Confusion on everything cam*

[xs650newb]

Hey everyone.

So, I have a 1980 XS650.

I am doing my first top end rebuild because I noticed black flakes in my oil and I have 20K miles on the bike.

I am obviously replacing the FRONT cam chain guide.

My question is, if I have 20K miles, should I replace the cam chain itself and the rear cam chain guide?



Best,
Adam

 

[blackbetty]

Hey everyone.

So, I have a 1980 XS650.

I am doing my first top end rebuild because I noticed black flakes in my oil and I have 20K miles on the bike.

I am obviously replacing the FRONT cam chain guide.

My question is, if I have 20K miles, should I replace the cam chain itself and the rear cam chain guide?



Best,
Adam

If you're pulling off the top end anyway, why not?

 

[XSLeo]

The rear guide/tensioner is a very robust part and seldom needs replacement.
The front guide is the one that needs replacement.
A new chain and the front guide are a good idea. The guide because it's failing, the chain because an old chain lets the cam timing be late.
How is the compression? If it's good then just replacing the guide and chain my be all you need. While the head is off removing the valves to replace the seals is recommended. While the valves are apart lapping them is good.
In the repair manual it tells how to check the rod big end bearings. Another good idea.
While apart checking a few things like the starter gear spring tension, the springs on the shift shaft and shift drum. Inspect the clutch for wear.
Replacing the oil seals on clutch pushrod, the bushing behind the seal too. Seals on the shift shaft, transmission main shaft. All these can be done without splitting the case.
There are more things, just can't think of them right now.
Leo

 

[xs650newb]

The 'why' is because of money. If the two parts (Cam chain and rear cam chain guide) are out of spec then I will replace them, but I was wondering from the experience of others how many miles it generally takes for these pieces to go the way of the dodo bird.

 

[xs650newb]

XSLeo, that is exactly the reply I was hoping for. Thanks a bunch.

The compression was great before tear down.

Another question for you: In order to accomplish these repairs which gasket set do you suggest I purchase?

Best,
Adam

 

[5twins]

Buy the complete engine gasket set. You'll eventually need and use most everything in it and it's cheaper as a kit. Replace the chain, it's toast. They can and do last longer but the thing is, P.O.s never gave the chains the proper maintenance so @ 20K, they're toast. If you keep your new one adjusted and check it frequently (every 1000 miles, do it when you change oil), it will last much longer.

 

[XSLeo]

Yes, just as 5twins says, get a complete set, I might add get the complete oil seal kit too. You will need at least a few of them and the kit is cheaper than buying by the piece.
Leo