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I have an '02 200 that I recently bought. Tore the topend down to check things out and noticed there was no head gasket, just a very thin silicone like coating. The parts manual has a part number for the head gasket any idea what's going on here? If I reassemble it should i use a gasket? If I don't any idea what the silicone like coating is?

just a very thin silicone like coating

dat's not good.
I'd really check everything out on dat engine, seems like the previous owner didn't have a clue of what he was doing...mkae you wonder what else is messed up with dat bike
so to answer you question: yes use a new gasket.

Re: ' If I don't any idea what the silicone like coating is?'

I know what it isn't!. It ISN'T supposed to be there!

Head gaskets do have a coating on them that aid in sealing, but that sealant IS on a metal gasket material.

The gasket isn't perchance just stuck to one side or the other? And what you are looking at is the remnants of the sealant?

That would be a first, I think.

I would guess someone thought that not using a head gasket was going to be a positive improvement. It would raise the compression ratio alright...but don't know how well that pressure would STAY where it's supposed to. Not well I would guess.

Yah...use a head gasket.

I had a husqvarna that didn't use a head gasket. Instead I would put a little lapping compound on the surface and rotate the head back and forth in a circle. There was a bit of a lip to line up the head w/ the cylinder. Then clean off the compound and bolt things together.

I din't say there is ALWAYS a head gasket used on everything.

The KDX isn't exactly a finely tuned hot-rod motor. So, I suppose the piston crown to head clearance is critical to the point that not having a gasket is going to get parts bumping into one another.

Still it seems kind'a stupid to me to think, 'Let's see what happens!' and not put one in.

Besides...was your husky aircooled?


Not needing to seal coolant would make a head gasket less a requirement, especially if the head/cylinder connection was as finely put together as to benefit from a lapping process.

Aren't you supposed to be working or something? Or...this is one of your six day weekends, right?

Guys my bad......... After reading your responses I took a closer look, with my glasses on this time. There was a very thin gasket stuck firmly on the cylinder. The color matched the cylinder so perfectly it was hard for me to see.

Thanks for all the replies and help

They don't usually stick that well to one part or the other. They can be hard to get off..having been squished to the point they don't want to easily slip past the cylinder studs, but I've not had one really 'stick'.

Maybe your's was coated with something (other than the OEM coating).

The 'very thin silicone like coating' is normal on a KDX head gasket. You will find the same stuff on an aftermarket gasket.

Notice the round hole in the gasket that fits over a water jacket passage in the cylinder? Most of that water jacket is blocked off by the gasket. No need for a 'for future reference'...'cuz this won't happen to you again, but..if you see that round hole..you're looking at the gasket, not the cylinder.

Have fun makin' it run!!!