Top End Gasket Questions

When I bought my bike it came with an already opened Athena gasket kit. Yesterday I pulled everything out to make sure everything was accounted for and noticed the base gasket had been folded in half and there was a small tear starting where it had been folded... careless.

Needless to say I will not be using this base gasket, but this got me thinking about gaskets in general. I am wondering if I should buy a Vesrah kit and make a hybrid kit between the 2 of them. That way I would have the O rings for my tappet covers, the valve seals, the thinner head gasket and a new base gasket between the 2 kits. Are there certain gaskets that people prefer between the 2 sets besides the head gasket?

My other option would be to purchase a base gasket only. Is this one from Mikes any good?

https://www.mikesxs.net/yamaha-xs65...w4aLlencQMxEYPzc86FLmqX9E_vVRe-IaAh6NEALw_wcB

If not, are there other options for buying just a base gasket? Is there any issue using the tappet gaskets that come with the Athena kit on my covers that came with O rings from the factory?

The tappet cover gaskets will work but they incline you to overtighten the nuts. gggGary sells some good o-rings for there. There are also o-rings at the base gasket. If you mean valve stem seals, I would get genuine Yamaha since they're still available.

P.S. when you need just one gasket, ebay seems to be a good source for cheap nos ones.

I did mean valve stem seals. Are the Athena ones really that bad? It would cost me $43+ for genuine Yamaha through partzilla and I already have the Athena ones. I'd prefer to spend that money elsewhere if possible.

The Athena kit came with the O rings at the base but not for the tappets. If the base gasket only from Mikes is any good I might want to grab some O rings from gggGary if he has some! Thanks for the heads up.

MadeThatMyself said:

I did mean valve stem seals. Are the Athena ones really that bad? It would cost me $43+ for genuine Yamaha through partzilla and I already have the Athena ones.

Click to expand...

What you have might be great, dunno, I just meant starting from scratch or if they were cheap I'd get oem seals. Surprised they're $43, but I had mine a long time sitting there waiting.

Yeah I was surprised they were that expensive as well. $8.84 ea plus shipping...

I've never had any issues with the Athena valve guide seals but if I was to use something else, it would be viton ones from eBay, reasonably priced, supposedly better, but unfortunately out of stock at the moment .....

https://www.ebay.com/itm/YAMAHA-XS6...m43663.l10137&nordt=true&rt=nc&orig_cvip=true

My Athena head gasket did give out on me and start leaking after about 8 or 10 years. I don't know if it was the gasket's fault or mine, or if eventual leaking head gaskets are just the nature of the XS650 beast. When I replace it, I will try a different brand one.

I don't care for the valve cover gaskets and wouldn't use them if the covers had o-ring grooves. The P.O. of my '83 put them on during his rebuild and they were just awful - leaking and butt ugly, lol. And his liberal plastering of gasket sealer didn't make cleaning them off of there easy either. The stock o-rings are a rather odd 2.8mm diameter and not easy to find, but luckily the commonly available 3mm diameter fits and works perfectly .....



MikesXS asks a ridiculous $4+ each for these o-rings. Ten packs of silicone ones can be found on Amazon or eBay for less than a dollar per o-ring.

I could live with 8-10 years based on already having the Athena head gasket. Thanks for the McMaster-Carr O ring recommendation as well.

Looks like the only thing I still need to figure out is a base gasket. It looks like there are some NOS gaskets on eBay for around $10. Mikes has the one linked in my original post for $15. I'm going to be placing an order for the front cam chain guide and a few other things from Mikes soon so if that base gasket is worth it I'd like to order it at the same time.

Any base gasket opinions one way or the other?