Didn't think about this until after it was installed but on the left is the Spec stage 2 Kevlar and on the right is the Spec stage 1 (don't know the material.) Thought the Kevlar felt lighter but didn't think anything of it until I started driving it. My Seat-of-my-pantsometer tells me there is a quicker response in the revs. I'm only in the break in period at the moment and I'm taking it easy but I was wondering if it was just me or would the lighter disc, even if it's just ~3 pounds have an impact on revs. Thanx

 

Faster gains and losses in RPM are related to the total rotational mass of the assembly (including the flywheel, plate and disc). You may see a minor improvement with a lighter disc but most weight reduction occurs relative to use of a lighter flywheel or even an aluminum pressure-plate option. It is much more likely that you are noticing a difference associated with a clutch that is actually holding versus one that is worn out and slipping (even if slippage is minor).