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Backfiring Question
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Posted by: GEARSMOKER

just did a new wieseco piston, and hot cam stage one cam in my friends 2000 ex. adjusted the valves to spec, and now when you let off the throttle after high revs, it backfires pretty decently. any ideas? thanks guys

Posted by: skyhighatv

was the motor stock before rebuild? did you re jet for mods? open air box?

Posted by: RiderTRX400ex

go bigger on the pilot jet, adjust mixture screw

Posted by: GEARSMOKER

motor was stock, 155 main jet ,with a closed air box. new piston is stock size.

Posted by: nowukno

quote:
Originally posted by RiderTRX400ex
go bigger on the pilot jet, adjust mixture screw

Its usually one of those two.

Posted by: Speedy81304

two things. a backfire is when you flame out the carb. an afterfire is when you flame out the exhaust.

if you back fire or after fire its cam timing. neather are a good sign.

Posted by: 04'400ex'er

You should be running around a 45 pilot with those mods.

Posted by: Honda MaNiAc 01

I was going 5th gear on the road today n let off a bit n it backfired but it never backfires what was with that? just cuz i let off?