The grin on your face Mustie when it fired up and ran properly for the first time was priceless. Like a kid in a candy store. Never grows old. You keep it real.
Umm, nahh, gas , spark check piston , then you have all sorted out , and check the carb . Most 15 year olds in europe knows this and can fix it without any problems.
Yep, nothing is worse than when a guy bring in his machine and a box of parts he'd removed after watching a couple of TH-cam videos. Unlless you happen to know that year, model and make really well, you're in for a heck of an afternoon if he's lost a spring, bracket, or gasket or two along the way.
dude this is the most comprehensive repair of a scooter i’ve seen! you really help a novice like me to understand what you’re doing and looking for. thanks a lot ❤
I feel decently confident in my repair skills and I must say I'm impressed. I would also have started with the carburetor but after that I'd be heading straight to a compression/piston ring scenario (based on the smoke) and after that a valve adjustment. I learnt alot during this video.
Just realized I’ve been watching you for about 6 years if not more I’m now 19 was about 14 or 15 when I first found your channel I WOULD LIKE TO THANK YOU I NEVER HAD ANYBODY TO HELP ME LEARN ALL THIS STUFF AND YOU HELPED ME A LOT WITH YOUR VIDEOS I AM NOW A SERTIFIED MACHANIC IN MICHIGAN
One very important lesson i learnt from my engineering days when diagnosing problems is that if the job has been worked on by somebody else to always and I mean always double check their work because most often than not you will find the person before you has done something wrong which is why the thing being worked on is still faulty. Many many times I have come to a job where the person before me has installed something wrong and 98% of the time it relates to wiring. Very very good video.
Love this.. Im not a very Mechanically inclined guy however i just picked up a china 150 so I figured id start watching some videos like this just to learn a little bit.. whats what, kind of learn my way around a small engine and such.. I have learned a lot from just this one video and would just like to say that I really appreciate the time you take to do this because you have been VERY thorough and as you are working your telling us exactly WHAT your doing..exactly WHY your doing it AND explaining the sort of troubleshooting that specific thing is and what we would want to look for both on the good and bad end of the spectrum. You know your way around an engine and I am here to learn! Thanks Teach!
1:08:44 It's moments like this that we work on cars/bikes/engines. That is one happy man right there. I've said it before but I'll say it again. Your patience and problem solving process when faced with an unusual issue is admirable.
Mustie, I have been following and watching you for years. You are an incredible mechanic. You never cease to amaze me. 2 wires on this but damn what a lesson on these little bikes. Thanks for years of great videos
Benelli were quality motorcycles from Italy, founded somewhere between 1911-1921. They didn't fare as well over the years as Ducati or MV Agusta, unfortunately. This was one of the scooters produced in China after Benelli was acquired in 2005 by Qianjang or whatever they are called. Have fun finding parts! Thanks for all your videos, been great hanging out in the garage with you.
man, that takes me back. you're the first person to call channel lock pliers, water pump pliers that i've heard since my grampa died in '05. he always called them that, and he had just about every size of them there was, from tiny ones that might have been 1/2" fully open, to a pair that had handles that were over 2' long, and would grip a 3" pipe with ease. he even had a pair that had "parrot beak" jaws that were specifically for gripping pipes. i still have most of them, my cousin got the rest. you know, benelli sounds italian, but i'll bet the closest this thing ever got to italy was the pizza joint that i'm sure the previous owner rode past, since every town has at least one pizza joint somewhere. the benelli company i'm familiar with makes really good shotguns. scooters, not so much. well, no matter what, the price was right. it's hard to find fault with a deal where the machine was free.
@@georgebamber6871 imagine that. with the way this runs, they should prolly stick to making guns, those work. this...well, the last guy threw it away. i think that kinda says it all, doesn't it.
Benelli was a reputable Italian motorcycle manufacturer but i think thr name brand was purchased by china, just as AJS ( British bike manufacturer) was so often all that remains is the name not the original quality.
You'll have to move somewhere rich people live? I love watching these videos, but the real magic is what people are actually throwing away. Anywhere else it would be on Ebay?
I live 65 miles north of Alpharetta/Dunwoody. Those yuppies throw out so many impulse toys or sell them for 1/4 price with almost no use. You buy used up here in Hooterville, the stuff is used to death. Everything used is like buying from Mr Haney.
Looked like a rerun from a year or so ago. The switched wires and getting stuck in the woods was very familiar to a previous episode. Contents however is always good and never gets old.
I had a scooter a few years ago I got brand new as a Christmas present. Super happy and excited but anyway. Down the line of it being serviced by the dealer he took the sides off and put a screw through the main ignition wire so every time it rained the bike tried cut out 😂 took a bit to find the issue. But stumbled across it when checking luckily I wanted share my story to help others look for things like this. Even from a main dealer as well (from the UK sharing my love to you Mustie)
For anyone interested it is a sinnis shuttle 125CC 4 stroke. Good bike but has issues with throttle cable snapping once a year. Another fun story of a day 8am coming back from work after it iced over and my cable got jammed on full throttle and I had use the kill switch to make it 2-3 miles home 😂
This was a fantastic video. I loved the way you went through it methodically. I never would have got to the crossed wires! Makes me smile because it was only by watching your videos that I became confident enough to work on my sons bikes, and then my mowers and even my cars. I am jealous of the way you so confidently open up carbs and disassemble and reassemble them!
Get that carb slide in backwards on an _otherwise good_ machine, and you can be headed for a crash at full throttle. Actually *beyond full throttle!* :/
@@YodaWhat thats how i blew up my mx175. So sad. My fuel valve wouldn't close and the kill switch wasn't working. I was young and didn't know what to do.
Hey, Mustie, you got the Choke operation backwards. When you put power to the choke coil, it extendes-goes outwards 2-4 mm to close the "extra" fuel hole in the carb. When extended it closes the hole that gives extra fuel. Takes about 2-3 minutes to extend all the way. Measure it with a caliper before (when its cold) and after 3-4 minutes.
That's interesting;never saw an automatic choke on a 2 weeler.....The older yamaha's had a similar system; not a real choke,but a separate circuit in the bowl just for the choke,and was controlled by a cable,that connected to a small plunger with a rubber tip in the carb.
YES! I had a Yamati just like this and I believe the enricher was the issue with mine. The fix I would use when I hadn't run it in a while was to drain the carb bowl, then use the kickstarter to pull/release vacuum to the fuel valve to allow fresh fuel in, and then when it started, lean the scooter down on the left hand side and roll the throttle back and for for a bit. It would sputter for several seconds and then would run fine. If I didn't do that and started riding it right away after starting it, the throttle would bog down and it'd die like it was starving for fuel. But once it was warmed up and running I could stop it and start it up again with no issues. If I let it sit for a week without being run, I'd have to go through the same starting/leaning steps again.
This is such a coincidence for me! I just bought a Chinese made scooter for $70 and went through this process! The first thing I did was empty half a gallon of water out of the gas tank… lol. I’m fighting the oil injection and a charging issue right now. There’s a vacuum gas shutoff that I had to replace also. Love watching you bring things back to life.
The scooter repair man I go to said he routinely deletes/bypasses the oil injectors and just run with premix so as to eliminate the chance of fatal injector failure. As a rule by the time you realize that the injector has failed its too late.
I don't know much about those oil injection systems, but I have heard if you do a delete, you can cause them to run too lean. Good luck with the project. sounds like a fun one :)
Damn the wonderful look on your face when you fixed the reverse wires, was so awesome, I felt like I was right there with you, so freaking glad for ya, thank you for sharing this with us all.
The thin pipe on the exhaust is one of the restrictor's. To derestrict it, you cut the pipe off and weld the exhaust up.The Naraku CDI will be a replacement and a derestricted CDI
I bet the previous owner added the new magneto with the aftermarket cdi, upon reassembly he got the wires backwards and it never ran right, till you got it and diagnosed it correctly, nice job, I always learn something watching you mechanic!👍🇺🇸
1:08:30 you can't help but laugh and smile when mustie finally gets the throttle issue fixed and it revs up along side him. Man this was a roller coaster video one of your better ones in awhile!
I know this scooter! In Italy was called Benelli 49x It had two versions, first one like this offroad and an onroad with road tyres. Super rare, I think prodution stopped in 2011 according to some italian bike sites. There are some for sale in Italy if you want I remember it because I liked it when I was in highschool
When it's no start, it's always some stupid screw-up by the previous owner... or the engine blew up by being abused. I literally just came from work and the supervisors were working on a no signal from the motor. I was thinking, I guarantee it's a bad wire. Two hours later we opened up the plate to find the motherboard had a cable mashed up by their shop. Two bad pins on a flex cable.
Once again Mustie1 you prove yourself “da man” that no quit attitude is the key, I seriously appreciate the tips and share of knowledge you show and provide. I have applied it in several of my own projects and it has helped a ton! Thank you Mustie1!! More please love it all.
Mustie is the pure joy of being able to pursue a passion. Not always full of nothing but fun, but the end result is always worth it. His reaction when he solves an issue is gold.
Just found your channel and LOVE that it is a long video covering the entire fix and diagnosis. This is a SUCCESSFUL fix for sure. It didn't run and could be used now by someone.
hey mustie the expansion chamber before the muffler is part of the intake in a 2 stroke. venturi effect and pressure differentials caused by the expansion chamber increase the exhaust scavenging which in turn controls the intake charge....exhaust leak before the expansion chamber will affect how much exhaust is pulled from the cylinder which in turn affects how much air fuel mix gets drawn into crankcase. i dont know that that is the only issue happening here but it can explain the idle/accelerate issue. thanks for the videos
its uh, not a venturi effect, its pressure waves. the pressure puls from the engine reflecting off the back of the chamber and cramming wasted unburnt fuel back into the cylinder before the exhaust port is closed during a certain band of the rpm range. but close enough.
@@EllaBananas whenever you have a restriction followed by an enlarged closed space...you will have a decrease of pressure and an increase of velocity ..excuse me for labeling it a venturi effect while it is almost identical and is irrelevant as i know how it works and you know how it works and mustie knows how it works
You need to de-restrict that little bad boy and take out the restricters in the exhaust and go up a jet size or two. You should easy get 50 MPH out if it and get some more speed if it’s just for fun. Looks a little rich on the oil too. Thanks for sharing with us by the way as the video proceeded I would of done exactly everything you done to try and solve its irregular running and was as confused as you were but points for coming across that wire in the end and well spotted !
Great teaching video! And great example of how someone that tries to repair a problem without a strategy can cause more problems that they started with! Excellent work, and congrats! Your smile and laugh of victory made my day!!!!
I think we were all pretty perplexed trying to figure this one out. It's usually challenging to go where others have been before! Excellent troubleshooting Mustie1! Take care and thanks for posting!
I was on the phone with tech support once and the guy told me that if someone worked on it before me and it didn't get fixed I should always check his work. When you think about it, it's actually not a bad idea. 🤔 I only just found this channel but I love it. I appreciate you Mustie1. Thank you for sharing your skills knowledge and experience
This guy is a genius. I didn’t understand a lot of what he was doing but the video was so interesting I had to watch to the end just to see if would solve the problem. He has a lot of patience, i would’ve taken a sledgehammer to that thing.
I had a problem with an overflowing carb of similar design on a motorbike. After checking the float, making numerous adjustments to float height, and checking float valve and seat repeatedly, I finally found the issue. It was a crack in the brass overflow pipe. I discovered this by clamping the float bowl in a vise (using some wood to provide cushioning), filling the bowl with petrol, putting my finger over the end of the brass pipe, and blowing through the overflow tube - I could see bubbles coming out of the brass pipe about half-way up. I solved it by using Araldite to glue a slightly larger ID brass pipe over the original, which I didn't want to risk trying to remove. No leaks since, and I make sure to drain the bowl after use and turn the petrol off at the fuel tap.
Small motor gas line slipped over the brass overflow pipe also works to seal the crack. Crack comes from water in the bowl freezing and splitting the brass pipe.
The only true bit of the story about this scooter was that it had only done 500 miles ... Mustie - your combination of small-engine genius and absolute stick-at-it-ness is totally inspiring. These episodes you put together are like visiting with a mate in his workshop for a while for a mix of coffee and carbon monoxide. Intoxicating ... and have been since the beginning in your home garage. Thank you from the UK.
These scooters are the easiest things to get running. I bought one for $200 with no spark, pretty new it was a 2020 150cc with under 200 miles, bought a coil and CDI for less than $20 and it fired up and ran great!
Hi Mustie1, that exhaust is a expansion model, designed to increase counterpressure to the exhaust port. It's what the cool kids want, to make their scooters faster and flashier. Benelli is an Italian motorbike-builder. They used to produce, next tot mopeds, beautiful six-in-line motorbikes.
The bolt on the exhaust is a sheetr-off bolt. Usually used on ignition barrels on cars so when tightened up, the head snapt off and the barrel cannot be removed by thieves, unless they come prepared with a hammer and chisel.
Ive NEVER had more fun than I did riding a step-through moped through a forest trail. Its got no business being there but 15mph on one of those feels like 100mph on a dirt bike.
It was obvious that he had thoughts of not figuring this one out. I was probably almost as thrilled as he was when found the rev issue!! Also... I actually get motivated every week to get shit done because Mustie1 pushes through and doesn't make excuses. Well, at least none that we see :)
There's no way he wouldn't have figured it out, eventually. A scooter is way too simple of a machine for his knowledge, he would've taken it apart bit by bit until he found what's wrong.
around 40:00 when it starts it's a misfire situation and to me it sounds electric and that would push me into a rev limiter issue or electronics. Some mopeds do have a rev limiter.
By the way I did experience a similar behavior on a moped I once had with breaker points - the axle the point arm rotated on was corroded and made the arm move too slow. Decent idle, no rev and when revving it did sound the same.
I worked on scoots for about a decade. It was fun watching someone make overqualfied noob mistakes like i did. You should be going closer to 45 on that. They like to put restrictions in different places. Either a main jet that is too small. A washer that restricts the exhaust or a washer in the variator. We used to work those 50cc 2 strokes up like you wouldnt believe. One time i took off on a test ride on the most tuned one we ever did i almost lost it on take off. Im glad i was about 250lbs at the time to keep the wheel down
I learn so much watching this channel. Stuff I would never have had access to otherwise. It is extremely interesting to see how many different ways the engine designers come up with for the internal combustion engine.
I was convinced from the start of this video that the ignition timing was at fault. I suppose I was wrong, but it was an ignition fault at least. Great work and well done.
That is pretty darn cool! I'm surprised that just a crossed wire would do that. Live and learn. Cliffhanger this was!! Thanks for the great content, as always.
I firstfound you doing the red Karman Gia, and followed most of your projects since. Yourknowledge is amazing, be it new or old junkers. Great job every time sir.
This was a good one! Challenging, but you can't stump Mustie1! LETS GO! You had me clapping the moment those RPMs came up and that back tire started spinning 😄 had a huge smile on my face. The sense of accomplishment is such a great feeling. As an Automotive Technician I can relate to that feeling of figuring out a problem that at first has you stumped. Love it! Keep the "will it run" videos coming sir!
It looked to me like the float level was too high, and lowering the float level should have a similar effect as lowering the float needle, which helped, but not enough. The excess oil also seemed awfully persistent to be just in the crankcase, which makes me think the oil pump may be out of adjustment or defectively pumping too much oil.
1. Drain tank of all fuel, and make sure only oil enter carb by way of oil tank. 2. Check for any restrictions in exhaust system. 3. 3. Check cylinder for carbon deposit boil-up nr=ear exhaust port. 4. Remove variation and check to see if all roller weights are rolling properly. 5. I have yet to see rear wheel spin up under acceleration. Make sure there are no restrictions to rolling of rear wheel under throttle opening.
The engine might be running rich because of the exhaust constriction or the Bistarter. If you take that half moon shaped exhaust restriction off the cylinder, that's what makes this a "Moped" rated scooter in many states legally. The bistarter is the plunger you were calling a solenoid, it's not. Hook it up to 12 volts for a few minutes, check for length, should get longer after 5 minutes Should be able to run close to 30~35 mph with that plate exhaust port removed. Also check the engine pulley on the CVT, they sometimes put a metal ring in that prevents the CVT flyweights from running the entire length of their operation "ramps" also restricting the top speed to about 20~25mph.
Yes it can constrict the flow of exhaust, but the purpose of the "half moon exhaust" is because its called an expansion chamber and is required in 2 stroke engines to help with scavenging to use backpressure to push unburnt fuel back into the engine
Listen I've worked at a Genuine and SYM dealer, and you don't leave the little port restriction in if you want the full affect of the expansion chamber's pressure waves to work. I've owned enough 2 stroke bikes to know this.
@@tauncfester3022 My bad dude, I misunderstood what you wrote. Yea that makes complete sense if you remove the port restriction, its only there by law anyways to reduce the power output
Nice edited video. I enjoy the longer videos where you show every step but this one you definitely edited but still has the longer run time. Nice and cleanly done. I thought it was the choke the whole time, with the loss of throttle control.
If you take a hollow ground flat tip screwdriver (or regrind a round shank screwdriver) so the tip looks like )( viewed from the side it will grip carb jets rather than smear the slots. My Vincent-restorer mentor invented that trick in the 1960s when most jets were slotted and it works a treat if you do a tidy job of grinding. Those Clore JNC 660 jump packs are outstanding and Clore sell replacement parts. They're easy to work on too. I bought my first in 2014 and replaced the batteries last year. I bought a second mostly in case something happens to the company.
I love watching your videos, how you explain things and actually show your wins and fails. I have learned so much from you, even though my Biking days and fixing cars are well over, Just watching you fixing up stuff is very theraputic. + you get some great freebies- so you win, and we your audince win!
Oh man, I had Benelli scooter about 8-10 years ago. They are actually pretty decent scooters, at least mine was back then. Absolutely loved it as a quick commuter to the shops in Brooklyn.
Over to quickly and with the exception of one video.. are all on TH-cam, there has to be a easy way to upload to both Rumble and TH-cam.. I guess that's a good problem to have though.
Damn dude! That was an amazing effort and success! Great job! Always astounded at your skill and dedication to not being bested by other folks cast offs. Thank you for the great entertainment!
Good on you for getting it running again, its quite a feeling! However, when you finally figured out the reason, I cant help to get unreasonably angry, when "pre-owners" mess about with electronics, and screwing up because of their incompetence. Yeah....been there, done that.
Sounds like the CVT has a limiter- spacer on it to limit ratio change. Lots of markets got these because of local market regulations. There should be info online on how to get rid of this limiter hardware. Maybe you can get a tuning kit for this thing? Malossi? bigger carb. + jetting? exhaust seems OK. These things can easily be made to run 50mph
Often disconnecting 1 wire is all you need to do. I know that on my Yamaha mint 25KMH version is limited to 35KMh it is the blue wire of the CDI I only use 1/5 of my gas handle but the 45 versions (limited 50) they use more travel. but they do sound like this on limiting by missing fire moments to limit speed/ engine ref.
@@Montimoped It depends, some can be fooled with 1 wire. not all though. As M]my Mint only needs 1 wire to be disconnected but Might be different in this one.
Great video as always. a little FYI...the black cdi boxes come with around 5000 rpm rev limiter built in,,,that's why people change them out. Try the red cdi box.
Good catch on the wiring. Did you ever check to see if it actually had 2 stroke oil in the tank ? I've seen everything from motor oil to gear oil put in 2 stroke tanks.
Congratulations Mustie1...your knowledge kicked in and fixed the unfixable! I honestly believe you could fix a bad day!!! THANKS for all you do! I like it that you put the camera EXACTLY where we can see exactly what we need to see, plus, you treat the camera like a person...you ask our opinion, sometimes, and I catch myself verbally answering you. It's THAT personable! You explain everything and how stuff works, and theory stuff, and...well, nobody else has anything like you do or as good of content as you do. You don't adlib, nor have nauseous music playing in the background. You speed up the feed thru repetitive time consuming procedures. It's still there, where we can still SEE how you did...whatever, it just shortens the time it would take for a fullness of video. Your editing is superb and all of it is VERY MUCH APPRECIATED !!!
That engine is a horizontal minarelli. Found in tons of scooters. It was the motor in most 2 stroke yamaha scooters as well. Pretty much the same motor as a bws50 yamaha.
Its a clone Minarelli Horizontal air cooled.. In the 90er they used the original one. Some parts of the original minarelli will also fit on this clone engine.. The cilinder looks to be the same. (only the clone using P12 piston barrel.. And the old using P10.
Yup.I have a 2 stroke Yamaha BWS been sitting in my garage for about 10 years, it has that engine. It was running when I parked it, I'll get around to starting it up and selling it sometime.
Hey mustie, long time admirer here... I think the science community could use your skills with their problems with FUSION. You could probably have a FUSION REACTOR firing in a video or two! Awesome display of diagnostics! Thanks so much and this was fun.."kick my ass"....No way!
You are 1 of the smartest people i know on TH-cam when it comes to fixing stuff and or figuring out stuff i think its amazing what you do i myself was a handy man back in the 80s and 90s if i couldn't fix it it wasn't worth fixing i love watching your videos always will great work always ✌🇺🇸
Question everything about what previous 'mechanics' have done when you step into a partially disassembled machine. Good work, good info, good entertainment.
Mustie is a legend! I wish I had his talent! Love every video he does - especially the ‘will it run’ ones…. Well done for fixing this. Don’t think I could’ve fixed it - keep the videos coming 👍👍👍
I have his talent but still love watching him tackle his challenges, it reminds me so much of me … but hey anyone can learn this, just find some junk/treasures to restore … practice can make you as good as Mustie …. Also pay attention to the details in his videos and you will do well …
I would try decoking the exhaust with a caustic soda solution. My old MZ 2-stroke used to refuse to rev when the silencer needed a decoke, easy to do and doesn't cost much.
@@RIMHQ-YT Remove exhaust from bike. Block one end of the exhaust with a potato. Make up a strong solution of caustic soda and pour into the exhaust until full. Leave overnight, then remove potato and drain. You may need to repeat a couple of times. Keep the caustic away from aluminium as it attacks it.
I bought a 150 for my daughter with 14 miles. The dealer couldn't get it to run so they sold it for $600.00. The only adjustment was the idle. So I got a slightly larger carb with interchangeable orifice seats. With the larger carb and a 4x larger jet orifice, it can run 60+mph with me and my wife on it. Surprised me, I'm 6'3"/250lbs and she's 130lbs and it pulls off from a stop very well.
so basically the most common problems with scooters or simple motors in general are carburetors being messed up, maybe some gaskets(low compression problems) and electrical problems. If that is the case i learned a lot from this video. Thank you bro! 1.5h spent with quality first hand content.
No; The biggest problem with scooters/bikes is that at least 2 other people have messed with it before you get it...The original problem was the air cleaner not seating on the carb properly, and the people before messed with everything BUT what was originally wrong; Not putting it back together properly...
Often on 50cc scooters the 'variator' (the front pulley) has a spacer washer to prevent the front pulley halves coming too close together, and this limits the top speed of the bike. The 50cc bike I had went from a top speed of 30mph to 50mph just by removing this. Mine already had the exhaust restrictor removed as these aren't required in the UK. This might be worth 10mph as well.
I was thinking the same,plz remove the speed limiter! I hate that cos it revs the engine to the max and the bike is not moving. Totally agree that bike should reach 50mph no problem. And yes,many of those exhaust had a sound trap you could remove too and the engine will be happier. With some simple mods you could have a very fun bike to ride.
Yes, very likely as you can clearly see the outer perimeter of the variator pulley halves have never had the belt reach the top because there's still a shiny new finish where the lower portion has been dulled by belt contact. Pull that spacer from between the two halves to get full transmission range and a higher top speed. There may still be a restrictor inside the exhaust too.
I had a Yamati very similar with a similar start up issue and I believe my issue was the enricher. The fix was to use the kick starter until it started sputtering and then lay the scooter on its left side at about a 45 degree angle. I don't know if this moved the fuel mix around in a weird way but if I did this it would idle and run normally. I didn't have to do this every time I started it, just the initial time if it had been sitting up for a week or more. If I went to start it the next day, it would be fine. I think it also had a small leak in the oil injector shutoff that would allow more oil into the carb (gravity) when it was sitting up. Mine topped out at 45mph. I had another scooter that did that same break-up issue on full throttle and I chased what I thought was a carb issue and turns out it was a faulty spark plug.
The auto choke works as it warms up .When cold, it has the port open to allow more fuel to pass into the carb. When it warms up, the plunger is pushed out and the needle closes the port for the extra fuel. If you leave the scooter with the ignition on when it is cold, it will close the choke and it would be difficult to start. I found this out when mine didnt start after leaving the ignition switched on. Takes ages for it to cool down to be able to start it.
@@michaelhartzell9758 I would never have thought it was the wires on the CDI. The choke was working fine, but if ignition is left on, then it wont start unless the air is restricted. I done mine the otehr day and found I jammed the choke in the carb after stripping and cleaning hte carb. Blocked of fthe air at the carb and it started, I checked my choke and now it startes first press of the key.
Mine has the opposite problem. A cold start on a hot day, no problem, fires right up. On a cold day, I don't even bother with the electric start: I could drain the battery trying to start it. Instead I have to kick it over maybe 50 times before it fires. The choke doesn't run off the battery. It runs off one coil in the magneto, so once it starts the mag will close the choke and keep it closed as long as it's running. In other words, the engine doesn't like the extra fuel when trying to start it in the cold. The 50 kicks activates the mag and eventually warms and closes the choke. I'm thinking of sending battery power to it through a switch to warm it up before trying to cold start it. We'll see.....
Can there be any problems with the pick-up being too close? assuming there is still an air gap, of course A technique I've seen is to slide a piece of paper between the flywheel and pickup, jam them as close together as possible, and remove the paper
Man, your tinkering skills are on God level! I'm almost inspired to start tinkering on my 200cc Chinese scooter. I've written it once before years back, but it's pretty much been sitting for about a good five six years. Thanks for the great video, they're all inspirations.
Italian 50cc scooters have "restrictors", typically a restriction in the exhaust (if i remember correctly also that small pipe coming off the exhaust should be removed and the hole plugged) and a ring to limit the travel in the variable pulley attached to the crankshaft
Back in the day, that was true but the newer bikes from over here use "electronics" to govern RPM ... that little "Red Box" the previous owner installed (and fried by reverse wiring) is where it is accomplished now.
The auto choke has a wax thermostat. when cold the chokes on, power is applied when running, which melts the wax and closes the choke via a heating element.
![GY6 171cc / 172cc BIG BORE BUILDER ENGINE KIT [A++ PERFORMANCE]](http://i.ytimg.com/vi/6yABpnaqd1Q/mqdefault.jpg)
The grin on your face Mustie when it fired up and ran properly for the first time was priceless. Like a kid in a candy store. Never grows old. You keep it real.
His laugh at the success gets me laughing, too!
I came here to say this. Nothing as much fun as watching Mustie win!
He had the biggest smile on his face!
When Mustie laughs, we all smile!
@@williamgraham8809 I love it that he laughs when he probably wants to swear.😁
Fixing a broken motor is one thing, fixing what the last guy did, that takes real skill.
Umm, nahh, gas , spark check piston , then you have all sorted out , and check the carb . Most 15 year olds in europe knows this and can fix it without any problems.
Yep, nothing is worse than when a guy bring in his machine and a box of parts he'd removed after watching a couple of TH-cam videos. Unlless you happen to know that year, model and make really well, you're in for a heck of an afternoon if he's lost a spring, bracket, or gasket or two along the way.
@@DN-me8mt I'd rather think any 15 y.o. would swap two color wires thinking he knows it all and it takes a smart mechanic to figure it out.
@@DN-me8mt im 15 & i dont know my pud from my ace
@@DN-me8mt that still doesnt fix the issue of "what the previous guy did" Which is a huge problem EVERY single time
dude this is the most comprehensive repair of a scooter i’ve seen! you really help a novice like me to understand what you’re doing and looking for. thanks a lot ❤
I feel decently confident in my repair skills and I must say I'm impressed. I would also have started with the carburetor but after that I'd be heading straight to a compression/piston ring scenario (based on the smoke) and after that a valve adjustment. I learnt alot during this video.
Just realized I’ve been watching you for about 6 years if not more I’m now 19 was about 14 or 15 when I first found your channel I WOULD LIKE TO THANK YOU I NEVER HAD ANYBODY TO HELP ME LEARN ALL THIS STUFF AND YOU HELPED ME A LOT WITH YOUR VIDEOS I AM NOW A SERTIFIED MACHANIC IN MICHIGAN
A SERTIFIED MACHANIC? Or a certified mechanic?
@@manolisgledsodakis873 Both sound the same to me. He is a mechanic not an English teacher.
Good for you! I am just a hobbyist, but have learned and used a lot from Mustie1 too.
not a certified speller
Good for you! That's awesome!
Mustie, you have done it again. Best show on TH-cam. Cheers mate.
One very important lesson i learnt from my engineering days when diagnosing problems is that if the job has been worked on by somebody else to always and I mean always double check their work because most often than not you will find the person before you has done something wrong which is why the thing being worked on is still faulty. Many many times I have come to a job where the person before me has installed something wrong and 98% of the time it relates to wiring.
Very very good video.
Part of the joy of these videos is the joy on your face when it works. Brilliant!
Darren’s laugh of success = PRICELESS 😆
Haha, yes!
We had to wait till 1:08:33 but we got it ! 🤣🤣
I was literally going to comment and read exactly what I was going to say👍…yes sir
Mustie's real name is Darren?
Love this.. Im not a very Mechanically inclined guy however i just picked up a china 150 so I figured id start watching some videos like this just to learn a little bit.. whats what, kind of learn my way around a small engine and such.. I have learned a lot from just this one video and would just like to say that I really appreciate the time you take to do this because you have been VERY thorough and as you are working your telling us exactly WHAT your doing..exactly WHY your doing it AND explaining the sort of troubleshooting that specific thing is and what we would want to look for both on the good and bad end of the spectrum. You know your way around an engine and I am here to learn! Thanks Teach!
1:08:44 It's moments like this that we work on cars/bikes/engines. That is one happy man right there. I've said it before but I'll say it again. Your patience and problem solving process when faced with an unusual issue is admirable.
Yes sir ! Love it
Mustie, I have been following and watching you for years. You are an incredible mechanic. You never cease to amaze me. 2 wires on this but damn what a lesson on these little bikes. Thanks for years of great videos
what an great example of a proper, problem solving mechanic. subscribed
Benelli were quality motorcycles from Italy, founded somewhere between 1911-1921. They didn't fare as well over the years as Ducati or MV Agusta, unfortunately. This was one of the scooters produced in China after Benelli was acquired in 2005 by Qianjang or whatever they are called. Have fun finding parts! Thanks for all your videos, been great hanging out in the garage with you.
It's a Yamaha Jog clone engine. Parts are plentiful and tons of aftermarket go fast stuff too. No problem finding parts.
man, that takes me back. you're the first person to call channel lock pliers, water pump pliers that i've heard since my grampa died in '05. he always called them that, and he had just about every size of them there was, from tiny ones that might have been 1/2" fully open, to a pair that had handles that were over 2' long, and would grip a 3" pipe with ease. he even had a pair that had "parrot beak" jaws that were specifically for gripping pipes. i still have most of them, my cousin got the rest. you know, benelli sounds italian, but i'll bet the closest this thing ever got to italy was the pizza joint that i'm sure the previous owner rode past, since every town has at least one pizza joint somewhere. the benelli company i'm familiar with makes really good shotguns. scooters, not so much. well, no matter what, the price was right. it's hard to find fault with a deal where the machine was free.
In my area, kids on those *deliver* the pizzas !
Same company that makes guns
@@marcryvon must be nice. where i live, the only thing that gets delivered is the mail.
@@georgebamber6871 imagine that. with the way this runs, they should prolly stick to making guns, those work. this...well, the last guy threw it away. i think that kinda says it all, doesn't it.
Benelli was a reputable Italian motorcycle manufacturer but i think thr name brand was purchased by china, just as AJS ( British bike manufacturer) was so often all that remains is the name not the original quality.
I would have enough working out the faults on this thing but filming and explaining to this guy is a legend
Wow, you got it for free?! That’s one heck of a bargain. As usual, Great job, Mustie1. You ,truly are the best!
I'm hoping to find something like this on the side of the road that just needs a little air on a tire. Man can dream can't he.....😊
You'll have to move somewhere rich people live? I love watching these videos, but the real magic is what people are actually throwing away. Anywhere else it would be on Ebay?
im hopin to find a old mechanical type writer
man can dream ye?
I live 65 miles north of Alpharetta/Dunwoody. Those yuppies throw out so many impulse toys or sell them for 1/4 price with almost no use.
You buy used up here in Hooterville, the stuff is used to death. Everything used is like buying from Mr Haney.
where I live you can't get anything for free (even a broken things have price same as working one) 🙄
i found my 3rd wife like that
Looked like a rerun from a year or so ago. The switched wires and getting stuck in the woods was very familiar to a previous episode. Contents however is always good and never gets old.
I had a scooter a few years ago I got brand new as a Christmas present. Super happy and excited but anyway. Down the line of it being serviced by the dealer he took the sides off and put a screw through the main ignition wire so every time it rained the bike tried cut out 😂 took a bit to find the issue. But stumbled across it when checking luckily
I wanted share my story to help others look for things like this. Even from a main dealer as well (from the UK sharing my love to you Mustie)
For anyone interested it is a sinnis shuttle 125CC 4 stroke. Good bike but has issues with throttle cable snapping once a year. Another fun story of a day 8am coming back from work after it iced over and my cable got jammed on full throttle and I had use the kill switch to make it 2-3 miles home 😂
This was a fantastic video. I loved the way you went through it methodically. I never would have got to the crossed wires! Makes me smile because it was only by watching your videos that I became confident enough to work on my sons bikes, and then my mowers and even my cars. I am jealous of the way you so confidently open up carbs and disassemble and reassemble them!
Yea...I always have spare parts when I get done...
Get that carb slide in backwards on an _otherwise good_ machine, and you can be headed for a crash at full throttle. Actually *beyond full throttle!* :/
@@general5104 if it went back together without them, it wasn't required.
No guts no glory.
@@YodaWhat thats how i blew up my mx175. So sad. My fuel valve wouldn't close and the kill switch wasn't working. I was young and didn't know what to do.
I love seeing your thought processes while diagnosing this. I really want to try to fix up a few motor scooters in the future.
Hey, Mustie, you got the Choke operation backwards. When you put power to the choke coil, it extendes-goes outwards 2-4 mm to close the "extra" fuel hole in the carb. When extended it closes the hole that gives extra fuel. Takes about 2-3 minutes to extend all the way. Measure it with a caliper before (when its cold) and after 3-4 minutes.
It's of the 'melting wax' kind right? Like eg a peugeot 2 stroke
@@gags730- I was beginning to think this moped was a WHACKED motor! ;)
@@gags730 Context is all important. No "whacked" without your "wax"!
That's interesting;never saw an automatic choke on a 2 weeler.....The older yamaha's had a similar system; not a real choke,but a separate circuit in the bowl just for the choke,and was controlled by a cable,that connected to a small plunger with a rubber tip in the carb.
YES! I had a Yamati just like this and I believe the enricher was the issue with mine. The fix I would use when I hadn't run it in a while was to drain the carb bowl, then use the kickstarter to pull/release vacuum to the fuel valve to allow fresh fuel in, and then when it started, lean the scooter down on the left hand side and roll the throttle back and for for a bit. It would sputter for several seconds and then would run fine. If I didn't do that and started riding it right away after starting it, the throttle would bog down and it'd die like it was starving for fuel. But once it was warmed up and running I could stop it and start it up again with no issues. If I let it sit for a week without being run, I'd have to go through the same starting/leaning steps again.
This is such a coincidence for me! I just bought a Chinese made scooter for $70 and went through this process! The first thing I did was empty half a gallon of water out of the gas tank… lol. I’m fighting the oil injection and a charging issue right now. There’s a vacuum gas shutoff that I had to replace also. Love watching you bring things back to life.
The scooter repair man I go to said he routinely deletes/bypasses the oil injectors and just run with premix so as to eliminate the chance of fatal injector failure. As a rule by the time you realize that the injector has failed its too late.
The good thing is you got what you paid for
I don't know much about those oil injection systems, but I have heard if you do a delete, you can cause them to run too lean. Good luck with the project. sounds like a fun one :)
I have a couple of these 50cc Chinese scooters, but they're 4 stroke.
9:45 everyone and their dog knows what a 2 stroke is but the fact that you explained it anyways; subcribed
Damn the wonderful look on your face when you fixed the reverse wires, was so awesome, I felt like I was right there with you, so freaking glad for ya, thank you for sharing this with us all.
The thin pipe on the exhaust is one of the restrictor's. To derestrict it, you cut the pipe off and weld the exhaust up.The Naraku CDI will be a replacement and a derestricted CDI
Hey bro
@@iancameron198 Hi.
Genious! Absolute spot on! Congratulations bud, you nailed it!
GOOD IT SOUNDS GREAT ONE MORE WIN TO BRAG ABOUT
You can heat the exhaust while it's off and pull the restrictor out as I done it 5 years ago to mine
I bet the previous owner added the new magneto with the aftermarket cdi, upon reassembly he got the wires backwards and it never ran right, till you got it and diagnosed it correctly, nice job, I always learn something watching you mechanic!👍🇺🇸
1:08:30 you can't help but laugh and smile when mustie finally gets the throttle issue fixed and it revs up along side him. Man this was a roller coaster video one of your better ones in awhile!
I know this scooter!
In Italy was called Benelli 49x
It had two versions, first one like this offroad and an onroad with road tyres.
Super rare, I think prodution stopped in 2011 according to some italian bike sites.
There are some for sale in Italy if you want
I remember it because I liked it when I was in highschool
Take it easy mate and we will all look forward to when you are fit and well again best wishes
Mark (Worcester) UK
I was sure it was the auto-choke. Go figure - somebody switched the wires. Great job, great video. You are THE G.O.A.T. of engines.
When it's no start, it's always some stupid screw-up by the previous owner... or the engine blew up by being abused.
I literally just came from work and the supervisors were working on a no signal from the motor. I was thinking, I guarantee it's a bad wire. Two hours later we opened up the plate to find the motherboard had a cable mashed up by their shop. Two bad pins on a flex cable.
@@firesurfer They will start fine without choke.
@@ProctoLogic so ?
@@ProctoLogic Wrong
@@lordracula2461 Choke is always on until it gets power.
Once again Mustie1 you prove yourself “da man” that no quit attitude is the key, I seriously appreciate the tips and share of knowledge you show and provide. I have applied it in several of my own projects and it has helped a ton! Thank you Mustie1!! More please love it all.
You are so relaxed and never give up that scooter would have been flung into next week if I was trying to get it going well bloody done my man.
Can nothing break this man!?! Love the perseverance, love when the 'fix' is found, love this channel..."all hail Mustie!" 👍
Mustie is the pure joy of being able to pursue a passion. Not always full of nothing but fun, but the end result is always worth it. His reaction when he solves an issue is gold.
Just found your channel and LOVE that it is a long video covering the entire fix and diagnosis. This is a SUCCESSFUL fix for sure. It didn't run and could be used now by someone.
You’re a very intelligent man and I appreciate the content you make. Keep being you Darren!
hey mustie the expansion chamber before the muffler is part of the intake in a 2 stroke. venturi effect and pressure differentials caused by the expansion chamber increase the exhaust scavenging which in turn controls the intake charge....exhaust leak before the expansion chamber will affect how much exhaust is pulled from the cylinder which in turn affects how much air fuel mix gets drawn into crankcase. i dont know that that is the only issue happening here but it can explain the idle/accelerate issue. thanks for the videos
I bet he knows that already.
@@Hjerte_Verke probably but the little things can get you..murphy had a law i think.
its uh, not a venturi effect, its pressure waves. the pressure puls from the engine reflecting off the back of the chamber and cramming wasted unburnt fuel back into the cylinder before the exhaust port is closed during a certain band of the rpm range. but close enough.
@@EllaBananas whenever you have a restriction followed by an enlarged closed space...you will have a decrease of pressure and an increase of velocity ..excuse me for labeling it a venturi effect while it is almost identical and is irrelevant as i know how it works and you know how it works and mustie knows how it works
You need to de-restrict that little bad boy and take out the restricters in the exhaust and go up a jet size or two. You should easy get 50 MPH out if it and get some more speed if it’s just for fun. Looks a little rich on the oil too. Thanks for sharing with us by the way as the video proceeded I would of done exactly everything you done to try and solve its irregular running and was as confused as you were but points for coming across that wire in the end and well spotted !
Great teaching video! And great example of how someone that tries to repair a problem without a strategy can cause more problems that they started with! Excellent work, and congrats! Your smile and laugh of victory made my day!!!!
I think we were all pretty perplexed trying to figure this one out. It's usually challenging to go where others have been before! Excellent troubleshooting Mustie1! Take care and thanks for posting!
I was on the phone with tech support once and the guy told me that if someone worked on it before me and it didn't get fixed I should always check his work. When you think about it, it's actually not a bad idea. 🤔
I only just found this channel but I love it. I appreciate you Mustie1. Thank you for sharing your skills knowledge and experience
This guy is a genius. I didn’t understand a lot of what he was doing but the video was so interesting I had to watch to the end just to see if would solve the problem. He has a lot of patience, i would’ve taken a sledgehammer to that thing.
I had a problem with an overflowing carb of similar design on a motorbike.
After checking the float, making numerous adjustments to float height, and checking float valve and seat repeatedly, I finally found the issue. It was a crack in the brass overflow pipe.
I discovered this by clamping the float bowl in a vise (using some wood to provide cushioning), filling the bowl with petrol, putting my finger over the end of the brass pipe, and blowing through the overflow tube - I could see bubbles coming out of the brass pipe about half-way up.
I solved it by using Araldite to glue a slightly larger ID brass pipe over the original, which I didn't want to risk trying to remove. No leaks since, and I make sure to drain the bowl after use and turn the petrol off at the fuel tap.
Small motor gas line slipped over the brass overflow pipe also works to seal the crack. Crack comes from water in the bowl freezing and splitting the brass pipe.
The only true bit of the story about this scooter was that it had only done 500 miles ... Mustie - your combination of small-engine genius and absolute stick-at-it-ness is totally inspiring. These episodes you put together are like visiting with a mate in his workshop for a while for a mix of coffee and carbon monoxide. Intoxicating ... and have been since the beginning in your home garage. Thank you from the UK.
These scooters are the easiest things to get running. I bought one for $200 with no spark, pretty new it was a 2020 150cc with under 200 miles, bought a coil and CDI for less than $20 and it fired up and ran great!
You inspire me to dig further in my mechanical explorations. you are a great mechanic and the main reason is that you are curious and persistent...
Hi Mustie1, that exhaust is a expansion model, designed to increase counterpressure to the exhaust port. It's what the cool kids want, to make their scooters faster and flashier. Benelli is an Italian motorbike-builder. They used to produce, next tot mopeds, beautiful six-in-line motorbikes.
I longed for a six cylynder Benelli 750 back in the day.
Awesome Video. I learned more about 2 strokes in 90 minutes than I have in 40 years of living. Thank you.
Once you get this 100% sorted, I'm sure it will sell quick. Very low miles. Thanks for the great video, you start my Sundays right !!
You can still see what’s left of the nubs on the rear tire!
The bolt on the exhaust is a sheetr-off bolt. Usually used on ignition barrels on cars so when tightened up, the head snapt off and the barrel cannot be removed by thieves, unless they come prepared with a hammer and chisel.
which they did in my case. how do i know? they didn't bring their own car battery..
hi Ian PK . same bolts in UK.also
@@rogerwale4827 I am in UK, Thats how I know what they are. :).
Hey Mustie,
You sure put this through the ringer & left nothing left to the imagination ! Bravo for your not giving up !
Ive NEVER had more fun than I did riding a step-through moped through a forest trail. Its got no business being there but 15mph on one of those feels like 100mph on a dirt bike.
It was obvious that he had thoughts of not figuring this one out. I was probably almost as thrilled as he was when found the rev issue!! Also... I actually get motivated every week to get shit done because Mustie1 pushes through and doesn't make excuses. Well, at least none that we see :)
There's no way he wouldn't have figured it out, eventually. A scooter is way too simple of a machine for his knowledge, he would've taken it apart bit by bit until he found what's wrong.
around 40:00 when it starts it's a misfire situation and to me it sounds electric and that would push me into a rev limiter issue or electronics. Some mopeds do have a rev limiter.
By the way I did experience a similar behavior on a moped I once had with breaker points - the axle the point arm rotated on was corroded and made the arm move too slow. Decent idle, no rev and when revving it did sound the same.
I worked on scoots for about a decade. It was fun watching someone make overqualfied noob mistakes like i did. You should be going closer to 45 on that. They like to put restrictions in different places. Either a main jet that is too small. A washer that restricts the exhaust or a washer in the variator. We used to work those 50cc 2 strokes up like you wouldnt believe. One time i took off on a test ride on the most tuned one we ever did i almost lost it on take off. Im glad i was about 250lbs at the time to keep the wheel down
I learn so much watching this channel. Stuff I would never have had access to otherwise. It is extremely interesting to see how many different ways the engine designers come up with for the internal combustion engine.
Awesome video! Please do a follow-up video on this one. I want to see the final repairs and see it run good.
I was convinced from the start of this video that the ignition timing was at fault. I suppose I was wrong, but it was an ignition fault at least. Great work and well done.
Good morning MUSTIE and all the MUSTIE followers !
GOOD MORNING!
Hi Jason ! 😊
That is pretty darn cool! I'm surprised that just a crossed wire would do that. Live and learn.
Cliffhanger this was!!
Thanks for the great content, as always.
I firstfound you doing the red Karman Gia, and followed most of your projects since. Yourknowledge is amazing, be it new or old junkers. Great job every time sir.
Not uncommon a repair turns out to be a correction of previous repair attempts.
Well done 🙂
This was a good one! Challenging, but you can't stump Mustie1! LETS GO! You had me clapping the moment those RPMs came up and that back tire started spinning 😄 had a huge smile on my face. The sense of accomplishment is such a great feeling. As an Automotive Technician I can relate to that feeling of figuring out a problem that at first has you stumped. Love it! Keep the "will it run" videos coming sir!
It looked to me like the float level was too high, and lowering the float level should have a similar effect as lowering the float needle, which helped, but not enough. The excess oil also seemed awfully persistent to be just in the crankcase, which makes me think the oil pump may be out of adjustment or defectively pumping too much oil.
1. Drain tank of all fuel, and make sure only oil enter carb by way of oil tank. 2. Check for any restrictions in exhaust system. 3. 3. Check cylinder for carbon deposit boil-up nr=ear exhaust port. 4. Remove variation and check to see if all roller weights are rolling properly. 5. I have yet to see rear wheel spin up under acceleration. Make sure there are no restrictions to rolling of rear wheel under throttle opening.
This is about the best troubleshoot comment I have seen yet….
The engine might be running rich because of the exhaust constriction or the Bistarter. If you take that half moon shaped exhaust restriction off the cylinder, that's what makes this a "Moped" rated scooter in many states legally. The bistarter is the plunger you were calling a solenoid, it's not. Hook it up to 12 volts for a few minutes, check for length, should get longer after 5 minutes Should be able to run close to 30~35 mph with that plate exhaust port removed.
Also check the engine pulley on the CVT, they sometimes put a metal ring in that prevents the CVT flyweights from running the entire length of their operation "ramps" also restricting the top speed to about 20~25mph.
Yes it can constrict the flow of exhaust, but the purpose of the "half moon exhaust" is because its called an expansion chamber and is required in 2 stroke engines to help with scavenging to use backpressure to push unburnt fuel back into the engine
Guys, it is CDI rpm limited.... :)
Listen I've worked at a Genuine and SYM dealer, and you don't leave the little port restriction in if you want the full affect of the expansion chamber's pressure waves to work. I've owned enough 2 stroke bikes to know this.
@@tauncfester3022 My bad dude, I misunderstood what you wrote. Yea that makes complete sense if you remove the port restriction, its only there by law anyways to reduce the power output
Nice edited video. I enjoy the longer videos where you show every step but this one you definitely edited but still has the longer run time. Nice and cleanly done. I thought it was the choke the whole time, with the loss of throttle control.
If you take a hollow ground flat tip screwdriver (or regrind a round shank screwdriver) so the tip looks like )( viewed from the side it will grip carb jets rather than smear the slots. My Vincent-restorer mentor invented that trick in the 1960s when most jets were slotted and it works a treat if you do a tidy job of grinding.
Those Clore JNC 660 jump packs are outstanding and Clore sell replacement parts. They're easy to work on too. I bought my first in 2014 and replaced the batteries last year. I bought a second mostly in case something happens to the company.
I love watching your videos, how you explain things and actually show your wins and fails. I have learned so much from you, even though my Biking days and fixing cars are well over, Just watching you fixing up stuff is very theraputic. + you get some great freebies- so you win, and we your audince win!
Another outstanding video again
Thank you for the education
Alot of people appreciate your time to help
Oh man, I had Benelli scooter about 8-10 years ago. They are actually pretty decent scooters, at least mine was back then. Absolutely loved it as a quick commuter to the shops in Brooklyn.
Only thing that sucks about Mustie's videos is that they are over too quickly.
Do what I do. Go back and watch older videos. When you've watched them all start over. lol
Over to quickly and with the exception of one video.. are all on TH-cam, there has to be a easy way to upload to both Rumble and TH-cam.. I guess that's a good problem to have though.
I binged watched a shed load of his videos a while back ...best 7 hours iv had in ages
@@eric_seguin Same,videos are so satisfying haha 😃
Damn dude! That was an amazing effort and success! Great job! Always astounded at your skill and dedication to not being bested by other folks cast offs. Thank you for the great entertainment!
Seeing as it was really low miles, my guess was straight up electrical problem, switched wires is a tough one to find, nice work 🙂👍
Good on you for getting it running again, its quite a feeling!
However, when you finally figured out the reason, I cant help to get unreasonably angry, when "pre-owners" mess about with electronics, and screwing up because of their incompetence.
Yeah....been there, done that.
Don't get angry. Everyone screws up sometimes? Life is too short, enjoy while we can.
PS- Your right it pisses me off too !!! LOL!
"unreasonably" ...
Have you never made a mistake?
At least they tried! And they nearly had it: a simple check of THEIR OWN wiring would have fixed it.
@@grantperkins368 Yeah, and they never did, go figure...
Sounds like the CVT has a limiter- spacer on it to limit ratio change. Lots of markets got these because of local market regulations. There should be info online on how to get rid of this limiter hardware.
Maybe you can get a tuning kit for this thing? Malossi? bigger carb. + jetting? exhaust seems OK.
These things can easily be made to run 50mph
Often disconnecting 1 wire is all you need to do. I know that on my Yamaha mint 25KMH version is limited to 35KMh it is the blue wire of the CDI I only use 1/5 of my gas handle but the 45 versions (limited 50) they use more travel. but they do sound like this on limiting by missing fire moments to limit speed/ engine ref.
Unfortunately it's only a CDI replacement. From the factory, they are rpm limited
That’s probably what started this whole “project” with the previous owner… trying to swap in performance parts..
@@Montimoped It depends, some can be fooled with 1 wire. not all though. As M]my Mint only needs 1 wire to be disconnected but Might be different in this one.
Great video as always. a little FYI...the black cdi boxes come with around 5000 rpm rev limiter built in,,,that's why people change them out. Try the red cdi box.
Good catch on the wiring. Did you ever check to see if it actually had 2 stroke oil in the tank ? I've seen everything from motor oil to gear oil put in 2 stroke tanks.
The smell would probably give a bit of a clue... I've done it myself in a pinch when I was a young lad & didn't know any better... 🙄😂
With the amount of smoke coming from the exhaust I wonder if they put premix fuel in the tank with the result that it's getting double (or more) oil.
That's what I thought.
It'll foul that plug pretty fast with injection+premix, (learned lesson on my polaris when paranoid of ancient injection pump)
It's probably what started the problems and new parts, wrong fitting etc followed from there.
Well done - correcting other people’s wrongs - specially to do with wiring is an impossible task - but you did it.
Congratulations Mustie1...your knowledge kicked in and fixed the unfixable! I honestly believe you could fix a bad day!!! THANKS for all you do!
I like it that you put the camera EXACTLY where we can see exactly what we need to see, plus, you treat the camera like a person...you ask our opinion, sometimes, and I catch myself verbally answering you. It's THAT personable! You explain everything and how stuff works, and theory stuff, and...well, nobody else has anything like you do or as good of content as you do. You don't adlib, nor have nauseous music playing in the background. You speed up the feed thru repetitive time consuming procedures. It's still there, where we can still SEE how you did...whatever, it just shortens the time it would take for a fullness of video. Your editing is superb and all of it is VERY MUCH APPRECIATED !!!
He fixes my bad day every time i watch him it cheers me up
That engine is a horizontal minarelli. Found in tons of scooters. It was the motor in most 2 stroke yamaha scooters as well. Pretty much the same motor as a bws50 yamaha.
Its a clone Minarelli Horizontal air cooled.. In the 90er they used the original one. Some parts of the original minarelli will also fit on this clone engine.. The cilinder looks to be the same. (only the clone using P12 piston barrel.. And the old using P10.
Yup.I have a 2 stroke Yamaha BWS been sitting in my garage for about 10 years, it has that engine. It was running when I parked it, I'll get around to starting it up and selling it sometime.
Hey mustie, long time admirer here... I think the science community could use your skills with their problems with FUSION. You could probably have a FUSION REACTOR firing in a video or two! Awesome display of diagnostics! Thanks so much and this was fun.."kick my ass"....No way!
You are 1 of the smartest people i know on TH-cam when it comes to fixing stuff and or figuring out stuff i think its amazing what you do i myself was a handy man back in the 80s and 90s if i couldn't fix it it wasn't worth fixing i love watching your videos always will great work always ✌🇺🇸
Question everything about what previous 'mechanics' have done when you step into a partially disassembled machine. Good work, good info, good entertainment.
This is the best explanation I've ever heard. Great video! I'm about to do my carbs on an 85 interceptor 700. It doesn't look fun. But I'm confident.
Mustie is a legend! I wish I had his talent! Love every video he does - especially the ‘will it run’ ones…. Well done for fixing this. Don’t think I could’ve fixed it - keep the videos coming 👍👍👍
I have his talent but still love watching him tackle his challenges, it reminds me so much of me … but hey anyone can learn this, just find some junk/treasures to restore … practice can make you as good as Mustie …. Also pay attention to the details in his videos and you will do well …
I would try decoking the exhaust with a caustic soda solution. My old MZ 2-stroke used to refuse to rev when the silencer needed a decoke, easy to do and doesn't cost much.
Tell me more about how to. Last time i used 2 propane torches and smoked it red but using a solution sound easier
@@RIMHQ-YT Remove exhaust from bike. Block one end of the exhaust with a potato. Make up a strong solution of caustic soda and pour into the exhaust until full. Leave overnight, then remove potato and drain. You may need to repeat a couple of times. Keep the caustic away from aluminium as it attacks it.
@@WinstonSmith2024 awesome. Thankyou!! Use a potato was a great idea!!
I bought a 150 for my daughter with 14 miles. The dealer couldn't get it to run so they sold it for $600.00.
The only adjustment was the idle. So I got a slightly larger carb with interchangeable orifice seats. With the larger carb and a 4x larger jet orifice, it can run 60+mph with me and my wife on it.
Surprised me, I'm 6'3"/250lbs and she's 130lbs and it pulls off from a stop very well.
so basically the most common problems with scooters or simple motors in general are carburetors being messed up, maybe some gaskets(low compression problems) and electrical problems. If that is the case i learned a lot from this video. Thank you bro! 1.5h spent with quality first hand content.
No; The biggest problem with scooters/bikes is that at least 2 other people have messed with it before you get it...The original problem was the air cleaner not seating on the carb properly, and the people before messed with everything BUT what was originally wrong; Not putting it back together properly...
Often on 50cc scooters the 'variator' (the front pulley) has a spacer washer to prevent the front pulley halves coming too close together, and this limits the top speed of the bike. The 50cc bike I had went from a top speed of 30mph to 50mph just by removing this. Mine already had the exhaust restrictor removed as these aren't required in the UK. This might be worth 10mph as well.
I was thinking the same,plz remove the speed limiter! I hate that cos it revs the engine to the max and the bike is not moving. Totally agree that bike should reach 50mph no problem. And yes,many of those exhaust had a sound trap you could remove too and the engine will be happier. With some simple mods you could have a very fun bike to ride.
Yes, very likely as you can clearly see the outer perimeter of the variator pulley halves have never had the belt reach the top because there's still a shiny new finish where the lower portion has been dulled by belt contact. Pull that spacer from between the two halves to get full transmission range and a higher top speed. There may still be a restrictor inside the exhaust too.
I had a Yamati very similar with a similar start up issue and I believe my issue was the enricher. The fix was to use the kick starter until it started sputtering and then lay the scooter on its left side at about a 45 degree angle. I don't know if this moved the fuel mix around in a weird way but if I did this it would idle and run normally. I didn't have to do this every time I started it, just the initial time if it had been sitting up for a week or more. If I went to start it the next day, it would be fine. I think it also had a small leak in the oil injector shutoff that would allow more oil into the carb (gravity) when it was sitting up. Mine topped out at 45mph. I had another scooter that did that same break-up issue on full throttle and I chased what I thought was a carb issue and turns out it was a faulty spark plug.
Love your determination and detective work. Great job!👍🏻
The auto choke works as it warms up .When cold, it has the port open to allow more fuel to pass into the carb. When it warms up, the plunger is pushed out and the needle closes the port for the extra fuel. If you leave the scooter with the ignition on when it is cold, it will close the choke and it would be difficult to start. I found this out when mine didnt start after leaving the ignition switched on. Takes ages for it to cool down to be able to start it.
I thought it was the choke right off the bat, and I'm not way thru the video!
@@michaelhartzell9758 I would never have thought it was the wires on the CDI. The choke was working fine, but if ignition is left on, then it wont start unless the air is restricted. I done mine the otehr day and found I jammed the choke in the carb after stripping and cleaning hte carb. Blocked of fthe air at the carb and it started, I checked my choke and now it startes first press of the key.
Mine has the opposite problem. A cold start on a hot day, no problem, fires right up. On a cold day, I don't even bother with the electric start: I could drain the battery trying to start it. Instead I have to kick it over maybe 50 times before it fires. The choke doesn't run off the battery. It runs off one coil in the magneto, so once it starts the mag will close the choke and keep it closed as long as it's running. In other words, the engine doesn't like the extra fuel when trying to start it in the cold. The 50 kicks activates the mag and eventually warms and closes the choke. I'm thinking of sending battery power to it through a switch to warm it up before trying to cold start it. We'll see.....
@@curbmassa If you watch Samodel on youtube, he shows how to make a manual choke using an electric one. He is a cleaver moped builder. :)
When it fired, i could smell the 2-stroke oil! A memory of 50-odd years ago.
Great video. Can watch you all day mate!
Nice! You might want to look at the spacing between the ignition pick-up and the rotor. Too much spacing may lead to a poor signal at high RPMs.
Ignition is my guess spark plug or ignition
Can there be any problems with the pick-up being too close? assuming there is still an air gap, of course
A technique I've seen is to slide a piece of paper between the flywheel and pickup, jam them as close together as possible, and remove the paper
Man, your tinkering skills are on God level! I'm almost inspired to start tinkering on my 200cc Chinese scooter. I've written it once before years back, but it's pretty much been sitting for about a good five six years. Thanks for the great video, they're all inspirations.
Italian 50cc scooters have "restrictors", typically a restriction in the exhaust (if i remember correctly also that small pipe coming off the exhaust should be removed and the hole plugged) and a ring to limit the travel in the variable pulley attached to the crankshaft
Back in the day, that was true but the newer bikes from over here use "electronics" to govern RPM ... that little "Red Box" the previous owner installed (and fried by reverse wiring) is where it is accomplished now.
yeah this is no china clone, this is quality stuff
@@whoknows8225 Its a clone from the real minarelli engine.
Yes, you're absolutely right, you can easily hear the exhaust is still restricted, that kind of exhaust is much louder when you remove it.
Awesome diagnosis video! Sidenote-your voice is awesome for radio or podcasting
25:01 "Let's poke it with a stick..." Finally, an engineering concept I can relate too 😂
The auto choke has a wax thermostat. when cold the chokes on, power is applied when running, which melts the wax and closes the choke via a heating element.