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XR650L valve cover gasket thickness

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I hand-cut a replacement valvecover gasket on my XRL, only to remember that the valvecover doubles as the camshaft retainer. Now I am concerned that the OEM gasket from Honda is a precision thickness for the cam...

The material I used was a very thick - 1/16" - roll of Felpro rubberized fiber gasket material. I saw the rolls sold in 1/64", 1/32, 1/16, and 1/8" thicknesses.

The gasket I removed was old, brittle, compressed, and aftermarket. It also had spontaneously cracked (probably from shrinkage).

Is anyone aware if the gasket thickness is a critical issue, and if so is there any data for OEM thickness - both new and when compressed?

I went ahead and ordered the unbelievably expensive $50 paper gasket from the local stealership and it will arrive in a week, but I would really like to get back on the road before then.

Thank you!

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I'd have to check the specs for cam to center bearing clearance, but I suspect gasket thickness is an issue and not an area I would go cheap on...

 

Although the OEM gasket is a bit pricey, it is high quality and can be reused.  MCMA11 on Advrider detailed the process, I just tried finding the link to no avail but if you peruse the XR650L thread, you will find it.

 

Basically, when you remove the valve cover, make sure you clean off the old residue and apply some RTV or similar (I use the Permatex Ultra Black, never had a leak) on the gasket surface and re-install.  The last time I did mine, I used steel wool (fine) to remove the old material off the gasket as well.

 

I've never had a leak reusing this way and can usually reuse 3 or 4 times before I'll bite off and get a new one.

 

On another note, there are other places to order parts than the dealership (although I order from them as well from time to time).  Try looking around online, I just found it for $30.11 at one online outlet...

 

Dealerships don't seem to be there for after sale support, their only job seems to be to get the bikes out the door...

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OEM shim/gasket is .013" thick.  It is single layer metal and does not compress.  It is embossed to help create a seal.  

 

You should end up with .002" center cam journal clearance when all bolts (including that large center one) are torqued.  Runout of the cam should be checked so that it doesn't exceed this clearance and touch the valve cover.  

 

I'm pretty sure I found the actual clearance spec when I was rebuilding mine but I can't seem to find it in the manual right now.

 

I went through all this recently and a much smarter and experienced engine builder (mcma111) warned me before I messed up by trying to use an aftermarket "paper" gasket.  I thought I had done my homework but it will compress and can cause clearance issues.  Some aftermarket gaskets are fine but it isn't worth saving the money to get the one that isn't fine.  

 

Use the stock metal gasket and apply a thin, very thin, layer of a good gasket sealer on both sides of it to take care of any scratches or variations in the sealing surfaces caused by old gasket removal. 

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