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New Slip On And Jetting = Backfire?

849 Views 5 Replies 3 Participants Last post by  sidewinder
i recently got an hmf sport series slip on and when i put it on i rejetted the carb to the recommended specs on the hmf website. i went form a 42 pilot to a 48 and from a 155 main to a 170...i didnt mess with the needle or clip or fuel screw just because i was told i probly wouldnt have to and because im fairly new to my bike. i have a stock filter with the lid off and no other mods other than what i have just done to it. can anyone point me in the right direction?

thanks in advance
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Your too lean if it backfires or pops.
QUOTE (Sidewinder @ Mar 16 2009, 06:12 PM) index.php?act=findpost&pid=758501
Where in the throttle range is it popping?[/b]

usually it will pop when its idling and i punch the throttle and also when i rev the thing about half throttle....too lean? should i go to a 175MJ maybe?
so i got up this morning and went out and threw in a 175 main jet and it seemed to get rid of alot of the popping. i havent been able to ride since i did this but it seems alot smoother....
I would also throw in a bigger pilot. That'll help with the idling issues.
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