Norton Commando 1969 timing issues

illf8ed

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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....
Let‘s see...... I typically try for 1000 to 1200 rpms for idle speed. Let’s assume I’m well experienced tuning idle mixture and if not I did hook up my colortune to confirm. Timing set at 28 BTDC strobing at 4,000 rpms.
 

DogT

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I like the downhill starting test. That may tell us if it's a matter of starting technique. Or it may still not run. Trouble is I'm sure the OP doesn't have a garage full of all the things that may be bad. Be prepared to get it back uphill. I had a BSA that sometimes it was the only way to start it. Luckily I lived at the top of the hill in Monterey.
 
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The reason I asked about the points position was because of the cw / ccw rotation of the rotor, so the possibility of timing on the "wrong hole" on the Boyer stator. Don't forget, the Norton ignition rotor will run in the oposite direction to your Triumph
 
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Ok so I did the teaspoon of gasoline on each hole put it all back together, primed the carbs and again I get a pop from the carbs with slight smoke but not with every kick. Like every two or three kicks
Guys I don't wanna wind anyone up and I really appreciate your patience. I am by no means an accomplished mechanic. Previously I just finished a complete rebuilt of a t140 reading forums and watching Lunmad videos on youtube but that's about it. So I apologize if I mislead in any way!
You've done a great job with the English if you are native Portuguese. I couldn't do what you are doing if I was on a Portuguese site.

I wouldn't do the cam installation check until I had fully exhausted testing the electrical and fueling side of things. It wouldn't take me long to go over my electrical system. My Norton wiring is very simple, because I did all of it. Simple in simple out. Stock or close to original old harnesses have a lot of potential for issues. Anyway, you'll stumble on a solution. It sounds to me like you are doing everything right, but I'm not sitting in your garage looking over your shoulder. Good luck with it. I hope that dealer didn't sell you a turd in need of some polishing. Turds are hard to polish.
 

Carl H

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The last two bikes I rebuilt , Even though I tried and tried , I could not get barely a mis fire let alone get it to pop off, So after checking all the usual suspects several times. I just got a bigger guy to kick it, NO problem, No sweat. I started Nortons thousands of times in my career. I even used to start my race bikes with a kick start, just to prove that the things would start without a roller like so many used. Plus the legends liked to just jump on board and go, without drama, or worry about their ride not starting.
 
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Yep, like Carl and a few others have said, it could just be a kick away from lighting up. I've not personally owned a Norton that was particularly easy to kick over. I'm not real tall, so I like to get pretty damn violent with the kick starter. If your not 6'-8" 265lbs and the motor is really easy to kick over, I would tend to think something was wrong with the compression, head gasket leak between cylinders, burnt valves, worn out seats, yadda yadda. I don't know nothing though... just guessing and making noise.
 
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In the final analysis if he kicks it over easy pezy with NO plugs, what does body size and strength have to do with it?
If it doesn't spark in open air?
How do you think it will fire up under pressure?
HELLO any body home? LOL

Test the boyer box in the triumph I assume it runs? hopefully
 
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The T140 was running but the oil switch light started flickering so I was waiting for a friend to send me a pressure gauge from the UK to test the oil pressure. But I guess I can fire it up a few seconds just to test it the Boyer. I already removed it but gonna require some new connectors. I will try and see if I can find them tomorrow but here we are in lockdown so only some shops are open.
It's a bumpy road being a self-learning wannabe mechanic because without a mentor or means to make comparison makes it harder to evolve. Not to mention lack of some adequate tools. That's why for now I am unable to measure compression or strobe the ignition timing.
But I will get there with all your help :)
I will let you guys know as soon as I test it. Thanks
 
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In the final analysis if he kicks it over easy pezy with NO plugs, what does body size and strength have to do with it?
If it doesn't spark in open air?
How do you think it will fire up under pressure?
HELLO any body home? LOL

Test the boyer box in the triumph I assume it runs? hopefully
All engines kick over easy with the plugs out. I'm addressing the OP about starting the engine, which is what this thread was about. I'm certain the motor will never start with the plugs out. LOL

When did the bike in question stop sparking entirely when being kicked over? Weak spark and backfire is still a spark.
 
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All engines kick over easy with the plugs out. I'm addressing the OP about starting the engine, which is what this thread was about. I'm certain the motor will never start with the plugs out. LOL

When did the bike in question stop sparking entirely when being kicked over? Weak spark and backfire is still a spark.
There is a spark but I was in doubt if it should spark every single full engine cycle. I would only see the one spark with a vigorous kick. without the plugs I believe the engine does several full cycles in one kick right?
Long story short started doubting the timing because the bike would only give me backfire or a bang coming from the carb inlet followed by smoke. After discussing and some testing I am about to test the electronic ignition box on another bike to see if it's working properly. Also tested the EI touching the black/white and black/yellow wires and produces a nice big spark
 
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There is a spark but I was in doubt if it should spark every single full engine cycle. I would only see the one spark with a vigorous kick. without the plugs I believe the engine does several full cycles in one kick right?
Long story short started doubting the timing because the bike would only give me backfire or a bang coming from the carb inlet followed by smoke. After discussing and some testing I am about to test the electronic ignition box on another bike to see if it's working properly. Also tested the EI touching the black/white and black/yellow wires and produces a nice big spark
did you try a few kicks with the trigger leads reversed?

from post#40
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
 
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Does your aternator rotor have 2 pads with timing marks?
If it has 2?
are you using the pad/mark opposite the crankshaft keyway and PAINT/color it? so not to confuse and pick wrong mark??

Could some one have put an atlas crankshaft? They are not the same keyway timing as commando
 

L.A.B.

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Does your aternator rotor have 2 pads with timing marks?

Post#5
Are there two timing marks on the alternator rotor (as a '69 rotor could still have only one)? If there are two rotor marks 180 degrees apart then a common mistake is to set the timing to the wrong mark so the sparks will occur 180 degrees out.

Post#30
Yes it's seems to be the later one with two marks 180 degrees apart.
 
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I'm going to test my logic in the sentence below. The rest of my post is just delusional old guy talk. The prosecution may want it all stricken from the record.

Test sentence: If the motor is at TDC compression stroke for the cylinder on the timing side (right) and the mark on the rotor lines up with the TDC mark on the timing degree indicator tab, nothing is unique about the motor in the bike.

Close to off topic: If you don't have the timing degree indicator setup on the primary side, you might need a degree wheel and a piston stop or piston position indicator that screws into the spark plug hole to get things where they should be in order to set static timing. In the olden days I did static magneto points timing with a piston position indicator like below. Cave man stuff

IMG_6064s.jpg


Horse poop starts here:

If the mechanically inclined out there want a reasonably simple challenge, time a P11 for a Boyer ignition. The stator is mounted to the primary outer cover with no inspection hole and no helpful timing degree indicator anywhere. All you get are the marks on the alternator rotor (if you have a later rotor), which you can't see. Timing a Commando should take about 15 minutes. Timing a P11 takes some ingenuity. All the technobabble and overthinking in the world wont get it done.

I have an Atlas (P11) engine with a 2S cam in it. Yes it can be done. Nothing is different about setting up the timing from how it is done on a Commando except for the ingenuity part of figuring out how to do it. Point being, the keyway on the crank for the alternator rotor was not an insurmountable obstacle in my case. I have 2 timing pads on the rotor. I used a degree wheel and somehow figured out where to put the mark on the stator. It was a long time ago, and I actually don't remember how I did it. Probably took the primary cover off, mounted the degree wheel to the rotor, got the engine to 32 degrees BTDC, took the degree wheel off, removed the stator, guesstimated where to put that hole in the outer primary and drilled it, remounted the stator, remounted the outer primary cover, and marked the stator. Then took the outer primary off, removed the stator filed a line in the resin where I made the mark, then painted the mark, remounted the stator, and remounted the outer primary cover. When the marks on the rotor and stator are lined up, the timing is at close to 32 degrees advanced. The marks are wider than 1 degree, but it's all close enough to check timing. I've only strobed the motor once with the Boyer MkIII. I timed the Boyer MkIV without strobing it.

IMG_5955s.jpg


Hole plugged.
560A0887cs.jpg


How does this help the Migsan? Doesn't

Migsan you don't need to respond to the above babble. It's writing therapy.
 

Carl H

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I'm going to test my logic in the sentence below. The rest of my post is just delusional old guy talk. The prosecution may want it all stricken from the record.

Test sentence: If the motor is at TDC compression stroke for the cylinder on the timing side (right) and the mark on the rotor lines up with the TDC mark on the timing degree indicator tab, nothing is unique about the motor in the bike.

Close to off topic: If you don't have the timing degree indicator setup on the primary side, you might need a degree wheel and a piston stop or piston position indicator that screws into the spark plug hole to get things where they should be in order to set static timing. In the olden days I did static magneto points timing with a piston position indicator like below. Cave man stuff

IMG_6064s.jpg


Horse poop starts here:

If the mechanically inclined out there want a reasonably simple challenge, time a P11 for a Boyer ignition. The stator is mounted to the primary outer cover with no inspection hole and no helpful timing degree indicator anywhere. All you get are the marks on the alternator rotor (if you have a later rotor), which you can't see. Timing a Commando should take about 15 minutes. Timing a P11 takes some ingenuity. All the technobabble and overthinking in the world wont get it done.

I have an Atlas (P11) engine with a 2S cam in it. Yes it can be done. Nothing is different about setting up the timing from how it is done on a Commando except for the ingenuity part of figuring out how to do it. Point being, the keyway on the crank for the alternator rotor was not an insurmountable obstacle in my case. I have 2 timing pads on the rotor. I used a degree wheel and somehow figured out where to put the mark on the stator. It was a long time ago, and I actually don't remember how I did it. Probably took the primary cover off, mounted the degree wheel to the rotor, got the engine to 32 degrees BTDC, took the degree wheel off, removed the stator, guesstimated where to put that hole in the outer primary and drilled it, remounted the stator, remounted the outer primary cover, and marked the stator. Then took the outer primary off, removed the stator filed a line in the resin where I made the mark, then painted the mark, remounted the stator, and remounted the outer primary cover. When the marks on the rotor and stator are lined up, the timing is at close to 32 degrees advanced. The marks are wider than 1 degree, but it's all close enough to check timing. I've only strobed the motor once with the Boyer MkIII. I timed the Boyer MkIV without strobing it.

IMG_5955s.jpg


Hole plugged.
560A0887cs.jpg


How does this help the Migsan? Doesn't

Migsan you don't need to respond to the above babble. It's writing therapy.
One thing that could be a fly in the ointment, (Some thing that could be a problem:) The alternator rotor outer is broken away from the center, so the timing marks are not in the proper position. This is more common on Triumphs, not so much on Nortons.

I dug out my Combat work records as I was setting the cam timing with a degree wheel and also checked the 28 and 30 degree BTDC of the pistons.. So,, 28 degrees BTDC on the degree wheel Or the Norton timing plate= piston is .270" BTDC,

at 30 degrees BTDC piston is .305" BTDC on the compression stroke .

Simply put: get the piston at top dead center on the compression stroke , then back the piston down ( turn the engine backwards) to get the piston lower by .305" and the alternator rotor mark should be at 30 degrees on the clutch cover timing tag. Or very close to it.

IF you use those numbers, that will help confirm if the rotor marks when lined up with the timing degree plate line up properly, Give or take a little.

In the old days with Triumphs , I had a small screw driver with marks on it for TDC and 38 degrees before TDC. It was close enough for me and saved time.
 
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