jetting and air box help

KC Gager kc at
Tue Aug 24 18:45:46 PDT 2010

What are u trying to fix other then bad tapper needle valves?

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-----Original Message-----
From: sv650-bounces at [mailto:sv650-bounces at] On
Behalf Of matthew patton
Sent: Tuesday, August 24, 2010 6:17 AM
To: sv650 at
Subject: jetting and airbox help

I finally got the front carb to stop dripping raw fuel down the carb throat.
somehow replacing the float needle and it's brass fitting and the float did
the job. Not sure why but I'll take it.

I've got 17.5 pilots, 150'ish mains (I think) and aftermarket needles (not
dynojet, name escapes me) at clip 4 from top, BMC air filter and Yosh race

I've been trying various things and can't seem to make any decent progress.
What is a good starting point?

How much jetting difference should it make with open airbox vs BMC? 1 needle
clip? 2?

Without the BMC it runs a little stutter at >1/2 throttle and 6000 RPM till
about 7.5K and then it cleans up and seems to pull reasonably strong to 9K.
With the BMC in it gets massively ragged at 6K and anything past 1/8
throttle and never cleans up.

I'm guessing my BMC is clogging up the airflow (I'll clean it again) and I'm
jetted way too rich for the BMC but ???? for open airbox.

Can anyone clue me in?


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