cam chain life

[maia 8cars]

I'm pulling the head and cylinders on my recently purchased '78 Special so I can bead blast the bits, the're pretty oxidized and I just want to have a look in there anyway to make sure everything is OK. The engine has barely 6000 miles on it and so far everything looks clean as a whistle internally. I'll be checking the cam chain guide for wear and wondering if I should replace the chain itself. It's a peened link and I believe I can remove the head without breaking the chain by removing the bearings and slipping the cam out. What kindof mileage are these chains good for? I'd rather not spend the bucks if I dont have to. Thanks for any advice.

 

[smokedyerstang]

Better off just replacing it while it's apart IMO, rather than tearing it down again. There are some other threads on the topic.

 

[smokedyerstang]

But if you were to keep the old chain,apparently what you're thinking of doing(not splitting the chain) can be done. Scroll down to iamcarbons video.
http://www.xs650.com/forum/showthread.php?t=16188

 

[azman857]

I agree, while it's apart NOW is the time to do all the things you want(and what your wallet and other factors will allow) to do with your engine. Maybe do some other things to your ride while waiting for the return of your parts.

 

[xjwmx]

Was it too loose to adjust? I've never read of one breaking. Some of them have 80,000 mi on them.

 

[gggGary]

6000 miles, clean inside, I'd reuse it. The front guide and valve seals? no brainer change em. But the chains regularly go 25 30K miles. It doesn't wear sitting there bathed in oil.
Early 70-73? bikes might be a different deal, the early factory drive chains were a real POS.

 

[azman857]

True it's a low milage engine, but it's an 35 yr old engine. How was it stored? Does the camchain have rust on it? Was the bike stored in a heated space or outside. Did all the PO's keep it in good nick or was it treated like crap? For peace of mind, replace the parts ment to wear. I'm replaceing my camchain in my '80 and the engine has less than 25K on it and the tensioner was almost out of adjustment.

 

[maia 8cars]

Wow! Thanks for all the great advice as different as it is, I'll think about it a bit. A no brainier to replace seals and the tensioner if there is wear. I'm used to tearing engines down because of age and mileage and tons of gunk but this one looked super clean when I took the covers off. I'll look at it some more, thanks again.

 

[gggGary]

Front guide, replace wear or not. the glue that holds the rubber on tends to fail. Use the OEM Yamaha guide, it's better.

 

[5twins]

With only 6K I would probably run the chain. True, most stock chains were about done by 20K or so but a lot of that can be attributed to lack of maintenance. The cam chain should be checked and adjusted if need be quite frequently, like every 1000 miles or so. That amount of checking was never called for in the manuals so most of the chains never saw it.

 

[XSLeo]

In my Factory books from 70-77, have a maintenance and lube chart. It lists the cam chain adjustments at Initial 250 miles, 1000, 2000 then every 2000 there after.
My 78E book says Initial at 500 miles then every 4000 after that. The 78SE book says 250, 2000 then every 4000. The 79F, SF book calls for 600 miles then every 5000. the 80G, SG book calls for 600, 3000 then 5000 after.
A lot of variation on those specs. I check it at oil changes. I suggest that it be done then. It can be done as the oil drains. It only takes a minute or so.
Leo