Hoosier D21 Grind or Not to Grind ?

D21 is a pretty soft compound, I can't imagine it glazing over in regular race conditions.

You guys think there is anything to be gained by grinding one between races ? I'd rather not bother if I don't have to.

Thanks for your comments.

In Fla we had issues with them glazing every time we ran them. We grind EVERY tire before it ever sees the car if at all possable, then every time we can. Grind the fronts across and the rear across and you get a million little edges for traction.

Probably gonna depend on where you race. When the super tires used the D#s for compounds, I ran D21s all the time. They rarely needed it.

Guess I'll just watch them and see what they look like.

Thanks guys.

You don't necessarily need to grind them but don't run a fresh D21 on a slick track. They need to be put through a mild heat cycle (like in hot laps or heat race on a heavy to intermediate track) before they will hold up in the slick. That has been our experience anyway.
Where we run crates, we're only allowed to run D21 or D55. The D55 is way too hard - it just won't get enough heat in a short race. I really wish they would scrap it and give us another compound to run somewhere in the middle like a D35.

@ RacerX10 - maybe instead of hitting them hard with a grinder you could just scuff them with a belt sander with a lower grit paper just to get the "glaze off them? we do this w/ our d55s when we can afford to buy new. seems to make them last longer too.

@ Matt49 - thats crazy that you have such a big gap in tires from the D21 to the D55. crate racing was made to be "cheaper" (yeah i know) and the guys who could afford to buy a new set of D21s every week or so will have a huge advantage over guys like me who buy a set of d55s and run them till they are drag slicks. we run 3-5 hot laps, 8 lap heats and a 25 lap feature here, so with proper care and a good scuffing once in a great while, i can get 8 to 10 races on a set of tires before they look to bad. and hell, come the end of the year when funds a really depleted, i might even run a (not a nice word)(not a nice word)(not a nice word)(not a nice word) near bald tire on the LF

Quote:

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Originally Posted by Matt49

You don't necessarily need to grind them but don't run a fresh D21 on a slick track. They need to be put through a mild heat cycle (like in hot laps or heat race on a heavy to intermediate track) before they will hold up in the slick. That has been our experience anyway.
Where we run crates, we're only allowed to run D21 or D55. The D55 is way too hard - it just won't get enough heat in a short race. I really wish they would scrap it and give us another compound to run somewhere in the middle like a D35.

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My experience there was the same.