Not a jetting problem after all

Hello again Gentlemen.....

Well, after many hours and many combinations of jetting I'm leaning towards an electrical problem. Let me know if anyone has experienced or tried this. After a long discussion with the guys at my favorite shop, we decided to start trying a new avenue.

Since this problem has been specific to 1/4 to 3/4 throttle positioning where it begins to blubber,cough,and sputter, I've always been believing that I've had a needle adjustment problem. The bike always ran good down low and also when you could get past the mid area up top too.

With the advise of the guys at the shop I unpluged the throttle position sensor on the carb.

After letting the bike warm up completely,The bike ran rather sluggish and with no real bark that we're all used to.After a fifteen minute hard moto on a near-by track, the bike didn't cough or sputter once. I will definately try it one more time for a longer period,because I pretty much had to stop on account of freezing my paws off in the snow and freezing temperatures.I did notice alot of backfiring when I came off the throttle, but for the most part I'm hoping and praying that I finally found the bug.

Luckily enough I have my '99 wr to pluck the throttle sensor off of to get me by for awhile. I guess the real question now is; does the throttle sensor have to be ajusted or does it just bolt right on?



My 98wr400 did almost the same thing. I ended up replacing the needle and seat. My bike sat for approx 9 months while I was getting a divorce and the needle rubber "hardened up" and was seeping just enough to cause a rich condition. After some riding, things would correct themselves and it would be fine until it sat a little while and then the problem would reoccur. (It would take a little riding to clear the plug)

Yes there is an adjustment for the tps. There is a detailed procedure in the owners/service manual. If you do not have this let me know and I will e-mail you the procedure.(

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