Norton Commando 1969 timing issues

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Yes, so I don't know why DD mentioned "blue Boyer box"?
T140 boyer was our PM discussion... blue was an unfortunate misinterpretation as I knew also it was a mk4(analog) though you only partially quoted ME

Wire the black box directly to your charged battery, bypass the bikes electrical system and try it
Put your volt meter on the BOYER power lead wire connection not the battery and or wire direct....as per seeley920

2-3 kicks and you will know if it works
 

L.A.B.

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T140 boyer was our PM discussion... blue was an unfortunate misinterpretation as I knew also it was a mk4(analog) though you only partially quoted ME

Well, if you only post half the story on the public forum then it's to be expected, unfortunately.
(The reference to blue boyer box where there isn't one is still mystifying!)
 
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To make a spark you absolutely must have a high enough current to make a magnetic field in the coil. The rapid collapse of that magnetism is what makes the spark. That current must come from the battery as a bad powered or grounded blue cap would not be expected to make high enough current long enough to build a magnetic field to then be interrupted by a ignition box for the fields collapse.
 

DogT

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Personally I think the OP is fighting a weak spark. I'd do like suggested, hot wire the ingition with your own setup. Bypass all the bikes old wiring. And there's nothing wrong with using a car battery and jumper cables or a good charger connected to the battery. It's just a bit hard having someone run alongside the bike holding the car battery. If it's hard to push over compression, it's likely good.
 

concours

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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
The fact that the OP has spent days trying to get an engine started tells us that he's not an accomplished mechanic. (NO disrespect) We've all seen & read it before: "Turns out it was XXXX all along!"
The fact that the thread is obsessing over precise timing being the cause of no-start is telling. It'll usually start & run (poorly) advanced or retarded.
Suggesting starting fluid to confirm/rule out a viable combustible mixture is a quick acid test I have used with great success for decades.
My mantra of "test, don't guess" stands.
99DC97F9-9502-418D-B8FB-B3AE7D82BBEF.jpeg
 

Carl H

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The the old days, My brothers used to have me be the spark tester, They had me hold the spark plug wire or coil wire when the spun the engine over. If I jumped a mile, they knew they had spark. I was young and dumb! The alternative is try to bump start the bike with a strong young person to two to push it, perferably down a hill. and using 2nd or a higher gear to spin the engine over faster than a kick can do. Then you can try different throttle setting as it is being spun over. Desperate times need desperate measures.
 
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Here's some more peanut gallery noise:

Isn't a test a guess if what is being tested isn't the problem? :)

If the timing was not set up bass ackwards (ATDC instead of BTDC), it sure seems possible, as was suggested very early on in this thread, that the cam timing is wrong. This bike hasn't run right for a long time. Could be a clue regarding the cam timing. Cam could also be one of the early mythical 2S soft cams and went flat log ago. Guesses obviously.

Dave brought up the compression test. Was that ever done?

Something to check for the heck of it. The Reg/Rect could be bad. In that case, the ignition would have to rely entirely on the battery output. The static or kick over spark tests would be successful with a dead reg/rect and a close to 12V battery. The reg/rect and the stator are real easy to check. Might not make a bit of difference getting the bike started, but worth testing, because the motor would run longer after it did start if the stator and reg/rect is working.

Personally, if I couldn't resolve this in a couple of hours of continuity testing, carburetion examination, and most of what has been brought up here, I'd have that timing cover off to see what the heck was going on inside. Regardless of how much people dislike the Boyer ignition box, it usually isn't the problem. I don't know nothing. I'm just making noise.

Edit: The valves were adjusted right? I can't remember.
 
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Here's a thought.
The original poster replied to Seeley920's question regarding the location of the points as being in the timing cover, not behind the barrel. His engine is newer than a '69!
If the Boyer is made for a '69, the rotor will be turning the wrong way if installed in the later style engine.
 

L.A.B.

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The original poster replied to Seeley920's question regarding the location of the points as being in the timing cover, not behind the barrel. His engine is newer than a '69!

It's an 'S' type, therefore, the engine is 20M3S with camshaft points housing so March 1969-on (from eng. 131257).

If the Boyer is made for a '69, the rotor will be turning the wrong way if installed in the later style engine.

The Boyer suits both 20M3 and 20M3S so can be set for either rotation.
 
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If the Boyer is made for a '69, the rotor will be turning the wrong way if installed in the later style engine.
FWIW the boyer is not sensitive to direction. Only by placing the rotor mechanically in the correct position (cw or ccw) relative to the pickup coil appropriate to forward rotation of the drive.
 
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Boyer box needs
+ from red battery ground direct if necessary
- 12v power from battery direct from battery if necessary

NEVER-ever let a coil fire unless plug or High Voltage wire is grounded.
Engine must be wired to red harness ground that goes to battery ground for spark return or it will eventually or already has killed the box.
 
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So after testing the spark through and through I can say I have a spark at every kick but has to be a vigorous one. maybe that's how it should be. The wiring on the bike is all new. The white wire is connected to the ignition switch and and I have a negative from the battery directly to the switch. Everything seems to work has it should with the ignition switch so I placed the spark plugs back in and primed both carbs. Gave it a couple of kicks with the ignition off and afterwards turn it on. I get a bang from the pipes like backfire at first kick. If I continue kicking I get smoke from the carbs intake hole and a bang.
I checked the timing over and over again and I don't see where I could got it wrong. Before all this I set the valve clearances as well.
The spark is doing it's job igniting the fuel right? so if I have smoke coming out of the carbs with a bang wont it mean the I am getting spark while the intake valves are open? how could this be?
Should I check the cams to be sure?
Thank you all for the help!
 
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Boyer box needs
+ from red battery ground direct if necessary
- 12v power from battery direct from battery if necessary

NEVER-ever let a coil fire unless plug or High Voltage wire is grounded.
Engine must be wired to red harness ground that goes to battery ground for spark return or it will eventually or already has killed the box.
I have positive wire running continuously from the batery to the frame - engine head - positive side of the coil where the red wire from the boyer ignition is connected
 

concours

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"Isn't a test a guess if what is being tested isn't the problem? :)"

Nope.
A test will either rule out or confirm functionality of something. From which the troubleshooter can make an informed decision where to keep testing. Goes rather swiftly, actually.

A test, when performed by a layman, can sometimes report inaccurate results. For instance, if a person is afraid to firmly grip a sparkplug and hold it against the ground, the spark test is sometimes inaccurate. Because the tester is afraid of electrickery.
 

concours

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So after testing the spark through and through I can say I have a spark at every kick but has to be a vigorous one. maybe that's how it should be. The wiring on the bike is all new. The white wire is connected to the ignition switch and and I have a negative from the battery directly to the switch. Everything seems to work has it should with the ignition switch so I placed the spark plugs back in and primed both carbs. Gave it a couple of kicks with the ignition off and afterwards turn it on. I get a bang from the pipes like backfire at first kick. If I continue kicking I get smoke from the carbs intake hole and a bang.
I checked the timing over and over again and I don't see where I could got it wrong. Before all this I set the valve clearances as well.
The spark is doing it's job igniting the fuel right? so if I have smoke coming out of the carbs with a bang wont it mean the I am getting spark while the intake valves are open? how could this be?
Should I check the cams to be sure?
Thank you all for the help!
Remove the spark plugs, put a teaspoon of gasoline in each hole, replace the plugs. Kickstart & report back.
 
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The fact that the OP has spent days trying to get an engine started tells us that he's not an accomplished mechanic. (NO disrespect) We've all seen & read it before: "Turns out it was XXXX all along!"
The fact that the thread is obsessing over precise timing being the cause of no-start is telling. It'll usually start & run (poorly) advanced or retarded.
Suggesting starting fluid to confirm/rule out a viable combustible mixture is a quick acid test I have used with great success for decades.
My mantra of "test, don't guess" stan

Remove the spark plugs, put a teaspoon of gasoline in each hole, replace the plugs. Kickstart & report back.

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!
 
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I'd suggest trying to verify "test, don't guess" a spark every time you kick !
rather than
assume the ignition is OK (sounds like an ignition problem to me) and hope it will run

Does your triumph run? put the norton boyer box in the T140? "test, don't guess"
 
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I'd suggest trying to verify "test, don't guess" a spark every time you kick !
rather than
assume the ignition is OK (sounds like an ignition problem to me) and hope it will run

Does your triumph run? put the norton boyer box in the T140? "test, don't guess"
Yes I can try that and report back. Thanks :)
 
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