put thought into this, so as casual as can be).. Considering how difficult finding B.S.C. replacements must be by now, especially good condition and hearing you mention making the bolts, how unpopular would you be switching to M8 ..and might you mitigate this at all by re-cutting modern bolts (socket head or otherwise)?
I'll probably have a couple of M8s where the damaged rocker cover bolt threads were. Will look at putting in time-sert inserts. The head bolt threads in the cylinder have already been opened up to a bigger size, and I can't change them now. They cleaned up ok, so I'll use them - but with decent bolts to hold the head down
@@t20racerman That sounds right dis similar heating considered, had a 500 International with cast barrel. I have used the daily runner 441 36 years or so many barrels LOL! Wish they were more like my 72 R60/5 swb barrel wise.
That broken head is due to blind hole hydraulicing. There has been oil in the blind hole and someone has tightened a bolt down on it causing it to explode.
The previous owner sold me his toolkit. It was a bowsaw, vise-grips and a heavy rock. In fairness, he didn't charge me for the bowsaw because "it doesn't work properly" but it was fine when I switched the blade right way up!!!
I would say plug is wrong grade for 'high speed' use, probably have a 'soft' plug fitted for trials use? Correct grade will show a definite 'line' on the ground strap (not a lot of people seem to know that) Otherwise, colour doesn't seem too bad with unleaded fuel. Does it have alcohol in it? (in USA E-10 is norm, instead of feeding animals or humans, they turn corn into ethanol) I was thinking screw missing from carb top wouldn't have much effect until I saw you had a Monobloc on there. Never been a fan of them or Concentric's Apart from separate float chamber having some 'issues' on sidecars when cornering, the older type was a much better carb in my opinion. You could use a smaller size and get same or better airflow ( the Japanese versions eventually got developed into Mikuni 'smoothbore' classed as a 'racing' carb) Is that an A7 or A10 in background? I've got a '52 A10 plunger with 'sidecar' primary (duplex chain) I was expecting wrong bolts fitted when you said previous owner had done 'cosmetics'. Probably only ever seen metric bolts and never heard of Whitworth, BSF, BSC, Cycle, B.A. etc. (don't remember if Ariel use their own threads like Triumph?) Tight threads - common problem. Probably fitted UNF 60 degree thread instead of correct BSF 55 degree thread angle? I would tap cylinder for a standard size bolt (probably 1/2" or even a metric?), make some inserts and go back to original bolts (one thing I've always hated is mix and match , metric on metric bikes, inches on British bikes) Those 'lines' in cylinder are from gudgeon pin, seen it before (worst was a Jubilee Bonneville when I worked at Honda/Triumph dealers, Meridan forgot cir-clips and wore a slot between cylinders)
Some very interesting comments there, thank you. A colder plug is certainly something to consider, although when I've checked it other days (albeit not a proper plug-chop) it's looked spot on. I'll definitely go up a main jet. Having UNF head bolts in BSF threads sounds plausible as I found the barrel threads cleaned out lovely with a BSF tap, but a die on the Allen bolts (just to see) was very tight, despite being the correct size. Yup, it's an A10 - a pretty special one. Check out my BSA playlist to see more. I'm also relaunching this channel, so more BSA vids (along with other stuff) coming soon. 😊
That plug doesn’t look all that bad to me. Maybe a touch lean given the very light tan color, but it wasn’t bleached out white which one sees on a plug that is obviously the wrong heat range or in a very lean running engine. I might try to get a plug one heat range colder, but otherwise I wouldn’t worry much based on that plug alone. I am writing this only a few minutes into your video so I am curious to see what comes next.
Well done you. Just a thought, as I ran into something similar many, many years ago, is the piston in the right way round ? Good luck and I truly hope you manage to helicoil everything tickety boo.
I like the quality of this video. Sounds like this bike went through some dodgy owners. Be prepared for more mischief. I've been through it enough now that I ask more about the owner than the bike when purchasing.
Thank you 😊. Yup, some dodgy work on this bike over the years. They weren't valued as classics though back then, just an 'old bike' that needed fixing (somehow!) to get hit going again. Bound to be the odd dodgy repair over it's 74 year life 🙁
Motorcycle mechanic by trade and 2 bobs worth. I've seen many overtight rebores from engine reconditioners. I've seen many loose clearance engines running perfectly well. Just scrape any aluminium that's adhered to the bore and hone. Replace the rings. Clean up the piston if it's OK. Air cooled engines get hot, really hot. They need clearance.
It is hard to believe some of the butchers who do vintage resto's. One chap admitted to me that he did not even put new bearings into the bikes he was restoring because none of his customers ride them very much.
@@t20racerman ok, didnt know that. I assume you are trying to keep the bolt sized stock? Even though the bike is kinda not ? Personally I would just change to metric. Specially as most would never know. But either way, hope you success.
I can't believe someone just decided to stuff the wrong sized threads in! Who owns an old machine and doesn't bother to figure out what the correct thread is?
It took some work to get it going I must admit. It's run beautifully since though (apart from seizing!), so I'll build the top end back up, use the it through the summer and have a look at the rest in the winter. But yes, no big sense of confidence in the rest of it! 😬
Ok, towards the end. Hmm, I think I would go with helicoil inserts. Those head bolts are a critical component and need to be of the correct material and quality. All bolts are not created equal! Just make sure there is enough 'meat' around the inserts. Liked and subd.
I don't think helicoils will be strong enough for the head bolts - but fine for the rocker cover bolts. The cylinder threads cleaned up nicely - they've been taken up to 7/16 x 18 BSF by a previous owner, and although 18tpi is a little too course for head bolts, I'll use what's there if it works
I'm definitely going up a size on the main jet. It was fine for the rest of of the range. The piston clearance was the main issue though - a tapered bore and far too tight!
Oh dear, a real mess. I hope you went round and put Helicoils in all the threads. Sounds like some klutz really had a field day with it!🤔 Also, be aware that fitting a spacer on the carb means your mixtures will be different from the specs. P.S. Is that a Rocket Gold Star behind the Ariel?
I'm still working on the best solution for the threads. I love Time-serts as they are SO good, but cycle threads not availiable, whereas helicoils do come in the correct thread sizes The BSA is a heavily modified A10. I'm releasing a video of it this afternoon - thrashing it around the countryside! More to come. Also, do check out my channel playlists as there are a few of my BSA..
Looks lean to me. The plug earth side is light all the way back to the thread and the centre is a bit 'pinky'. Black around the thread, dark colour on the earth and a tan or darker brown on the electrode would be much happier. From the general combustion chamber carbon it absolutely isn't rich for sure.
That's what I think. I'd checked the plug a few times before and it was spot on - but those times it was not a proper fast, main jet test, plug chop. It was clearly weaker on the main jet than through the rest of the rev range. I'll go up a size
"The rocker horror picture show".
Good luck with the repair!
Horrendous isn't it? 😕
Ideally it's good to strip down the engine of any classic/vintage bike at intervals to example for the inevitable wear/failure that naturally occurs over time. There will always be metal fatigue with engine components. You discovered some ugly bodges you will only ever notice by stripping down. It's better to discover them before your bike seizes, as seizure can be fatal. for your bike and yourself.
Older bikes often have oil problems and it is wise to replace bolts and gaskets more frequently than with modern bikes. That bolt/screw missing on the top of the carb is difficult to reconcile - regular maintenance and inspections mitigate against this type of problem. It must be said I've had bolts disappear from older bikes I bought second hand by virtue of the way some old engines vibrate in the frame more than modern bikes do. Lovely bike. Great video thanks Adrian.
Some good points there, and I agree with you - I feel I need to strip all of the engine down to see what other horrors await... 😬
i can see why you like the bike, it's a beauty. it's clearly in good hands.
Thank you. 😊
Great teaching
With the bodges you've uncovered so far it would be madness not to strip the whole engine and start from scratch !
Thinking the same myself 😕
I'm thinking the same. After you found the mistakes on the outside of the engine, you could've assumed that the rest of the engine also has a lot of bodges.
Who of us didnt bodge things in the 60s and 70s when these bikes were worth little and money was short for proper repairs. Certainly it brings back memories of my Ariel NH , but luckily when the head gave problems my father bought me the last new head that Writer's had in stock. Happy carefree days at college in the early 70s, i miss being young and immortal!😉
A new head... Nice! 😁
@@t20racerman nowadays I would have no thoughts but to make a new oversize valve guide or sleeve a stripped thread or drill out a broken bolt but he bought it without telling me in advance and who was I to argue.🙂
As a lad in the 1960s, I had a succession of such bikes that had been bodged, butchered and neglected. As you say, they were worth little at the time, and when we lads got them, they were essentially the, worn out, discarded, ride to work transport of the working man. I did my share of wrecking, stupidly using ill-fitting open ended spanners during needless strip downs, and meddling. My greatest occasion of sin was my obsession with 'de-coking' engines that before I got started on them, ran perfectly well enough. That and neglecting ever to change the oil on the grounds that it seemed to change itself by leaking copiously from a range of engine case joints. Oh - and squirting gasket sealer into joints in huge amounts and blocking oil ways. I had no idea and listened to people of my age or near it who knew no more than I did.
@@Tonyv1951 You and many others did damage, but the bikes were then of little value, not wanted, and without people doing there best to keep them going, they wouldn't have survived to this day!
@@Tonyv1951 reminds me of a journalist I knew, who related a tail of going to a petrol station with attendants, if you remember those days, and askiing for a pint of oil for her Norton, he is supposed to have said, "shall I pour it down your trousers now or would you like it in the bike first?"
Nice video, real trials and tribulations of owning an old machine. I look forward to seeing detail of how you sorted all those bodges.
Thanks. Currently puzzling over some of it, but most is in hand... I hope! 😁
I'm sure that bike could tell you a few tales of the dodgy repairs over the years, that has been around a long, long time. Glad you are seeing to it.
Absolutely right. Certainly have been some bodges in its 74 year history.
It will be sorted though, one way or another 😊
This reminds me of one of the biggest sighs of relief I have with my much younger bike (42 yr old)... Taking parts off to clean and fine tune, and not seeing any signs that anyone has been that far inside it before me!
So nice 😁
@@t20racerman don't get me wrong, exterior parts were all messed up!
Wrong mudguards front and rear, terrible repaint, mirrors with imperial thread bolts braised onto the bottom of them forced into the metric threaded hand grips... *shudder*
But at least the engine and gearbox were unmolested, and fired up after I'd rebuilt the carbs.
Hi I was out today (and again tomorrow for sure!) on my `37 RH500 I love it ,but my piston is not suffering a lack of space! When I saw the Allen bolts I had a bad feeling! what an animal! One thing , your piston looked quite new ? some modern pistons are not ground oval . This process is essential otherwise the piston "becomes" oval when hot, due to the unequal mass around the gudgeon pin growing more ,leading to hotspots and seizure. When the bore is done and everything's clean ; pop the piston in ,and with your feelers , make sure there is greater clearance at the sides of the skirt in the bore, if it`s equal this could be your problem. Anyway ,as long as the bottom end is sound no worries! (are pistons available? ),nothing "beyond the wit of man" she`s lovely good luck! Don`t forget to clean the "sludge trap"!
It was a new piston - that's what the previous owner told me. The bore though was tapered and far too tight, so no wonder it nipped up on me.
Will clean out the sludge trap, and considering stripping the whole lot down 🙄
Such a beautiful bike… I swear it brings back the smell of hot Castrol oil I ran in my Triumph 250 back in the late 1970’s.
Thank you - It really is a lovely bike. 😊
She's a beauty. She may be telling you that she wants to retire and strike a pose in a museum somewhere to be admired by all. Very nice job on the upkeep.
Retire? Bikes are for go, not show! 😁
@@t20racerman Understandable. We don't see Ariel bikes much in the US. I don't think many were sold here if any. Maybe not as rare in the UK?
@@twwtb Used to be fairly common. Not like BSA & Triumph were, but still plenty around
Euthenase the critter so someone can practise taxidermy? Yuck!
For prevention sake on old motors, its often worth running a bit of two stroke oil in the fuel - a weak ratio, just enough to assist friction between bore and piston. If the engine isn't run that often, then a bit of a shake of the bike/tank side-to-side before setting out is a good idea. Then motoring will usually keep it mixed from then on.
Yep. Premix in old four strokes makes a difference. It was common to do this on short circuit bikes back when JAP was the motor of choice. Especially when running A. Also, oil rings were not used.
@@bruceparr1678
It might be a good idea to increase the jet size if you mix in oil as the oil displaces fuel...so the actual fuel to air ratio leans out?
No oil=all fuel
Some oil=less fuel
@@JohnSmith-yv6eq Only about 2% less fuel.
@@JohnSmith-yv6eq Leans it out by a similar amount as a 2000' increase in elevation.
It also clears out carbon deposits in the combustion chamber. 640:1 of TCW-3 two stoke-oil is the ratio to use in all four-stroke engines, even cars.
The close top tube isn’t all bad news. I had a 500 Ariel with an alloy head more than fifty years ago with lots of manky threads. One day the exhaust rocker box broke loose and I got home by jamming a bit of wood between box and frame. I feel a bit embarrassed to admit it now!
Whatever works and gets you home it's a great solution 😁
Whatever keeps the oil where it belongs. A friend went to Syria by 650 twin Yamaha in the eighties. She broke the rev-meter shaft right where it exits the engine on a particularly bad piece of gravel road - oil spilled, there was no time to lose and she put in an old, seasoned barkless pine-twig she found on the spot. It swelled tight with the oil within an hour and kept everything separated (oil and atmosphere, that is) for over twenty years until the engine got a thorough overhaul - and the rev-meter back working.
@@manfredschmalbach9023A brilliant fix 😊
Ive had to stuff my tire full of weeds when I got a front flat out in the bush. W/e it takes to get you home is Never a bad thing :) Cheers.
@@fetus2280 Not heard of that one before! 😁
Beautiful bike, great video imagery clear explanations!! Very troubling previous owner maintenance, borderline reckless. I hope you can get the old girl up and running 100%. great bit of history in VERY capable hands-thank you
Thank you 😊. Yup I'll get it sorted, maybe not as good as new, but sorted nonetheless 🏍️
I’ve never knowingly met Mr Bodgit, but this is yet another example of his work! If anybody actually meets him, please give him a good kicking from me!
You, me and many others too I believe having read through the comments!
Great teaching Aid.
Thank you 😊
Supernice bike, well worth fixing. It went to a good home clearly, it will be sorted correctly now. good stuff!
Thank you 😊
What a nice old school single, good luck with the repairs. I'm sure you will get there in the end.
Its a lovely old bike, and yes, it'll be back on the road soon enough one way or another 😊
I know zero about bikes, but I clicked because I thought it looked interesting. Good luck getting it properly in spec and running. Looks like a labor of love. An expat watching in S Florida.
Hi there 👋 Thanks for watching and I hope that you enjoyed it
I am very glad I stumbled across your channel. Your video was excellent! I owned a 68 Triumph for my first bike, and thats how I learned to learned to work on bikes. Looking forward to the next!
Thank you - and welcome along! Ariel repair video not made yet...as I still haven't repaired it! A BSA one coming shortly though 🙂
Forced in bigger bolts, the animal, poor Ariel has a good home now. Really well done video.
So many bodges! 😭
Glad you enjoyed my video. More to follow soon
Apart from the mechanical problems that you have come across I would agree with others that lean running and high speed running caused the overheating. Back in 1966 when I was a young fool with Norton ES2 500cc plus sidecar I got very close to doing the same thing. Coming out of London on the A40 late in the evening with the throttle wide open I happened to glance down and noticed the first foot of exhaust was glowing bright red with chrome flakes sparkling into the slipstream. Knocked 10mph off the speed and the colours went back to normal. Like your run, that extra speed brings all sorts of fearful things to the fore.
I agree it's a tad lean on the main jet (I'll go up a size) but I've now had the barrel/piston clearance measured accurately and it's way too tight. Add high speed, heat and a lean mixture and there's only one outcome! 😭
Greetings from New Zealand Adrian. I've just found you and within minutes of listening I knew you were someone well worth listening to. I've got a Matchless 500 single (1949/51) awaiting my attention so I'm sure you can imagine why your magnificent bike and what you're doing to it is of particular interest to me just now. 😊
Thank you 😊
I neglected my motorcycle TH-cam channel for a few years as I was busy with my Narrowboat one (@narrowboatadventures), but I'll be building it back up this summer. Hopefully a fair few more similar videos to follow 😊
Wow, Nice ride mate. Glad I found your channel. Thanks for the knowledge. Cheers.
Thank you. Next video out v shortly 😊
@@t20racerman Nice, looking fwd to it :)
This is Phil from Croatia. Yes, that is worrying about the head bolt threads as you don't really want a helicoil there. I still have my 1948 A7 engine in bits as I didn't manage to get a gasket set when I was in UK. I might have to buy some copper and make a head gasket. I did get a new set of rings, amazingly it is still on standard bore.
Hi there Phil - nice seeing you the other day 😊
Have you tried Draganfly in Bungay for the A7 bits? They have loads of stuff
@@t20racerman Yes, they were the people who normally have gasket sets but were out of stock. Since Brexit it is a nightmare trying to get stuff posted to Croatia so that's why I waited until I was there.
@@Phiyedough Happy to post them to you if Dragonfly send to me
I am always amazed the innovative ways Brit bikes can develop problems. They look lovely, but...
After several decades of use and abuse, it's amazing how many have survived this long! 😊
My first bike was a '47 VB 600 side valve, so you have my interest. Subbed.
Thank you 🙂
Very interesting Adrian.
@@flmulcahy Thank you. The bottom end was worse than the top end! ☹️
Outside of my recent purchase of my 1967 BSA Starfire 250 single which has a monoblock carburetor. All of my other British bikes have a Mark 1 concentric because I know how to take it apart clean it goop it up and put it back together put the cable on it and it works so I'm only going to learn how to work on one carburetor.
I've had monoblocs and concentrics. My A10 has had both fitted in the past. Its a concentric now. Both pretty straight forward carbs
Best of Luck. Good work.
Thank you 😊
I bought a 1955 Ariel 500 for $50AUD back in ~1970 when I was an apprentice at a big steelworks. I took the engine out and dropped it off outside our workshop late one night, and over the next day or two I totally cleaned, polished and rebuilt it. It ran like a clock and I eventually sold the bike for $150. If only I'd known what it would eventually be worth 😞
They are such nice bikes. 😊
This video came up in my feed, very interesting. My father ran and trialled an Ariel 500 in trials trim, in the late 50's and early 60's. Had to sell it when he got married! No idea what engine and frame it had. Will ask him next time I speak to him.
Nice! Maybe show him my video too - might bring back some memories 😊
G'day from Australia mate, you have your hands full with this one, sad to say but all that lovely cast iron is only good for door stops now. You can try & repair it but you will always be chasing your tail mate. See what owners clubs have sad some people should not be allowed near a wheelbarrow even it has too many moving parts keep up the good you'll get there cheers.
It'll get repaired one way or another. So many abused engines on these old bikes, but without people like me, determined to put them right, we'd have a lot less old bikes out there :-)
Plug looks spot on 😉
Not far off right. A tad weak on the main jet I feel
Well at the very least you have found the issue . I guess giving it a touch more on the way home allowed the piston to swell a tad too much . On the plus side as you said the engine never ran properly or at all when you got the bike at least now you will know the barrel head and top end once repaired will be sorted out. Properly. . A nice informative video at a leisurely pace . I wish you well in the rebuild. Cheers
Thanks. When I measured the piston clearance it was far too tight, and the bore was tapered too. As for the head bolts... 😱😱
It will get sorted though, one way or another
Had the same issue over 50 years ago on my VH aluminium head and barrel first noticed oil stopped then observed rocker box going up and down. I was just a lad but fortunately my dad worked at Hatfield polytechnic college so they had everything to fix it.
Personally I would go through the bottom end because I want to see it🤓
That was handy! Yup, I definitely need to inspect the bottom end.
Once your barrel got too hot, your piston ring end gap expanded which caused it to seize up! After cooling down, the gap opened up so that it would turn over, you could ride on to your home. End gaps for these should be 10 thou. Have fun.
When it gets hot the rings expand, and the gap will close up, not expand.
If the gap gets bigger then compression suffers..
If the gap closes then the engine seizes.
I've measured the ring gap and it's fine, but the bore is far too tight for the piston, and tapered too!
What a superb overview and video. For once you show all the real world glitches that seem to face the home repairer, and there were more than a few in this case. I have liked and subscribed. Well done.
Thank you. Glad you enjoyed it. But what a mess my Ariel is... 😢
this is a beautiful machine
Thank you - I agree. 😁
Just got to fix it now...
Its the first thing that came to my mind when you described the problem. Result of a cheapo repair by the previous owner to get some compression back.
He clearly had little mechanical skill 🙁
The mixture is on the lean side, but not too lean to cause overheating to the extent it would seize up. Mine kept nipping up during the first 2000 miles because the firm that rebored it gave it the same clearance as a modern engine that was too tight, which is my guess anyway, and this may well have been the issue with yours. Remember that the top of the piston is narrower than the bottom as it runs hotter.. As for the untold bodgery, there are lots of animals out there that shouldn't be let loose with tools, especially as all the correct fittings for these engines are very easy to find.. Just polish a few thou off the piston and rehone the bore and start the running in process again. I didnt even have enough space to wiggle the rocker boxes off without pulling front engine bolt out.
That's how I feel - it's a tad weak on the main jet and worth going up a size, but it's not weak enough to cause a seizure.
I’d say the plug colour is OK, certainly not weak but I might change my mind if I saw it in daylight!
@@t20racermanbut how often are you on the main jet?
@@raymondsanderson3768 Not that often, but I think going up a size would be advisable. Mixture seems spot on for the rest of the carb range 😊
@@t20racerman In my view the mixture is too lean at high revs. Tight piston no help there either. I would be checking the needle profile - main jet seems fine at low to middle revs but lean up high, so you could perhaps raise the needle, or fit one with a thinner diameter in the high range. I had a similar issue many years ago with three 1 3/4" SUs - the engine would idle perfectly, run beautifully up to 3,500rpm, then lean out above that. Spent hours in the SU needle catalogue to find the needle I thought would suit, then had to order them from the UK to be sent to me in Tasmania :) Luckily they were perfect, just a smidge on the rich side all the way to redline from 3500rpm.
It could be worth stripping the bottom end and get the big end checked and conrod for straightness so piston is running in the bore correctly.
Hi Adrian, a very interesting video. I bought an Atlas 750 many years ago and the head was secured with Allen keys that had a very coarse thread. They made it very difficult to torque down the head accurately. I don't think the missing screw from the top of the carb is going to make any noticeable difference. Air can get in around the cables and increases as they become slacker over time and wobble about a bit. If you are going to remove the scuff on the piston don't use emery cloth or sand paper use a fine file. Regards Edward
Thank you. Glad you enjoyed it.
My head bolts are 7/16 x 18 BSF threads which will make fine torquing of the head somewhat difficult! Not ideal, but at least they are all in reasonable condition. Ran a tap down them and they cleaned up nicely. Have to work with what I've got now.... New bolts on order.
I had an RD350LC with a set of Wiseco pistons in it that seized on me at top speed. Like you I whipped the clutch in and pulled off the road. Anyway, the reason I posted this is that I had the SAME vertical stripes in the bore (and on the piston). Speaking to the engineer who bored the barrels, the clearances were a bit tight and when it was at full song, it heat seized. Hope this helps.
If the machine shop was worth it's charges they would have increased the clearances for an aircooled engine. I have a 1968 YG5-T 80cc that was overbored one size over (0.25mm..?) and the shop that did it mostly bore car engines and hadn't factored in the need for looser clearances because of the hotter running conditions, So it had some beginnings of a soft seize when running fast. Also running a smidge richer on the oil injection, and a slight increase in main jetting and raising the metering needles during break in. Good things to do.
Yes, it was definitely a clearance issue on mine. Had it accurately measured up and it was way too small
You do have to be very careful when getting rebores done - as you say, old air cooled motorcycle engines aren't the same as water cooled engine cars
What a beautiful bike. My Dad had a Red Hunter during the war, commuted from Kits Coty to Chatham Dockyard on it.
@@TrustMeiamaD.R. Very popular bikes back in the day, and extremely reliable too 😊
sounds very nice!!!
It does, and it will again shortly 😁
As soon as I saw the red gasket cement I knew there'd be problems.
So many simple errors in the engine rebuild. Of note too is the lack of good honing crosshatch markings - essential for holding particles of oil and allowing the piston and rings a smooth passage over them.
It was tapered and far too tight too. 😕
My father loved Ariel 500cc Red Hunters and used to race Ariels in his younger years, then restoring them in his later years. He always told me a story of a locally (Australian) cast replacement piston that was to be avoided as they expanded in the bore over time. The big joke was to say that the company had adopted a local department store motto of "while we live, we grow!" Hoping whoever did the previous rebuild, didn't use one of those pistons!
Interesting. I hope not too!
I agree that plug looks like the bike had a lean mixture
I'd checked it a few times before, although not on a proper 'plug chop', and it was absolutely fine. Definitely a tad weak on the main jet though it seems. I'll go up from a #200 to a #210 when I rebuild it. 😊
We ran into the same problem with a triumphant taking with a bottle and was a ninet 66 or 67 the head all eyed ball bolts and everything like that so we had to go through and retap everything Healy coral a bunch of them we didn't have any cracks but we will always. Make sure that we apoxied areas that we thought that was bad and then rebuilt it growing grown it down and everything like that so yeah Ben they're done that too many times.
There are a lot of engines out there that have been butchered, sadly :-(
Can't remember to much but I had a similar chassis with a twin port 350 engine. With an alloy barrel. Trials tyres. Lights. Nice bike. Oh it had flutes on the silencers. I have no idea if it was a special or original.
Sounds nice. 😊
Hello from a new subscriber in New Zealand 🇳🇿
Hi there. Thanks for subscribing, and welcome to my little world 😊
@@t20racerman Awesome channel mate👍🏻
Very interesting video,subbed.
Thank you, and thank you 😊
Good video enjoyed it 👍
Thank you :-)
Hi, I just found your channel. It was a really interesting presentation. Don't own a classic bike but considering one.
Glad you found me! 😊 Classic bikes really are wonderful, but you have to be prepared to do a bit of maintenance. Have you seen my "A fast thrash in the countryside on a BSA" video? So nice to ride. Will be filming another video today - out on my BSA. 😊
@@t20racerman I will hopefully take a look later on on the big TV. Just trying to edit my own little vid from Prescott at the moment and there were some amazing classic bikes being put through their paces on the hill.
I think the best option for the engine is to start again and rebore it and have a new piston and rings. For the mismatched threads either go for Helicoils or the solid type, ( I can't remember their name) so you can get things on and off with no problem. I hate bloody people who will just bodge things instead of doing it properly. God if you are going to put bigger bolts in because the threads have stripped, at least put a tap of the correct size in the holes !
The solid inserts are called Time-serts. Brilliant solution, but not available in the 5/16 x 26 size I need for the rocker cover bolts. I can helicoil the stripped one though. The cylinder head bolts are way bigger than standard - 7/16 x 18 and the barrel threads can't be helicoiled back to standard from that size. I'll have to work with what's there.
@@t20racermanif you have enough room making your own "timesert", ie a solid I'd and od threaded insert is an option. Best to use the same pitch inside and out and careful alignment when screwcutting the od or you have to make the insert overly large to allow for a mismatch in threads, but still possible. Metric threads are easier this way as taps are often available in the next size or two up but with the same pitch just like BSB or Cycle. Loctite 648 is good enough to hold the insert in place to give the same effect of the timesert's swaging feature.
@@t20racerman Wurth Timeserts are only quoted in metric. The closest metric equivalent to 5/16 x 26 would be M8 x 1.0 if they were available. I think the timeserts would have been the favorite repair for the regularly removed bolts but you are stuck with Helicoil. Helicoil would be the favorite for those bolts that did not require regular removal like the head bolts To stop the Helicoils from winding out peen the edge of the thread hole, still allowing the bolt to start in the thread. You can't use Loctite as this would ooze through the threads to lock the bolt as well Personally, as you have damaged threads all round (the tight bolts will have damaged threads) I would bite the bullet and Helicoil the lot, its just not worth skimping. A Helicoil is far stronger than a straight tapped hole due to its oversize and method of locking under load so Helicoiling the lot will be of benefit, they should not be considered as a repair but an upgrade. As for the head bolts just stay with the 7/16 x 18 with Helicoils as you have already stated that perfect authenticity is not the goal but using the machine is.
I would have suggested scrapping the bolts and refitting with studs and nuts to get the most reliable arrangement since currently the tapped holes are into castings that doesn't lend itself to frequent dismantling but I appreciate that unless you remove the engine each time for a head removal or a valve check then the stud route is not practical.
I see that the exhaust valve appears somewhat large. Normally for best gas flow the exhaust valve is sized at 85% of the inlet size and where this occurs elsewhere the opportunity to increase the inlet valve size (only) has netted advantages.
Is the piston OE because the bore is worn, as you say with a lip but it is too tight at the bottom. The piston is for the most part scrap as the ring land for the middle ring is crushed so a new oversized piston in a rebored cylinder will probably be required. I would shoot for 5thou per inch of bore for the ring gap for an air-cooled engine and 1.5thou per inch for the piston clearance as they are prone to large fluctuations in temperature
@@clivewilliams3661 Someone good advice there. I'm definitely going to leave the head bolt size as 7/16 x18 as the threads cleaned up really nicely, although I'd have preferred a finer thread. Re the rocker cover bolt threads, I'll see what threads can be reused , and find a solution for the others.
It's a shame it's such a mess, but all can be made good one way or another 🙂
No. Just clean it up and replace the rings if they're damaged. It's not gonna be doing thousands of miles at high revs.
Found that really interesting and informative. Lovely bike. I have a '59 C15 which is not so impressive but I love it despite its extensive oil leaks! Al the best sorting out after that butchering. Some people should not be allowed to touch a bike engine.
Thanks, glad you enjoyed it. Yes, it'll take some sorting, but hey ho, if we're going to buy and ride motorcycles from decades ago, we have to expect these things I guess. 😊
Nice video Thanks a lot 👍👍
Glad you enjoyed it
i reckon the bloke who built that must have touched my B33 !!
Oh dear... 😁
Hi Adrian, from one ex racing shed dweller to another, as troublesome as these are, these are the things that keep us sane. Would you consider just re-helicoiling every available thread you get to over to metric, just purely on the better availability of bolt materials, threads and sizes. I've done this before on rebuilds and paint marked each of the bolt groups ie R/cover, head, barrel, side casings, as I went and added to it on each subsequent strip down until all the bolts are metric. Unless I was wanting an original rebuild it works out easier in the long run.
I'm not mad on the idea of moving to metric. I'll assess everything carefully and work out the best solution - best as in effective and not too expensive. As you would know from racing - what works is what you do! 😁
the bore condation you cant say happen when it seized up.. iam sure some did. but with what you said about the bolts. iam wondering what bore issues were there before hand. sad when folks damage motors puttin them togther ...
Whoever assembled it didn't seem to know much at all :-(
When I began riding in the 60s there were many more experts available, sadly time has removed them. When I took a badly butchered B33 engine to our local BSA doctor, for advice, he knew who had worked on it, and his comment was "That bastard should have his tools confiscated and be issued with a cast iron side valve".
Your BSA doctor is spot on! 😂
Hi folks, way off topic but in my much younger days I used to dream of owning an Airel Leader. Liked fairings even then! Seem to remember that one reviewer rode one from Scotland to London in the rain and claimed not to have got wet.
Nice bikes, but I don't believe the bodywork protected the rider from rain that much! 😁
Looking at valves & plug the mixture looks fine I was always told and found with experiance that a Rich Tea biscuit colour was what you want.
It's about right, but with the experience I've had, I'll try a bigger main jet and see if that's better or worse.
@@t20racerman All depends on how long you actually run on the main jet. irc a freind back in the late 70s with a B25 starfire said in was runnining the best it ever did moments before the piston smeared itself around the barrel.
@@kevinwilliams4899 On my racing 2-strokes, if ever they ran superbly flat out, you'd worry - and re-jet after the race if it survived. Had to have a barometer in the tool kit because if the air pressure dropped, you'd seize up unless you re-jetted. Crazy times!
@@t20racerman
If only they had had EFI and MAP sensors then.....
Modern fuels are more difficult to read the plugs by !!
I presume that's a pattern piston possibly from Australia. I used one made in Italy on my ajs. The ozy ones are prone to seize up as there made out of the wrong alloy.
Not sure where its from, but now I've measured accurately the clearance between it and the cylinder, its was always going to seize when hot 🙁
Hello there, this might be obvious but with all that bodgery in the top end I would be worried about the rest of the motor. I used to have a bike salvage yard here in the States and the things I have seen, especially to old British Bikes, still give me nightmares.
I'm putting off stripping the bottom end for that very reason... What lurks in there? 😬 A job for the winter methinks
Probably made the cylinder/piston job with the same clearence as a modern liquid cooled engine. Nice bike!
I guess so - but tapered too! 😱
@@t20racerman True...bad work or tools...or both!
Aren't Previous Owners great? And they leave such treasures for us!
They certainly do
I know the full and correct name is "carburetor" but we only ever call them a 'carb' in Australia. Nice bike.
We mostly say 'carbs' here too 😁
Hi Adrian , from Québec.
Looks like you'll need new threads , new bolts , everywhere. With sizes 1/4 , 5/16 , 3/8 ,
I'd have no idea where to go up in size , then find the proper bolts ! As to heli-coils , I find those on the market a bit short of threads. Hmmmm...
I say that not knowing exactly what sizes your bolts are , of course . I've done my Kawa's 16 M6 cam bolts going to longer 1/4-20 ones no problem , just using a 13/64 drill then the hand operated tap --just beeing very careful.
Hi there. Yup, work to do. Not a huge fan of helicoils, although they are fine in some situations. Still working on a strategy...
English bikes are lovelly.
I had a 1932 Favor, with a Jap 250cc engine.
Interesting fins on the admission pipe, I've never seen this.
I miss my XT500 :)
The mix of metric and imperial makes no sense.
There are fine thread metric, 1.0.
Sounds nice. JAP made some great engines 😊
@@t20racerman I loved it :)
Makes a good boat anchor.
A bit harsh!!!
A friend of mine had a Triumph T90 which had been rebored n new pistons but it too kept seizing and the only cure was to run it on Duckhams Q 20/50 no more seizures !
Obviously a bit tight too then. 😊
That was very interesting so you got me curious meaning another sub 👍
Thank you! More to follow soon
Hi Folks, I'm a silver haired ex Norton owner. I've stripped one of those and rebuilt it but am not Aerial novice, let alone an expert. However .....6:35. That's a BIG air leak. 11:00 Normally a corse thread is used into cast iron, a fine thread is more suitable in aluminium. I think this has been bodged.
Yup, quite a big air leak! The threads on these should be:
3/8 x 26 for the head bolts and
5/16 x 26 for the rocker cover bolts
MY head ones are 7/16 x 18 BSF which is quite a difference.
Did it have the gudgeon clips in? Looks to me like the gudgeon pin has made that big scoring, as it stops about an inche below the top
No, they were in place. I've had the bore honed to the correct size and it cleaned up a treat. 😊
A Layman's take (and I'm not even going to put thought into this, so as casual as can be).. Considering how difficult finding B.S.C. replacements must be by now, especially good condition and hearing you mention making the bolts, how unpopular would you be switching to M8 ..and might you mitigate this at all by re-cutting modern bolts (socket head or otherwise)?
I'll probably have a couple of M8s where the damaged rocker cover bolt threads were. Will look at putting in time-sert inserts. The head bolt threads in the cylinder have already been opened up to a bigger size, and I can't change them now. They cleaned up ok, so I'll use them - but with decent bolts to hold the head down
What brand of two strokes did you race, did you have British, European or Japanese bikes.
Look at my other videos and you'll see my 1967 Suzuki T20, and my 1980 TZ350
😁
Thought is that some old oil seeped into the bolt holes, and is acting like “old style loctite.”
Maybe. The oil certainly used to seep out!
Tight gapa there I run 9 thou on rings min and 3 thou piston to barrel on my BSA 441 and still get 150+ psi in compression had even 185psi once
Ariel recommend 5-7 thou on these! It was clearly too tight with that big cast iron barrel. I had a 441 once - nice bikes :-)
@@t20racerman That sounds right dis similar heating considered, had a 500 International with cast barrel. I have used the daily runner 441 36 years or so many barrels LOL! Wish they were more like my 72 R60/5 swb barrel wise.
6:10 Why would air leak in there? It's above the throttle slide and not subject to the intake depression.
The pressure in the carb is lower than outside, so it definitely would draw air in through there. Not a lot, maybe, but it was a consideration 😊
Very nice bike, terrible news from the engine. I wonder how that all came about?
Assembled by a mechanically illiterate gorilla perhaps? 😢
That broken head is due to blind hole hydraulicing. There has been oil in the blind hole and someone has tightened a bolt down on it causing it to explode.
That definitely sounds like a possibility.
The previous owner sold me his toolkit. It was a bowsaw, vise-grips and a heavy rock. In fairness, he didn't charge me for the bowsaw because "it doesn't work properly" but it was fine when I switched the blade right way up!!!
😁
after finding what had been done to the engine I'd want to strip the whole bike specially the hubs and brakes to make sure the rest isn't a death trap
Already done the brakes, wheels, clutch etc. Just the bottom end left to worry about. I'll strip that in the winter
@@retiredbore378 The brakes are certainly 'interesting' 😁
I would say plug is wrong grade for 'high speed' use, probably have a 'soft' plug fitted for trials use?
Correct grade will show a definite 'line' on the ground strap (not a lot of people seem to know that)
Otherwise, colour doesn't seem too bad with unleaded fuel. Does it have alcohol in it? (in USA E-10 is norm, instead of feeding animals or humans, they turn corn into ethanol)
I was thinking screw missing from carb top wouldn't have much effect until I saw you had a Monobloc on there.
Never been a fan of them or Concentric's
Apart from separate float chamber having some 'issues' on sidecars when cornering, the older type was a much better carb in my opinion.
You could use a smaller size and get same or better airflow ( the Japanese versions eventually got developed into Mikuni 'smoothbore' classed as a 'racing' carb)
Is that an A7 or A10 in background?
I've got a '52 A10 plunger with 'sidecar' primary (duplex chain)
I was expecting wrong bolts fitted when you said previous owner had done 'cosmetics'.
Probably only ever seen metric bolts and never heard of Whitworth, BSF, BSC, Cycle, B.A. etc. (don't remember if Ariel use their own threads like Triumph?)
Tight threads - common problem.
Probably fitted UNF 60 degree thread instead of correct BSF 55 degree thread angle?
I would tap cylinder for a standard size bolt (probably 1/2" or even a metric?), make some inserts and go back to original bolts (one thing I've always hated is mix and match , metric on metric bikes, inches on British bikes)
Those 'lines' in cylinder are from gudgeon pin, seen it before (worst was a Jubilee Bonneville when I worked at Honda/Triumph dealers, Meridan forgot cir-clips and wore a slot between cylinders)
Some very interesting comments there, thank you. A colder plug is certainly something to consider, although when I've checked it other days (albeit not a proper plug-chop) it's looked spot on. I'll definitely go up a main jet.
Having UNF head bolts in BSF threads sounds plausible as I found the barrel threads cleaned out lovely with a BSF tap, but a die on the Allen bolts (just to see) was very tight, despite being the correct size.
Yup, it's an A10 - a pretty special one. Check out my BSA playlist to see more. I'm also relaunching this channel, so more BSA vids (along with other stuff) coming soon. 😊
That plug doesn’t look all that bad to me. Maybe a touch lean given the very light tan color, but it wasn’t bleached out white which one sees on a plug that is obviously the wrong heat range or in a very lean running engine. I might try to get a plug one heat range colder, but otherwise I wouldn’t worry much based on that plug alone. I am writing this only a few minutes into your video so I am curious to see what comes next.
I'll go up one on the main jet as its a tad weak there. It's fine through the rest of of the rev/throttle settings though. 😊
Does anyone still reproduce parts for these old bikes?
Yes, Draganfly Motorcycles in Bungay. Massive range of parts. 😊
Well done you. Just a thought, as I ran into something similar many, many years ago, is the piston in the right way round ? Good luck and I truly hope you manage to helicoil everything tickety boo.
Thank you. The bore was VERY tapered (it's been measured now) and will hone out. As for the rest... 😱😭😭😭
Great video lots of love your worst Physics student ever. 😂
Hi Louis. Nice to hear from you - and you certainly weren't the worst! :-)
I like the quality of this video. Sounds like this bike went through some dodgy owners. Be prepared for more mischief. I've been through it enough now that I ask more about the owner than the bike when purchasing.
Thank you 😊. Yup, some dodgy work on this bike over the years. They weren't valued as classics though back then, just an 'old bike' that needed fixing (somehow!) to get hit going again. Bound to be the odd dodgy repair over it's 74 year life 🙁
Motorcycle mechanic by trade and 2 bobs worth. I've seen many overtight rebores from engine reconditioners. I've seen many loose clearance engines running perfectly well. Just scrape any aluminium that's adhered to the bore and hone. Replace the rings. Clean up the piston if it's OK. Air cooled engines get hot, really hot. They need clearance.
It was way too tight - and tapered too! No wonder it nipped up 🙄
It is hard to believe some of the butchers who do vintage resto's. One chap admitted to me that he did not even put new bearings into the bikes he was restoring because none of his customers ride them very much.
Oh my gosh... :-(
Beautiful bike. Hope you get it all sorted out. One suggestion. Try time serts rather than helicoils. I absolutely despise helicoils.
Agreed - but 5/16 x 26 BSC timeserts not available
@@t20racerman ok, didnt know that. I assume you are trying to keep the bolt sized stock? Even though the bike is kinda not ? Personally I would just change to metric. Specially as most would never know. But either way, hope you success.
I can't believe someone just decided to stuff the wrong sized threads in! Who owns an old machine and doesn't bother to figure out what the correct thread is?
Awful isn't it? 🙁
With that level of bodgery it's a wonder you had it running, I would be very nervous of everything else on the bike now.
It took some work to get it going I must admit. It's run beautifully since though (apart from seizing!), so I'll build the top end back up, use the it through the summer and have a look at the rest in the winter. But yes, no big sense of confidence in the rest of it! 😬
Ok, towards the end. Hmm, I think I would go with helicoil inserts. Those head bolts are a critical component and need to be of the correct material and quality. All bolts are not created equal! Just make sure there is enough 'meat' around the inserts. Liked and subd.
I don't think helicoils will be strong enough for the head bolts - but fine for the rocker cover bolts.
The cylinder threads cleaned up nicely - they've been taken up to 7/16 x 18 BSF by a previous owner, and although 18tpi is a little too course for head bolts, I'll use what's there if it works
If they go leam mixture for any reason extra heat And less lubrication go together.
I'm definitely going up a size on the main jet. It was fine for the rest of of the range.
The piston clearance was the main issue though - a tapered bore and far too tight!
Oh dear, a real mess. I hope you went round and put Helicoils in all the threads. Sounds like some klutz really had a field day with it!🤔 Also, be aware that fitting a spacer on the carb means your mixtures will be different from the specs. P.S. Is that a Rocket Gold Star behind the Ariel?
I'm still working on the best solution for the threads. I love Time-serts as they are SO good, but cycle threads not availiable, whereas helicoils do come in the correct thread sizes
The BSA is a heavily modified A10. I'm releasing a video of it this afternoon - thrashing it around the countryside! More to come. Also, do check out my channel playlists as there are a few of my BSA..
Looks lean to me. The plug earth side is light all the way back to the thread and the centre is a bit 'pinky'. Black around the thread, dark colour on the earth and a tan or darker brown on the electrode would be much happier. From the general combustion chamber carbon it absolutely isn't rich for sure.
That's what I think. I'd checked the plug a few times before and it was spot on - but those times it was not a proper fast, main jet test, plug chop. It was clearly weaker on the main jet than through the rest of the rev range. I'll go up a size