Hi both. Please check cam timing with a degree disc. After the effort you guys have expended i would not be taking anything for granted.....could be this has a custom cam......
Hello Frank, two ideas,first if the camshaft is non standard it will require larger valve clearances ie Megacycle or Combat spec.The other thing is with the Mikuni you are using it it crucial the choke plunger is working correctly, it maybe worth swapping the one from your bike as you know this is OK. Good luck Keith from the UK.
Hello Frank and Kevin Big fan of your channel. Not to sound too much like an armchair mechanic but I just changed out my Boyer ignition for a trispark and coil from Colorado Norton Works and what a world of difference. It takes a lot more fiddling to set it but once it’s there it’s a first kick start almost every time. Good luck with the green gremlin oops I mean goddess. 😊
On a previous video I commented the timing scale on the primary covers can be out of accuracy by 3-6 degrees. That may be enough to make the difference in the starting ability. Need to do the timing disk and piston stop procedure to confirm if scale is giving you the correct number.
I have watched several of your previous videos on that thing. Knowing what you have changed and inspected, I wonder if the owner had that engine rebuilt and had new cams installed? I will be the very first to admit that I know very little about Norton's, but I can't help but wonder is it might be advisable to put a degree wheel on it and see if the cams are in fact opening and closing the valves at the proper time. I might add that I spent 35 years as a motorcycle mechanic and when you hit the wall like you have with this one, it is sometimes better to step back and look outside the box.
I’ve owned my 850 Commando for 50 years and have never experienced anything like you guys are going through with this bike. In theory, the internal combustion engine is diabolically simple: you just need fuel, air, compression and spark in the right amounts at the right time and an ICE should run. However, the key word is diabolical. I don’t pretend to have any specific advice to offer other than to state the obvious; proceed as you have been doing, be methodical and work through each system, fuel, air, compression, electrical, and timing individually to try to eliminate that system as a source of concern. I suspect that when your efforts finally pay off, it’s probably going to be something frustratingly simple. Good luck.
That Green Goddess is treating you guys more like Poison Ivy! Just a shot in the dark here, but sometimes the generator rotors have 2 timing marks on 'em... could it be 180 degrees out? Take a break from it for a couple of days, you guys have earned it. This is why I like Amal carbs and standard ignition...and the fact that I'm a cave man. ;)
20:32 to 21:30. That was me every morning in 1979, about to miss the first lecture of the day in final year. That's why I sold my Commando and went back to Yamaha.
So,after all that kicking over,are the plugs fouled up,they should be, if you try giving it a dozen kicks on full choke and wide open throttle then check the plugs for fouling, they should be if not it's a fuelling issue. 22:26
I feel your pain. Maybe a leak down test to determine the missing compression? If the leak down test comes up good then the cam profile is suspect. Or the compression ratio is off because of mis matched pistons to stroke? You could CC the head combustion chamber and the tdc piston cylinder area to determine CR. 90 psi points to a 6:1 CR. Were the valves checked for leak through when you had the head off? I did not see that. That compression should be up about 150 - 175 as you know. Please keep up the good work and the videos. Happy Hunting Cheers
OH! You were Sooooo right! Found the B/W and B/Y wires reversed at the black box. We (I) must have done it! And all this time I swore the wiring was correct. I wish I had paid attention sooner.
That's a tough one. Seems like it should start even with that compression. When my 1978 Bonneville is cold, it gets around 90 psi on each cylinder during a compression test. When it's warm I'll get 155 on each cylinder.
As it is now Trigger’s broom (a quote from British TV) do you think it’s worth removing the timing gears, making sure they are right for the bike? Could the dot be something added by a P.O. rather than stock? If you have a spare set of timing gears, pop them in?
Try an electrical continuity test through the kill switch. My Norton manual states the engine will fire, but immediately cut out if the switch is set to kill. This engine has previously popped, but not run.
hi are you getting big fat blue sparks across a spark plug tip grounded to head? been a long time but used to have some bikes that just refused to start without pushing in 2nd or 3rd gear. big fan of ign points to this day on these bikes
I believe that your issue may be with spark timing / condition.Suggest that you carefully check the following:-1/. Ignition circuit wiring & potential voltage drops across components ( e.g ignition switch ).Test coils. ( 3 tips.....1/. .Swap the plug leads over. 2/ .Boyers recommend 6v coils, 3/. Connect the module ground wire direct to the battery NOT the frame.
Check the ignition timing. I think you will find it should be 28 degrees BTDC for points and 31 degrees BTDC for electronic ignition. Shouldn't stop it from starting but worth a try.
I asked a well respected motorcycle mechanic friend of mine to watch the video, and here's his response: "There is not enough voltage for the electronic ignition. Needs to be at least 12.8 volts with the switch on."
First, thank you for caring enough to have your friend look at the video. (I am very serious there.) Your friend is sorta correct. The electronic ignitions do need a strong, well charged battery. The specs I've seen are a good solid 10.5 to 11 volts minimum for dependable starting. Anything above 10 to 11 volts is a bonus. Good old mechanical points will fire the plugs with the battery way down to 5, 6, 7 volts which is which is an advantage they offer. "Greenie" as we lovingly call her, has a new battery and it is fully charged. HOWEVER, the next time we get her on the lift we are going to do a complete "start over" trouble shooting process. A 24-hour battery charge, all new gas, check the ignition timing mark with a degree wheel, reset the static timing, double and triple check the pilot jet for blockage, and then . . . . well, we will think of something. Believe me, if the no-start problem turns out to be something we did wrong that is really simple stupid, I will video tape and publish it! I hope to get her up on the lift next week. Stand by!
Actually it is a good question. (Back when we were young and dumb we thought it was funny as heck to swap a buddy's magneto leads. Doesn't seem as funny now.) But in this case it has an Electronic Ignition System. Both plugs fire at the same time. It's called a "wasted spark" system.
The Green Goblin continues to taunt our heros
Hi both. Please check cam timing with a degree disc. After the effort you guys have expended i would not be taking anything for granted.....could be this has a custom cam......
Hello Frank, two ideas,first if the camshaft is non standard it will require larger valve clearances ie Megacycle or Combat spec.The other thing is with the Mikuni you are using it it crucial the choke plunger is working correctly, it maybe worth swapping the one from your bike as you know this is OK. Good luck Keith from the UK.
Hello Frank and Kevin
Big fan of your channel. Not to sound too much like an armchair mechanic but I just changed out my Boyer ignition for a trispark and coil from Colorado Norton Works and what a world of difference. It takes a lot more fiddling to set it but once it’s there it’s a first kick start almost every time.
Good luck with the green gremlin oops I mean goddess. 😊
On a previous video I commented the timing scale on the primary covers can be out of accuracy by 3-6 degrees. That may be enough to make the difference in the starting ability. Need to do the timing disk and piston stop procedure to confirm if scale is giving you the correct number.
Agree. Going to open the primary and check the indicator/alternator mark next. Gotta get a couple of other bikes out first. Then back to the Goddess.
This is like watching a good detective show. We can't wait for the surprise ending.
I have watched several of your previous videos on that thing. Knowing what you have changed and inspected, I wonder if the owner had that engine rebuilt and had new cams installed? I will be the very first to admit that I know very little about Norton's, but I can't help but wonder is it might be advisable to put a degree wheel on it and see if the cams are in fact opening and closing the valves at the proper time. I might add that I spent 35 years as a motorcycle mechanic and when you hit the wall like you have with this one, it is sometimes better to step back and look outside the box.
I’ve owned my 850 Commando for 50 years and have never experienced anything like you guys are going through with this bike. In theory, the internal combustion engine is diabolically simple: you just need fuel, air, compression and spark in the right amounts at the right time and an ICE should run. However, the key word is diabolical. I don’t pretend to have any specific advice to offer other than to state the obvious; proceed as you have been doing, be methodical and work through each system, fuel, air, compression, electrical, and timing individually to try to eliminate that system as a source of concern. I suspect that when your efforts finally pay off, it’s probably going to be something frustratingly simple. Good luck.
I agree with Keith, What cam is in it. Just try to go with more clearance on the valves.
That Green Goddess is treating you guys more like Poison Ivy!
Just a shot in the dark here, but sometimes the generator rotors have 2 timing marks on 'em... could it be 180 degrees out?
Take a break from it for a couple of days, you guys have earned it.
This is why I like Amal carbs and standard ignition...and the fact that I'm a cave man. ;)
Yes, simplicity is looking better and better.
20:32 to 21:30. That was me every morning in 1979, about to miss the first lecture of the day in final year. That's why I sold my Commando and went back to Yamaha.
So,after all that kicking over,are the plugs fouled up,they should be, if you try giving it a dozen kicks on full choke and wide open throttle then check the plugs for fouling, they should be if not it's a fuelling issue. 22:26
I feel your pain. Maybe a leak down test to determine the missing compression? If the leak down test comes up good then the cam profile is suspect. Or the compression ratio is off because of mis matched pistons to stroke? You could CC the head combustion chamber and the tdc piston cylinder area to determine CR. 90 psi points to a 6:1 CR. Were the valves checked for leak through when you had the head off? I did not see that. That compression should be up about 150 - 175 as you know. Please keep up the good work and the videos. Happy Hunting Cheers
No valve sealing was not checked , at least not on video.
Have you checked that the tdc mark is correct
is the spark plugs wet.....if not squirt some gas in the spark plug holes......use that choke
Yes l asked about wet plugs 3 videos ago. However it didn't respond to carb cleaner did it.
With my boyer i went through days of pops and bangs when the sensor/pick up cables were reversed.... worth a check....
And it did spark....
OH! You were Sooooo right! Found the B/W and B/Y wires reversed at the black box. We (I) must have done it! And all this time I swore the wiring was correct. I wish I had paid attention sooner.
Have you considered fitting a test carb instead of the aftermarket Mikuni? Perhaps the jetting is incorrect for the bike.
That's a tough one. Seems like it should start even with that compression. When my 1978 Bonneville is cold, it gets around 90 psi on each cylinder during a compression test. When it's warm I'll get 155 on each cylinder.
As it is now Trigger’s broom (a quote from British TV) do you think it’s worth removing the timing gears, making sure they are right for the bike? Could the dot be something added by a P.O. rather than stock? If you have a spare set of timing gears, pop them in?
Is there not a push rod comb for Norton Commandos(I used to have one for BSA a10)?
No, but the push rod shaft is made so it USUALLY guides the push rods directly to the rockers. The trouble this time was unusual.
Try an electrical continuity test through the kill switch. My Norton manual states the engine will fire, but immediately cut out if the switch is set to kill. This engine has previously popped, but not run.
Also, try some fresh fuel.
hi are you getting big fat blue sparks across a spark plug tip grounded to head? been a long time but used to have some bikes that just refused to start without pushing in 2nd or 3rd gear. big fan of ign points to this day on these bikes
Have you got the plug leads the right way round ??
Yes. It has an Electronic Ignition System. Both plugs fire at the same time. It's called a "wasted spark" system.
I believe that your issue may be with spark timing / condition.Suggest that you carefully check the following:-1/. Ignition circuit wiring & potential voltage drops across components ( e.g ignition switch ).Test coils. ( 3 tips.....1/. .Swap the plug leads over. 2/ .Boyers recommend 6v coils, 3/. Connect the module ground wire direct to the battery NOT the frame.
They did this in another video.
Are you reluctant to use a roller starter..?? Im assuming you have one.
New plugs? Maybe I missed that in the saga so far.
Your comp gauge is faulty, try another.The kicker is holding Kevins weight so the comp is way higher than 95/100.
Could be true. My favorite gauge died and this is my back-up.
Check the ignition timing. I think you will find it should be 28 degrees BTDC for points and 31 degrees BTDC for electronic ignition. Shouldn't stop it from starting but worth a try.
I asked a well respected motorcycle mechanic friend of mine to watch the video, and here's his response: "There is not enough voltage for the electronic ignition. Needs to be at least 12.8 volts with the switch on."
Great point..you and you're buddy may have something there...if I'm betting, this is where my chip goes. They seem to have covered all else.
I noticed you didn't receive a response.
First, thank you for caring enough to have your friend look at the video. (I am very serious there.)
Your friend is sorta correct. The electronic ignitions do need a strong, well charged battery. The specs I've seen are a good solid 10.5 to 11 volts minimum for dependable starting. Anything above 10 to 11 volts is a bonus. Good old mechanical points will fire the plugs with the battery way down to 5, 6, 7 volts which is which is an advantage they offer. "Greenie" as we lovingly call her, has a new battery and it is fully charged. HOWEVER, the next time we get her on the lift we are going to do a complete "start over" trouble shooting process. A 24-hour battery charge, all new gas, check the ignition timing mark with a degree wheel, reset the static timing, double and triple check the pilot jet for blockage, and then . . . . well, we will think of something. Believe me, if the no-start problem turns out to be something we did wrong that is really simple stupid, I will video tape and publish it! I hope to get her up on the lift next week. Stand by!
Oh yeah, and new plugs again.
Have you tried fresh gas?
Yes, but I may just change it again.
No choke
Tickle it more
Give it more throttle
Stupid suggestion - try swapping the plug leads.
Actually it is a good question. (Back when we were young and dumb we thought it was funny as heck to swap a buddy's magneto leads. Doesn't seem as funny now.) But in this case it has an Electronic Ignition System. Both plugs fire at the same time. It's called a "wasted spark" system.
carb cleaner not the same as starting fluid
Does he mean brake cleaner? Not carb cleaner.
😅
It needs an electric starter.😂
It's got no ⛽ gas in it. HaHaHa😂😂