STUTTER/BOG AT 1/4 THROTTLE

[Flynbyu]

Did you change the plug after you re-jetted or is that the original plug before your rejet?

The true and correct way to make 100% sure you're not too lean is install a new plug after a rejet. After the install, get it up to speed, ride for a couple of minutes, kill the bike. Pull the plug, then read.

If the plug was black before and now it's white could mean a number of things. You could have burned off excess carbon on the plug, or if you had a change in your climate while riding could affect the plug color too. Usually a white plug will indicate a lean mixture, but it's hard to say on an old plug.

As far as the next step, did you try removing the airbox lid to see if it still bogs at 1/4 throttle?

~Brian

[GRAPTOR]

No, I did not that is kind of tough with the Raptor because the lid hold the filter in place.  I ordered the unifilters and will have them Thursday.  My plan is to install the unifilters,  take my main jet back up to a 155 and leave the pilot at 25 and three turns out on air/mixture.  Does that sound where I need to be or should I try a different approach.

Jon

[Flynbyu]

Have you cranked the mixture back a half turn yet to see if that clears the stumble? If that didn't work, my next step would be
to try running without the lid just to see if the bog goes away. If the lid off clears the stumble in the throttle, then install the filters. Changing the main would be up to you, but this is the main I've used on a previous application. Give that a shot and if it doesn't work, buzz me back.

I think the issue of your bog before with the 155 main is due to lack of air flow.

I would spend a couple of bucks on a new plug too, just to make 100% sure I wasn't too lean.

Just remember, It's better to be rich than lean.

~Brian

[GRAPTOR]

Yes,
I have installed a new plug with every jet change. I think I will try to adjust my air/mixture in 1/2 turn tonight to see if that takes care of the bog I have not done that yet.  Are the unifilters worth the install do you see any increase in performance (any experience with them)

[Flynbyu]

The uni-filters just flow a little better if you decide to leave your lid on. They will help!

~Brian