Ok Wth No One Will Spaek Up

[bajagunny]

WELL I WAS GONNA UP THE JET ON THIS 350X TO A 145 BUT WHEN I TOOK THE OLD ONE OUT IT WAS ALREADY A145
SO THAT MEANS THAT THE BIKE WAS RUNNING A STOCK(PROBABLY GUTTED0 PIPE AND 145 MAIN WITH AIR BOS COVER ON
RAN OK BUT I ADDED THE PIPE AND A TWIST THROTTLE STAYED WITH THE 145 AND CUT A HOLE IN THE TOP OF THE AIR BOX ABOUT 2 1/2 X 4 SEEMS TO RUN OK LOTS MORE POWER AND WHEELIES IN ALL SIX GEARS
NOW THE QUESTION IS SINCE IT WAS ALREADY JETTED AT 145 SHOULD I GO UP A FEW TO SEE IF I CAN GET EVEN MORE OR ???
ALSO IF I RAP IT OUT IT BACKFIRES WHEN I LET OFF THE THROTTLE
?? ANY TIPS
THAKS

[ATCnut]

Stock 350X main jet is a 138. Take the trike out, get it warm, and make a high speed run. Shut it down, and coast to a stop. Take the plug out and see what it looks like. If it is black, then the jet is too big. If it is white, then the jet is too small. If it is tan, then the jet is just right. You actually get more power running a small jet, because the motor leans out. The problem is heat, the motor will burn up. Therefore the most power is obtained by running the correct jet.

[Mr. Richard]

if you are freeflowing more exahust i would go up a size or two,,,

backfires are caused by leaking exahust,,its getting oxygen sucked in somewhere ,,,,