I posted this on the honda forum, pobably should have put it here first. Does anyone know what racers use to cut knobs off the tires to open up the tread pattern? I have seen it on Turf Tamers mostly.

Nope, I heard of that along time ago. Only thing later is to recut your tread to have sharp edges again. Sorry.

They use a hot knife. They are sold by large places like Chapparal, etc.. I have used a router with a plunge bit before. It works great, but sometimes it smokes like doing the world's largest brakestand!!!

If you are asking how to groove turf tamers, the answer is to use a cutting tool that you can get from Sears. I think channel locks makes one.
ERIC

I used a tire groover on my stock car tires when I raced dirt track. You should be able to find one at any shop that supplies/sells race car parts.

Rude Dog

Take them to a shop and get them done 1 mistake of cutting to low and well there goes $60 for a new tire

I have tried razor blades, but that is painful and as stated earlier, very risky. I bought a set of clipper pliers from Harbor Freight. They work ok, but cut a little funny. THe trully quick and perfect thing to use is a calf de-horner. You can buy them at Tractor Supply Company (TSC). They are perfect. THey pop the treads off perfect. Just open them up, set them against the tire, and close them. That is it. Good Luck!