have a question for the experts. I have a 2011 RK and was give an engraved derby cover from a older model here is the question. I noticed the new derby cover is different from what I am used to not flat and no gasket. Will the earlier one fit or did they change to the new style to give more clearence to accomdate the new style clutch?

 

I believe the early and late are interchangeable, but one uses a gasket, the other uses the rubber ring. What I believe, I could be wrong. I do know the old style three bolt won't work on the new style five bolt primaries!

 

OEM 5-hole derby covers use the large rubber o-ring, 3rd party derby covers use the flat round "pancake" gasket

 

Sometimes you can use the o-ring and flat gasket together for a better seal.

 

The older one will work as long as it's a 5 hole TC cover. You will need a 25416-99C gasket.