valve cover gaskst

Is the valve cover gasket the same for a 82 xj750 maxim as it is for a same year or 81 xj650 valve cover gasket ? Thanks

 

Definitely not the same as 80-81 XJ650. However, All XJ750 and all the YICS XJ650 (1982+) use the same rubber gasket.

 

Is that the gasket I need when doing a valve adjustment or is it the head gasket ? thanks

 

The first one

 

You need the gasket and a set of the metal/rubber composite "donuts" that go on the bolts. The bolts have stop collars on them to prevent overtightening, so those "donuts" are what actually push the cover down onto its gasket. If the donuts are all petrified and squashed out then even a new gasket will leak.

 

FWIW, the molded gaskets on the YICS motors have the half-moons molded into them... They're still prone to leaking though. Nothing a little Threebond couldn't cure.

 

Thanks for the info, Right now the bike runs great and no leaks. I don't think the bike needs a valve ajustment right now But, how will I know when it does ? Thanks (The bike runs and sounds great as it is.)

 

There are two ways you know the valve clearance needs adjustment:

1) You measure them with a feeler gauge and find them out of spec
2) You burn a valve and/or seat because they're too tight

 

You forgot #3:

You have no hard evidence or proof of when they were done last (or ever) and the bike has more than 5000 miles on it.

Ya wanna bet $5 per out of spec valve on it? How about $80-$90 (the cost of a new valve+seal) per? Oh yeah, and cost of a head gasket, too.

 

Not if you replace the donuts when you replace the gasket. Mine's been back on and off my '81 at least three times in the 9K+ miles I've put on it; no leaks.

 

On anything YICS, the donuts are part of the gasket, so they can't be replaced individually

EDIT: I guess it's not so much the YICS thing.. Just something Yamaha started doing on later models.

 

Except for XJ650 Turbo and XJ1100 engines.......

 

He's talking about the rubber donuts with the steel caps that go on the cam cover bolts. They're not part of the gasket.

I think you're referring to the half moon pieces that fill the void where the cam journals were bored into the head. Those are part of the cam cover gasket on "newer" models.

 

Oh, *derp* sorry