Installed 08 450F Carb on '99 400F...

4 replies to this topic
  • Coonass400

Posted March 30, 2010 - 07:06 PM


Thanks SXP and Grayracer for the help. I installed the 08 carb on my 99 400 and she hasn't run this good since I owned her. No more hanging idle and no more popping after countless attempts at cleaning/setting/jetting, etc. to the old carb. That said, the bike still has a bog when wacking the throttle open quickly but that seems like a common problem still to alot of bikes. Any ideas to better this situation. I've searched a little on the subject but haven't really dug into it yet. Thanks again everybody:thumbsup:

  • JandJ07

Posted March 30, 2010 - 07:11 PM


Its normal. You will never notice it during normal riding conditions. :thumbsup:

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  • tek_01

Posted March 31, 2010 - 02:39 PM


Stiffer accelerator pump spring like the on from merge racing? although i think the 08s have a fairly stiff spring already.
Also if you do get the spring there is also a procedure on how to set the AP squirt timing.
I done this on mine (05) and it helped a lot to the point i cant notice it.

  • Family Man

Posted March 31, 2010 - 09:07 PM


Do a search for the oring mod.

  • grayracer513

Posted March 31, 2010 - 10:53 PM


Stiffer accelerator pump spring like the on from merge racing?

Do a search for the oring mod.

Neither of these, IMO, is necessary. They are, of course both the same thing, except that one uses a real carb part, and the other is a rubber band job.

If the carb is tuned and jetted right, including the previously mentioned pump timing, and you teach yourself the simple reflex of rolling the throttle open instead of snapping it, the engine will never actually bog while you ride it.

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