Norton Commando 1969 timing issues

mean gene

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All good info. I'm from the KISS school. Keep It Simple Stupid. If it is kicking over easily you don't have enough timing advance, if when kicking it tries to throw you over the handle bars you have to much advance. Good luck it's hard when you are following someone else's rebuild.
 
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If it is kicking over easily you don't have enough timing advance
I must have missed where he said it kicks over very easily.
My combat (warm) starts even by hand and made 47RWHP.
A good ignition curve allows that @ 7-10 degrees btdc.
Unfortunatly an old black box analog boyer does not do that.
 
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Also, maybe I missed it, but what's the story on the plugs themselves? Are they new? I've seen reference to plug leads and plug holes in this thread, but no discussion of whether the ones you're using are good new ones or ancient ones, or crappy ones. I've had some bad plugs that didn't look bad.
 

illf8ed

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My ‘69 750 S had been idling very poorly. Wasn’t sure if it was carb or ignition. I had an extra TriSpark ignition, so removed the points ignition and stock 12v coils. Stole the 6v coils from my ‘72. Wow what a change. The problem was not carbs.
 
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It’s possible you are flooding the engine. Quick check for this if it doesn’t start in a few kicks....open the throttle wide open. It should start in one or two kicks. If not at least that’s eliminated.
Thanks I tried that already with no success
 
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Also, maybe I missed it, but what's the story on the plugs themselves? Are they new? I've seen reference to plug leads and plug holes in this thread, but no discussion of whether the ones you're using are good new ones or ancient ones, or crappy ones. I've had some bad plugs that didn't look bad.
The spark plugs were new but the leads came with the bike but seem to be in good condition
 
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Use alternator timing marks OPPOSITE the crankshaft key put some marker paint on that pad
If you are sure the timing mark is at 26-28 degrees BTDC Then with the pick up plate set middle of adjustment, then put magnet white dot in CW hole above pickup, make white dot on the CW edge of the Cw hole.
plug gap .020 for testing make sure clean and dry
this is retarded a bit and should start easily from an ignition stand point, if engine is mechanically good and carbs are OK.
If it does not start then I would suspect the pickup wires are reversed which retards the the timing 20-30 degrees and it will never run.
but might make it bang/backfire on intake valve just opening ?
then swap the pick up wires
4 kicks each max and it should run. if not, do a compression check 120 psi minimum
I will try it today and let you know. Thanks
 
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The problem was not carbs.
OT from original post but...
please finish report details: HV wires? plugs? Who tested and maintained the old points and bike wiring ? What was your idle advance timing and RPM at idle for points VS EI? Which affects vacuum therefore indirectly carbs...The interaction is unavoidable!
Will assume you did NOT touch idle mix or speed screws AT ALL....
 
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FWIW, 11.7VDC on the battery means the battery is only around 25% charged - IOW, it's not far from a dead battery. So if you haven't, charge it as suggested earlier. Leaving the charger connected while the engine is running is perfectly OK. Heck, you could connect 10 battery chargers to the battery with the engine running (or not) and no damage will occur ASSUMING the chargers themselves are not faulty.
 

Carl H

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Despite my best efforts to kick start bikes now a days, I just can't do it Weather they have points or Boyers. My high tech solution is to get a friend with a bigger body and better legs to kick them for me. They start right up. So knowing that I'm glad to have my MK3 and a new CNW E start in my Combat, They fire up quite nicely and save my knees and hips from needed a replacement for a few more years. So after going through all the advice and different tries on a starting problem, Try getting some one with a better leg. It works for me.
 
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You should fully charge it. The Boyer is very sensitive to low battery voltage.
Do you have any independent research to offer to back up your statement?

The bike should start and run OK at 11.7v (if at the black analog boyer box)
My article (by David Comeau, Jan 2001) shows gross TIMING sensitivity below 10.8v but the spark continues typically down to 8v before it would fail to ignite the charge, probably causing the severe kick back we all enjoy :mad:....
http://atlanticgreen.com/
http://atlanticgreen.com/boyerevolved.htm
http://atlanticgreen.com/images/boyerjitter.gif
boyerjitter.gif
 
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OT from original post but...
please finish report details: HV wires? plugs? Who tested and maintained the old points and bike wiring ? What was your idle advance timing and RPM at idle for points VS EI? Which affects vacuum therefore indirectly carbs...The interaction is unavoidable!
Will assume you did NOT touch idle mix or speed screws AT ALL....
I never seen this bike running. I got from a dealer and not from the original owner. The previous owner was restoring the bike but never managed to run it properly. I set the carbs after cleaning and try to start the bike. It didn't start so I reset the timing. Bought new spark plugs and the leads seemed fine. Never got to see the old points or to see the bike running.
 
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Do you have any independent research to offer to back up your statement?

The bike should start and run OK at 11.7v (if at the black analog boyer box)
My article (by David Comeau, Jan 2001) shows gross TIMING sensitivity below 10.8v but the spark continues typically down to 8v before it would fail to ignite the charge, probably causing the severe kick back we all enjoy :mad:....
http://atlanticgreen.com/
http://atlanticgreen.com/boyerevolved.htm
http://atlanticgreen.com/images/boyerjitter.gif
boyerjitter.gif
Awesome - my first attack post from DynoDave :)! I think that's how you know you made it on Access Norton these days.

How do you know I wasn't referring to gross timing sensitivity? And yes, I do in fact have some independently generated data to offer to back up my statement: I have personally experienced issues with a Boyer as a direct result of low battery voltage, and well above 8 volts. But perhaps most importantly, the suggestion I made was to try fully charging the battery, which is an easy step that won't hurt anything, and it just might help.

Cheers!
 
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L.A.B.

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OT from original post but...
please finish report details: HV wires? plugs? Who tested and maintained the old points and bike wiring ? What was your idle advance timing and RPM at idle for points VS EI? Which affects vacuum therefore indirectly carbs...The interaction is unavoidable!
Will assume you did NOT touch idle mix or speed screws AT ALL....

I never seen this bike running. I got from a dealer and not from the original owner. The previous owner was restoring the bike but never managed to run it properly. I set the carbs after cleaning and try to start the bike. It didn't start so I reset the timing. Bought new spark plugs and the leads seemed fine. Never got to see the old points or to see the bike running.

I believe dynodave's post was a reply to illf8ed.
 
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I wanna thank you all for your help!
At this point I am starting to think there might be something wrong with my electronic ignition.
I reset the advance to 31 degrees like recommended for BOYER EI and with the spark plugs connected but out of the engine I place them against the engine head while kicking the engine in neutral continuously. All I get is a spark every 4-5 full engine turns. It should spark every time right?
How can I test the EI to make sure it works properly? Can I just hotwire one of the wires from the boyer stator plate directly on the engine head bolts to test the spark?
 

maylar

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Assuming you have 2 6v coils in series and positive ground, disconect the boyer box black wire from the coil terminal and touch a jumper wire from that coil terminal to battery negative. Each time you touch and remove the wire you should get sparks. If that works, your coils and plugs are OK.
 
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Assuming you have 2 6v coils in series and positive ground, disconect the boyer box black wire from the coil terminal and touch a jumper wire from that coil terminal to battery negative. Each time you touch and remove the wire you should get sparks. If that works, your coils and plugs are OK.
thanks I will try that right away and let you know
 

L.A.B.

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How can I test the EI to make sure it works properly?


Can I just hotwire one of the wires from the boyer stator plate directly on the engine head bolts to test the spark?

No, you need to use the scratch test in the first link.

What you could try if you haven't done so, is to connect the Boyer box negative (white) and positive (red) wires including coil positive directly to the battery also ensure there is a good engine earth/ground to the battery(+) for the spark plugs.
 
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