How do you "Free Mod" a 2002 WR 426F?

Can someone please direct me to what exactly I need to do to bring my WR426 to life? I don't want it real loud, and don't want to change the CAM. Please help, anyone?

I just finally did my 2000 WR 400 and it was very easy and quick. I just disconnected the grey wire under the tank, removed the air box baffle and I ordered a pipe insert off of e-bay that was only $20. I haven't done the throttle stop mod yet but I plan to next.


Do the grey wire cut like mentioned above. Also here are some essentials. :D

1) BK Mod - adjust fuel squirt in carb, try motoman393's website.

2) Throttle stop - shave off a few millimeters.

3) ACV mod- reverse the diaphram in the ACV.

4) If you haven't removed the baffle in the stock exhaust, nows the time :)

5) Re-jet - my bike came all plugged up and constipated from the dealer. The jetting sucked, the acceleration sucked, the bike ran crappy. I used the "search" feature here at TT to find alot of info. Now my bike is AWESOME :D Remember not to do everything at once...if there's a problem you won't know where to start. These simple mods should bring your 02 to life. Good luck :D

Change your exhaust cam timing to the YZ spec. This will make quite a difference. Different exhaust would be a huge help as well.

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