Rear Case Gasket Thickness

Here is a reply from Murray on how thick the rear case gasket should be to prevent shifting and binding problems. Note, I also have cut my own, without problems. I used gasket material from O'Rielly's. The material needs to be at least 13" wide to cut the gasket. The easiest way to do this is to trace around a new gasket and then add the other smaller gaskets in the center of the big one. You do have to buy all the Honda OEM gaskets for the first time, but trace a half dozen or so and you will be set for a good while.

• • Question:

What Thickness is the REAR CASE GASKET? I need to cut my own.

I know Front, Clutch and Timing are more or less non-critical. I've already cut those and they're fine.

But that Rear Cover, I've heard too thin is no good. How much is too much and what is specified?

If too thick, what is the effect?

• • Answer:

8-10 thou (.008-.010) minimum when compressed or it wont shift right.

The new factory one I have in my hand measures .53mm thick. It has not been compressed.

It is 20 thou (.020) thick in inches, for those of you who are metric challenged.

If RTV is used on your back engine cover and your bike is shifting ok, then the forward shim is missing on the shift shaft. Without this shim, the shaft may grind the front of the engine case up.

by Blue Fox