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maylar, any luck with your misfire issue?
Phil
Phil
Misfire at idle
- Thread starter maylar
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maylar
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Update -
The only items external to the engine that I hadn't consiously replaced or swapped are the intake manifolds. I did that a few days ago, expecting that either a) there'd be no change, or b) problem would change sides. Instead, the misfire seems to have gone away!
Only thing I can figure is that I replaced the o-rings between carbs and manifolds instead of reusing them. I always suppliment them with a smear of RTV so it never occured to me to replace them. I've only taken short rides since (it's been too HOT), and need to put my ColorTune on it to be sure but it seems to be cured. Will report back after I give her a good test.
The only items external to the engine that I hadn't consiously replaced or swapped are the intake manifolds. I did that a few days ago, expecting that either a) there'd be no change, or b) problem would change sides. Instead, the misfire seems to have gone away!
Only thing I can figure is that I replaced the o-rings between carbs and manifolds instead of reusing them. I always suppliment them with a smear of RTV so it never occured to me to replace them. I've only taken short rides since (it's been too HOT), and need to put my ColorTune on it to be sure but it seems to be cured. Will report back after I give her a good test.
batrider
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Thanks for reporting back - Another good gem to tuck away.
I thought the propane trick sounded good so I tried it. I had a propane torch handy and went around the manifolds with it to see if it would affect the idle. I noticed that if the metal nozzle of the propane torch touched the bike there was a spark. This is not good. I think the propane rushing through the nozzle was building up an electrostatic charge on the nozzle which was then discharging to the bike. Might be good to attach a ground wire between the propane nozzle and the bike.
Russ
I thought the propane trick sounded good so I tried it. I had a propane torch handy and went around the manifolds with it to see if it would affect the idle. I noticed that if the metal nozzle of the propane torch touched the bike there was a spark. This is not good. I think the propane rushing through the nozzle was building up an electrostatic charge on the nozzle which was then discharging to the bike. Might be good to attach a ground wire between the propane nozzle and the bike.
Russ
Onder
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Often times the simplest problem is correct. Id not use rtv as it
is reduced easily by fuel.
Vac leaks often bother at idle but not farther up the rev range.
As for the grounding, you should have been on the engineering staff on
the Hindenburg!
is reduced easily by fuel.
Vac leaks often bother at idle but not farther up the rev range.
As for the grounding, you should have been on the engineering staff on
the Hindenburg!
MikeG
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Maylar-Glad you sussed this one out, I've been following the thread with intrest as I had a similar problem on my 71 Commando. Misfire at idle and abrupt power hit right off idle. This had me chasing carburation gremlins for a week. Finally pulled every spade type electrical connector off the coils, condensors, and resistor. Cleaned each one and squeezed it with pliers to tighten it up. Problem GONE. It's the simple things that get you in the end.
MikeG
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