1937. 115C clutch

Posted by David rose On 2015/12/20 9:00:08

Replacing the clutch in my 1937 115 C. I received a new disc from a vendor on line . The disc I received has a smooth riveted liner on it, all the clutch disc I have seen have groves in the riveted lining. I think this is for a ECONO - drive.? Should I use this? My order stated 1937 115 C. Six. Why are thair groves in the disc for ? Thank you. Dave