Running Issues! Jetting?

[muddymess]

I finished putting my bike together and I got a different carb to run this year so I had to jet it. I did the typical run threw and it seemed to run great and the spark plug was just a slight dark tan.

Now this is where I started having issues. I took it to a race yesterday and it ran great off the line. So great I was able to pull 3rd by the first turn. It stayed running great for a while then I started to hear it idling fast when i let off the gas. Then it started missing and sputtering really bad and it ran like crap. Drove it over to the pit and checked things over and everything looked good. put a different plug in and ran 200 yards and it started spitting and sputtering again.

No idea what im doing wrong. the old plug i took out looked a little dark but not wet or anything.

[Honda 250r 001]

pilot jet is off i would say...

[muddymess]

well i had a 52 in it and it would idle the highest at 3 1/2 turns with the air screw so i put a 50 in it.

[Honda 250r 001]

turn the air screw in to 2 turns MAX. If it wont idle with that many turns... then its the wrong size pilot. But anyway. Im betting that the pilot is lean...

[muddymess]

i have it at 1 1/2 turns now for the 50. i only had it at 3 1/2 because i have a tuning "how to" that told me to keep turning it out to where the idle was the fastest and then if it was more then 2 1/2 use a smaller pilot.

[86 Quad R]

check all of the easy stuff first..... check the float level, for trash ect. do a leak down test to eliminate the possibility of an air leak aswell as a center case gasket leak(i've had em draw in tranny fluid). double check the plug wire aswell as things under the stator cover. :cool:

btw: what you gap the plugs at?

[muddymess]

Originally posted by 86 Quad R

btw: what you gap the plugs at?

i'v never actually messed with the plug gaps. i know its something i should do but iv never had any issues before so i never messed with them.