bk mod

3 replies to this topic
  • Guest_mxrider426_*

Posted May 22, 2002 - 02:16 PM


Does the bk mod do anything if your bike doesnt bog off bottom? Motoman seems to say it will give you better throttle response.

  • John_Lorenz

Posted May 22, 2002 - 03:36 PM


I believe motoman

I had the Bog of bottom, after the BK the bog went away.

After tweaking and fine tuning the BK the throttle responce was very noticable.

The bike snaps like a 2smoker out of the burms...
It hustles very rapidly now

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  • Mark_Cantrell

Posted May 22, 2002 - 05:45 PM



If you have more gas delivered by the AP than is required to keep you bike from cutting out or dying the way you ride it, the additional fuel (volume or duration) will make your bike more sluggish.

That being said, you may not have too much fuel being delivered by the AP. If not, the BK mod won't help. Many with the BK mod tend to cut the squirt way short. If you do the BK mod, use your common sense and experience instead of the .3s that worked for Ferry.

Good luck,

  • skthom2320

Posted May 22, 2002 - 05:53 PM


I am not convinced that every bike needs it, especially the '01 and newer.

I have not done the mod and I am completely satisfied with my throttle response at the track. I do pay attention to jetting however and keep things on the lean side, especially on the pilot jet. Just a bit of popping on deceleration seems to deliver the snappiest low end response.

Careful jetting is the key.

I think there is no question that the '00 and earlier bikes benefit from limiting the AP pump stroke.

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