Topic: Another brain fart on my part, Cam chain guide broke

[clarkjh]

Just took the head off my 74 550k to replace the head gasket that I blew, the cam chain guide is broke and very worn now .  I was sure I had everything installed right.  Any ideas what I missed?   I don't want to break the next one I get, (have to find one first) or the chain.

Thanks

James

[Tim.]

The guide was new?  Did you replace the slipper (the contact face on the tensioner side) at the same time?

Not an expert myself, but the only way I could see a guide being prematurely worn and actually broken is a cam chain that is way too loose.  This would point to the tensioner.

Also, you might consider a new chain.  I recently replaced my chain and sprocket.  The chain can be replaced without removing the cam or tearing out the bottom end.  The stock chain is endless, but if memory serves me right, I think one of the 400's or 450's or some other model had a master link.  I bought a new 550 chain, and then it was broken and a new master link from the 400/450 was installed.  There's a special Honda tool for putting the master link rivet in place - makes it an endless chain again basically.

[kghost]

Just remember that a rivited chain is about 90% as strong as an endless.

[bryanj]

The link is a cb450 twin or cb500 twin part and all endless chains were built from links in the factory so why should a supplied link, correctly fitted be any weaker?

[kghost]

Because of the way its rivited. From the factory the chain is hammer formed in a die. When you install a link with the old squeeze rivit tool, its just not going to be as strong.

It probably won't be a problem unless your running high hp or rpm. Like with a high output motor.

[clarkjh]

I'm not planing on hipeing this motor.  Just want a round the town and short trip scoot.