Coop's Off-Road Performance

Best Bang for your Buck Clutch Mod's
Custom head modifications for two stroke dirt bikes!


     Off-Road Performance
         Clutch Mods & Head Milling 
Yamaha, Honda, kawasaki, Suzuki, KTM, Husquvarna, Beta...
And many more Two Strokes Heads!

              21cc after head milling and dome modification            Finished Mod#3          

YZ250 / 250X Lower Air Box plug for water crossings. Just pop it in when crossing water / streams and just pop it out when done!



I am the originator of the machined sheave Mod#3 and Cam plate Mod#2 and the original 2mm shim Mod#1


I am only doing the mod's on a case by case bases, so please e-mail me before you send your Clutches.
And have a great Day

Clearing the air on my Mods  Once and for all!

This video is me running my Mod#4, it has the maximum lowest ratio, and the tallest ratio for top speed in High and Low range with out rubbing the primary support cage! 
This Mod was only done to set things straight!

Mod#3 is all that is needed!

 Coops ATV & UTV Clutch Mod's 

  "For the best bottom end"

"Up to 30% lower ratio, with no top speed loss!"

Want more bottom end and top speed or both out of your Suzuki Kingquad, Vinson, or Eiger?

Or how about your Yamaha Rhino or Grizzly or even your Kodiak.

No mod to the secondary is needed with Coop Mods and you get the lowest ratio possible, and the highest top speed ratio possible if you want it!  "And all by modifing only the outer primary moveable sheave!"

It really is just that simple with Coop's Clutch Mods!

The Video that started it all!