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engine misfire

nascar7613

Active Member
02 night train, carb, engine will misfire at midrange rpms when trying to accelerate ,two or three misfires then clears out. any ideas?
 
this has been going on for a while. it has been taken to the harley dealer and they changed the jets in the carb, so I assume the bowl should be clean
 
Very true but as you can tell, I don't trust the dealers and have good reasons.

I could be water in the tank also that draining the bowl will give you temp relief to diagnose it.
 
so it sounds like a fuel problem to you. It feels like a spark plug or plug wire breaking down, but both have been changed and the problem persists. the bike was put on a dyno and the air fuel seemed to be rich, running below 12:1 everywhere. could that be the problem?
 
so it sounds like a fuel problem to you. It feels like a spark plug or plug wire breaking down, but both have been changed and the problem persists. the bike was put on a dyno and the air fuel seemed to be rich, running below 12:1 everywhere. could that be the problem?

Without knowing till now that the wires and plugs were changed, I would approach the fuel by draining the bowl and see if it makes a difference. Try to catch the draining fuel in a glass to let it settle and see if you can visualize any water in the bottom of the glass. The drain comes out in front of the rear wheel.

A rich mixture will usually only show as poor MPG and a poor response from the throttle but rarely show as you are experiencing unless it is fouling a plug. Check the gap recently on the new plugs?
 
Are you looking from the opposite side of the bike than the carb and between the cylinders at the back of the carb?
 
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