New to Thumper Talk...

I just bought an '02 WR426F and I am interested in learning more abouth the free mods. When uncorking the pipe, do I need to rejet?

Any advise on how to get the most out of my new bike would be appreciated.


try the search button and type in free mods

You will not need to rejet with the pipe core pulled. Pull the cover off your air box you dont need or want it, except when washing it or transporting/trailering it in heavy rain, keep that filter dry.

Check the bottom of the main index for archives, things you will want to look for, throttle stop mod, this is a must as the throttle is only opening 1/4. You can unscrew the stop and cut it to length with dremeltool / hack saw, look in the archives for the correct length These 3 mods will get the bike back to normal, running as it was intended to. Other mods include yz timing, bk mod, grey wire(debatable whether it does anything) And rejetting with a new pipe.

I would do the first 3 mods, get used to the bike and tweak on it later when you have the bike figured out.

Good luck

Welcome to TT! Take your coat off and stay for a while. Definately checkout our "search" feature. Also, go to and look for the motoman393/TT site. Tons of great info for you there. Cheers!


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