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Speedchaser, I have been told this product is great to use on a surface that is not flat between the gasket.It supposedly will harder only when air is not present-I have 2 case halves that do not match well and lapping has helped but still have a slight variation on 1 surface (0.008mm). Manufacturer makes this for surface gaps of 0.016mm.Have you ever used this and if so what opinions do you have on it. A local machine shop here actually 2 of them recommended for my application to use this.I appreciate yours or anybody's help.

that is a Retaining Compound that will not work for the case halves but it might never used it like that

I would think if you have that much differences between the to case halves you would need to build them up (with weld or some sort of metal epoxy)then re lap them in or use Yamaha bond

but you should have enough material and tolerance to lap them flat
you should check on how much side to side play you have between the main bearing on the crank to the case halves.
that should tell you how much you can lap off
or you can lap more off then run a thicker gasket . to get back your side to side play

hope this helps

speed

This is for the jug base surfaces on the case themselves.I should have been more clear, my apologies. Still the same though correct? Thanks for the help!!