Norton Commando 1969 timing issues

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With the plugs out so the engine spins easily , I would expect a spark each kick. Boyer magnet rotors can be weak and will then be speed sensitive giving you the results you are getting. A new rotor has fixed this in the past for some.
 
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Sounds to me like this Norton hasn't been set up to run at all for a while.

Did you check to see if the fuel tank was full of dirt and water? Kidding, but just saying.

4 pages. Is this gonna be another it was a short under the kill button thread? ;)
 
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Hello everyone
So this is the update based on all your advises.
Charged the battery fully.
Checked again the leads from the boyer black box to the timing plate (black and white/black and yellow) just in case and they are correct.
So afterwards I tested the black box with the boyer guidelines provided by L.A.B. removed the spark plugs and placed them over the engine head in contact with the bolts. When I touched black and white against black and yellow I get a nice fat spark from both sides. So that not only tells me the black box is good but also leads and and connections right?
afterwards I checked the resistance of the timing plate and got 131. tested the one from the t140 and it was slight higher at 137. So decide to try and start the engine with the t140 plate and it made no difference. I did find a couple of washers behind the rotor magnet not sure it's relevant. Also I did the magnet test like in the description and it hold it's weight on a wrench but I can test with the one from the t140 which I am positively sure is good.
But the same story repeats itself, tune the EI to 31 degrees, tick the carbs and I get a pop and smoke from the carbs. not sure if the pop it makes it´s backfire coming from the pipes or if it's coming from the carbs. Also the carbs are moist with gas but not spitting. At the end of the day I removed the air filter to see if I could better understand what happens. I know I can set the bike on fire without them right?
I am pretty sure did all the steps of the timing correctly.
Thank you for all your support
 
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With the plugs out so the engine spins easily , I would expect a spark each kick. Boyer magnet rotors can be weak and will then be speed sensitive giving you the results you are getting. A new rotor has fixed this in the past for some.
I will test changing the rotors tomorrow but like I said it was holding it's weight like described on the test.
 
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Sounds to me like this Norton hasn't been set up to run at all for a while.

Did you check to see if the fuel tank was full of dirt and water? Kidding, but just saying.

4 pages. Is this gonna be another it was a short under the kill button thread? ;)
Fiber tank was washed by me before painting. It was sealed previously. placed in line gas filter on both taps just in case :)
 

DogT

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Just for reference, I have my original Apr 69 rotor. It won't start the bike with the points and just the capacitor or is very hard, however it will roll start. A well charged battery, even 15 years old, will start the bike with the Pazon Sure Fire. I think you said you had a Pazon, I'd try that. I know the rotor on my bike is weak, but with a good battery it shouldn't matter.

It would be interesting to know the compression. As is known, spark, correct timing, enough compression and proper fuel will start the bike. Have you tried starting fluid? Be careful with it though it will blow holes in pistons. I've used in my JD2020 diesel tractor but only with a good battery and the engine cranking.

Also, are you getting 2 compression strokes with your kick start? Mine takes 2 compressions from the kick lever to start, it won't start on the first compression. But it's very consistant, and I'm 180 lbs, but I have to get up on the pegs to push the lever all the way through, I cannot start it off to the side. Being 77 doesn't help, but I started it last week, first try after 2 years. Try avgas or 110LL racing fuel if you can find it. I have a local Sunoco station that sells it, I use it in the 2 stroke machines for yard work. Not sure what's available in EU.

Don't give up, it will happen.
 

RoadScholar

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Based on the suggestions and your great follow through I have one last question, unless I missed a post or two:

Have your checked the compression? Given that it hasn't run in a while I would expect the pressure to be on the low side, but equal (+/- 10%).

Best.
 
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I would expect a spark each kick. Boyer magnet rotors can be weak
A new rotor has fixed this in the past for some
What are folks talking about???? new/good BOYER ROTOR
Put your t140 boyer rotor and pick up and give a few kicks check for spark if not! than switch to the ignition blue box

I will test changing the rotors tomorrow but like I said it was holding it's weight like described on the test.
ROTORS ???? Don't get confused
You don't even need an alternator rotor on the engine if the battery is up?

spark spark spark spark
stay focused ignore the noise!
You obviously need spark or it will never run.
check list:
ignition 1 spark present yes/no? 2 correctly timed yes/no?

later:
fuel
compression
 

L.A.B.

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With the plugs out so the engine spins easily , I would expect a spark each kick. Boyer magnet rotors can be weak and will then be speed sensitive giving you the results you are getting. A new rotor has fixed this in the past for some.

I will test changing the rotors tomorrow but like I said it was holding it's weight like described on the test.

ROTORS ???? Don't get confused
You don't even need an alternator rotor on the engine if the battery is up?

04_testmagnet-256x192.jpg

"Hold each magnet of the rotor up to a wide flat surface (as shown). Each individual magnet should be able to support the entire weight of the rotor.
If either of the magnets will not hold the weight of the rotor, replace the rotor.
"
 
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Spray some starting fluid into it as a test.
starting fluid for the boyer?
He only has an occasional spark at the plug sitting on the head.
He is trying to make spark.....any spark regardless of timing.....
borrow t140 rotor TEST
borrow t140 boyer box TEST corrected sorry les
 
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So I just checked each of the magnets from the rotor electronic ignition and they both hold like in the picture.
Like you guys said if the battery is good it's should spark every full cycle of the engine regardless of the speed I kick the engine right?
I am only getting a spark every couple of kicks and while kicking it really hard/fast
Also tried to replace the electronic ignition stator plate and magnetic rotor from my t140 and I got no spark with the kick start. The parts look exactly the same and have the same reference but the one from the t140 is a MK4 boyer EI.
Where I am at I have no competent mechanics in these types of British Vintage bikes that I would fell comfortable to trust.
I have no means of testing compression at this point but I believe I should get a consistent spark first right?
Thank you all
 
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"Blue Boyer box" is (normally) Micro-Power (with digital coil/s)?
I don't have a blue box. I have MK3 black box electronic ignition on the norton and a MK4 Black box electronic ignition on the t140. Both with 6 volts PVL coils
 

L.A.B.

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I don't have a blue box. I have MK3 black box electronic ignition on the norton and a MK4 Black box electronic ignition on the t140. Both with 6 volts PVL coils

Yes, so I don't know why DD mentioned "blue Boyer box"?
 

Carl H

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Old starting drill for bikes. Tickle the carbs until a little gas drips out of tickler. Put choke on and kick a few times to prime it with key off. Turn key on, Most bikes start better if you have a very slightly opened carb, or none at all. When you kick you need to get it to go thru a firm hard kick so you get thru two compression cycles . ( That is what I cannot do anymore) Be sure you are not opening the throttle as you kick it. When all else fails, Try running a fused "hot wire "to the Boyer white wire if you are Positive earth directly , so you eliminate all the bikes wires and switches , be sure you have good earthing through the red wires. And scrape the battery posts/ terminals to clean shiney lead. (No oxidation on them). Also double check all the Boyer wires are hooked up properly, That should eliminate the Boyer , IF you see consistant spark and have done all the good tips others have given you. The next thing is the carbs, but that is a whole new can of worms and other mechanical issues that previous people did wrong.
 
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