Roz
Extreme
Maybe intake hanges up at high RPM. Mine ran fine at high speed, ran like crap at idle and low speed. Turned out to be exhaust valves. Just saying after you run through all the fuel and spark possible problems, look at your valves.Hope it turns out to be a minor issue.
Thanks! I will look into that too.
pdiddy
TY 4 Stroke Junkie
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- '11 Apex; '16 Apex XTX; '18 Indy 600 SP;
My .02 - Since you reported the engine seems to be loading up at 8K rpm and you're not loosing a particular cylinder or fouling a plug i'd focus the fuel venting system as an earlier poster suggested. I also doubt its your fuel pump - its supposed to pump like mad at high RPMs - just doing its job. Your floats and needle & seats are supposed to regulate that BUT I think they can be compromized by venting issues. Next time it happens I'd pull the plugs to make sure its not a particular cylinder.
I agree with indy clean your carbs and do it yourself so you know they are clean. Pay special attention to your pilot jets they have to be spotless and be able to see through them. Check to make sure the power jets and main jets are not mixed up. People have posted that as well. Next is change your plugs even if they are new. Clean your coils if they are loose put a few wraps of electrician tape on them where it makes contact with the valve cover and install with some dielectric grease.
