How do you adjust the exc pump????????

3 replies to this topic
  • Guest_Guest_*

Posted October 20, 2000 - 03:19 AM


I was looking at the pump, and to me it seems like it is already starting to push on the dia. as soon as I turn the trottle it is squirting, is this right or wrong.. remember I'm the guy fouling alot of plugs...
99wr 400......

  • Gary_Kessler

Posted October 20, 2000 - 06:08 AM


Lots of threads on this subject. Do a search on "accelerator pump adjustment" and you'll find the information you're looking for.

Especially good thread on accelerator pump adjustment - BEWARE.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • Taffy

Posted October 20, 2000 - 10:28 AM


tee hee!

i saw exc & thought Grrrrrrrrrr!!!!!!
accelerator pump is spelt acc

-nice one!!!

just jestin'


  • Clark_Mason

Posted October 20, 2000 - 07:36 PM


Can't believe

If you are fouling plugs you might try shorteneing the pump stroke. With the adjustment via the "fork" on the back side of the pump actuator arm you can control where the pump starts pumping. You cannot control when it stops without changing the diapharam stop bottoming pin lenght or installing a device like the P-38 lightnening.

If you spread the fork it will cause the pump stroke to be longer pumping in more fuel on each whack of the throttle. If you close the fork the pump will start pumping immediatly but WILL STOP SOONER. This means the shot of fuel is not as long an less fuel enters the engine for each stroke of the pump. This is what you want a shorter stroke and on the 99 it means starting sooner and finishing sooner.

So using a needle nose plier close the gap slighly on the fork and it will cause the stroke of the pump to be shorter. Give it a try you can always bend it back. In general shorter stroke is better if fouling is a problem.



Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.