ATV Florida Forum

General => Tech Corner => Topic started by: BIGBUB911 on November 06, 2008, 08:38:26 PM



Title: 2002 400ex jetting carb?????????????? help please!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Post by: BIGBUB911 on November 06, 2008, 08:38:26 PM
i have a 2002 400ex with a white bros. pipe k&n filter and k&n air box lid
and wanted to know how and what jett to use it came with a 168 and 170 jet
i put the 170 in but it dont seem wright and it does not help that i dont know anything about
adjusting the carb an anyone help me >:( >:( >:( >:(


Title: Re: 2002 400ex jetting carb?????????????? help please!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Post by: quadguy33 on November 06, 2008, 08:50:55 PM
need more info. what is the bike doing. not idleing, back fireing, cuting out. is the pipe a slip on or full.


Title: Re: 2002 400ex jetting carb?????????????? help please!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Post by: BIGBUB911 on November 06, 2008, 09:00:02 PM
it is hard to start and it is snapping and popping and it is a slip on


Title: Re: 2002 400ex jetting carb?????????????? help please!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Post by: BIGBUB911 on November 10, 2008, 09:02:49 AM
still need help please >:( >:( >:( >:( >:(


Title: Re: 2002 400ex jetting carb?????????????? help please!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Post by: TRX450R_Racer on November 10, 2008, 09:18:13 AM
I would contact White Brothers and ask them for their recommended starting point.


Title: Re: 2002 400ex jetting carb?????????????? help please!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Post by: 4fittyr on November 10, 2008, 10:17:25 AM
play with air/fuel screw  usually honda"s are 1 1/2 turns out  try that


Title: Re: 2002 400ex jetting carb?????????????? help please!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Post by: scrimmy on November 12, 2008, 05:45:57 PM
it is hard to start and it is snapping and popping and it is a slip on

i think you need to go up a pilot jet and try 2 turns out on the air/fuel screw. is it popping while trying to start or in the upper rpm range? did you lower your needle one clip to richen the mid range up? if you need a pilot jet let me know and i can order you one.


Title: Re: 2002 400ex jetting carb?????????????? help please!!!!!!!!!!!!!!!!!!!!!!!!!!!
Post by: Chevy1500z71 on November 12, 2008, 06:33:06 PM
need beter info. where does it pop, does it pop at wide open, or is it popping and sputtering at low rpms? is the throttle response bad? high idle? low idle? could be the needle or the pilot jet, don't just asume the main jet is your problem, the main jet is for one thing, wide open throttle fuel. the needle adjust how much of the mainjet you are using throughout the midrange, and the pilot jet is low throttle to idle range. moving the needle clip up makes the midrange leaner, moving it down makes it richer. popping normally means lean. hope that helps a little bit.


Title: Re: 2002 400ex jetting carb?????????????? help please!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Post by: scrimmy on November 12, 2008, 09:14:41 PM
what we said