02WR426 Serious Mods!

I just got my bike back from a winter in the shop and it flat screams! It was bone stock as of Dec. 03 except for an electrex dot kit. I registered it in Colorado to ride on the street but it is not a Supermoto.

A list of the mods completed by either ThumperRacing or Chesterfield Valley PowerSports here in St. Louis, Missouri.

Complete rebuild by ThumperRacing including a 450 kit, head porting, new intake valves, and PowerNow carb plate.

FMF full titanium exhaust with PowerBomb

Hinson Clutch kit with basket

K&N filter with jet kit 45 pilot 178 main per ThumperRacing

Maxxis dual dot tires, balanced

Magura hydrolic clutch kit

Removed restrictors per yamaha closed course comp. only instructions.

Braking oversize front wave rotor and brake line kit

One Industries graphics kit

trail computer with billet "dashboard"

The total bill, gulp....!!!

$4585.94 parts and labor


But I rode it this am for the first time, 8 miles one way to work on back streets. It is scary fast.

A bit loud but that is fine with me. And I have no arrestor in the muffler as of yet. It stoppies like no bike I have ever ridden. It seems to shift much more smoothly and transfers from off idle to full throttle much more smoothly than before. It also idles along in gear very strong with no throttle input at all where this would easily kill it before. It starts fairly easily but is harder to kick over than before. Over all, I am very glad that I put the money in this bike instead of buying a new 450. Thanks to ThumperTalk for all the build up ideas I got from your old 426 supermotard project. I nearly duplicated it except for the carb, suspension and wheel/tires mods. But I will be hitting the trails as well as the street. Thanks again!!!

Wanna' race? :D:)




Wow, do you ride dirt or is it all street? If it's mostly street you could've bought a nice street bike for that and have twice the performance :)

Just giving crap, sounds like that things purs. Any pics to post?

I ride it mostly on the street. The only limitation off road would be the 50/50 tires. In the summer I ride in Colorado on some pretty serious trails but hit the highway in between them. I will have to swap tires again before I do that.

If you ride mostly street, you ought to try some supermoto wheels. They are really fun on the street. I have some supermoto wheels for when I want to ride around on the street and a little dirt, then the stock wheels for dirt.

Absolutely want some motard wheels! What is another $1G at this point, right?! I am building up my Toyota 4Runner right now though. Having some 404 portal axles built by EXAXT up in Canada so all my money is going into that project for now. Maybe next winter I will strip my WR down to the frame and have it powdercoated and some of the motor to match, then some new wheels, brakes, etc. But I am having waaaaay to much fun to mess with it right now. It is completely dialed in with a super strong mid range hit and just keeps pullin and pullin! Can't wait to get it on some sand dunes this summer.

just checking out my personal info to see what shows up.


You mentioned the TT Supermoto project bike.......

That bike is sitting in my garage in Boulder!

You mentioned the TT Supermoto project bike.......

That bike is sitting in my garage in Boulder!

How'd you happen on that one???

I bought it from Steve Claus, TT owner.

It's a seriously great bike. Had a bit of trouble with it,so now I'm waiting for the motor to come back. Should have it just in time for our first supermoto race here!

What size tires did you end up with?

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