still won't start

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GavinJuice

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Jul 24, 2007
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still got this commando that will not insist on running. i got fuel spark compression but it will not run. i can tickle it and get a few flames out the back but just smoke afterwards. i know it's timed right which was the issue from the get go, i just can't think of anything i'm missing. is it possible i'm not getting any more fuel once that initial tickle? tried choking it and not chokeing it with no avail.

anything info would be greatly appreciated. OR is there anyone in MN twin cities that would be willing to take a look?? Thanks ~Gavin
 
Explain in detail how you time the bike. Include info like Points-Boyer coil type and how there wired. Do a compression test with the plugs out and the throttle wide open five or so kicks Lbs both sides.
 
i've set each cylinder on compression using the thumb method @28 on the primary. with the AAU advanced each side individually set just opening using a bulb. stock points stock coils BPR7ES plugs both new AND i have carbon wires which ive been told should not be a problem. i know you (norbsa) said you've run them for years.

ive performed a compression test dry with 135 and 150 throttle wide open through a complete power phase.

one thing that has me confused is when i have ignition on, switch to run, i cannot get a spark when i spin the engine over in fourth. i see the point open and close and no spark on the plug when grounded?? if i crank it with the electric start i get a nice fat spark but not when i spin it over by hand. I was trying to confirm i WAS getting a spark when i hit that 28 degrees statically.

Is there anything in the carb that could be preventing it from pulling in any fuel? It makes me think i only get a ignition when i tickle it cause i see them overflow and fuel flow down the intake.
 
I ran Accell wires for about six months till I discovered that the carbon core wires can't take the vibration. I have run nothing but copper stained wire on all my bikes since so you have me mixed up with someone.
With a point system, a plug in it's wire, grounded to the head, you should with the key on and the points closed be able to get a spark each time you force the points open with a thumb nail.
You could be having carb problems but if your timed close and you tickle the carbs it should fire and run just a short time.
You do have a known good ground to the head?All the way back to the battery positive?
You have run a continuity check on your points wires ?
Plug gap for points is .025 you have checked that?
Can you by flooding the carbs, plugs installed kick over the bike and make the plugs wet?
 
yea i replaced all my battery wires 6awg and all resistance is good. i should mention i setup the carbs with the idle air screw 1.5 out and the throttle stop to where it was before. i see i should have both at 1.5 to 2 turns in according to AMR.

plugs are gapped .025 and yes still wet so i guess that answers my question.

these thing's aren't complicated at all but man this thing is throwing me though a loop.
 
Your battery wires can be brand new, but if you don't have a known good ground to the head with wire leading back to the common ground the spark will not be strong enough under the pressure of compression. There should be a bunch of red wire in your harness the ones that hook to the head brake often. Not having a common ground that that ties all the red wires to the positive of the battery can cause grief, with an e-start they put a good one near the starter body but were do the red wires in the main harness tie to the ground on the battery? Check this out. I add grounds to many key pieces in the system it's the over looked part ,the one Norton saved a penny on that will get you every time.
 
yea i took a 10awg wire from the headsteady and soldered it into the harness where about 4 red wires all connected at a common point. that wire was origionally going directly to the battery, the common point, and then to the headsteady. I guess i'll take some voltage readings and see is i get any drops.
 
ok so i'm out there again, crank it over get a couple pops pull the plugs out and they're wet and look relatively clean. a little bit of soot, but nothing like a clean burn. leads me to think i'm getting either a weak or intermittent spark under compression.
 
ok one more for the night. i've got the points cover off and watching the points while i crank it over, i get a yellow spark (more like arc) across the yellow/black set of points every once in a while and a noticeable snap sound when the spark occurs. hmmm..... The black/white point is good with just a small blue spark on open and close, barely noticible. I remember reading a bad ballast will give a good fat arc when they open but then it would happen on both sides. That would rule that out. Both points are new and gapped .015. I can't give up, i'm so close!!
 
GavinJuice said:
i've got the points cover off and watching the points while i crank it over, i get a yellow spark (more like arc) across the yellow/black set of points every once in a while and a noticeable snap sound when the spark occurs.
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Could be a faulty or badly grounded/connected ignition condenser?

Try swapping the condenser wires over, to see if the arcing then occurs on the other set of points.
 
Make sure the condensers (capacitors) are good and in the circuit. Missing or faulty condensers will cause most of the spark energy to be dissipated when the contact points open and burn them out rapidly.
 
Back in olden times (when I ran a points ignition) I found that many of the aftermarket condensers would short out. If you have changed condensers, try putting the originals back in. If you don't still have them, carefully check that these cannot short to the mount.
 
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