Taffy, James Dean, ANYBODY

Hope you'll can help me.

I have a 2002 WR426 - grey wire, lid off, bk, power now,uncorked, yz throttle stop, live in Palm Beach (low sea level)- 42 pj, 165 mj, drs 4 clip,pj 1 1/2 turns, the rest is stock.

The bike ran great for 3/4 year. Then it started sputtering - easiest to notice at 1/8 - 1/4 throttle. But seems to do it all the time. Traded carb with a friend and the problem moved to friends bike. So it must be in the carb. Carb cleaned twice by me and once by the pros. No joy. Traded my stock drr needle for a leaner drs needle 4 clip. No joy. Tried an ekp needle - worse. Tried a 38 pj - no joy. It seems to come and go. I took it to Yamaha & it ran ok. They said they didn't think it was worth working on. Brought it home and got it hot - sputtering out the exhauset. One other thing. When it starts sputtering it feels like I sat up and the wind caught me. Not a surge - an unsurge. Like a rubberband pulling me back. email me if you can help jdole@bellsouth.net

Are you sure you have the (BK_MOD) APJ spray timing and duration set right?

Did you change gas or air filter oil?


I had same problem with my 02 it ran great for awhile then popping and sputtering.Recently whent to 155 main and 3 position on needle.3rd from top lowering needle down,and moved my bk mod out (i think my perception of .3-.6 of a second was a little off visualy to quik of squirt)tweaked my kouba to 1.0 turns and now she rips.hope this helps.pm me if you need further assistance. :)

Thanks for your suggestions.

RB - I've changed a lot and it stays the same. I think it might be what sends the signal to the TPS.

I traded the TPS and it ran the same. That's why I think it's what hooks up with the TPS inside.

RB - what was your original MJ, needle?

Obdqr-#4,kouba-t and b-k mod also helped you may want to try them also.original mj was 168.

[ September 23, 2002, 05:56 PM: Message edited by: ratbiker ]

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