Topic: 1975 CB550K primary chain

[reddyvv]

I've read so many of the threads on primary chains but couldn't quite get the answer I sought so here goes...

The bike has 8,300 miles on it and the pistons and rings still measure within factory spec, not even close to limit. So I have to presume the bike wasn't thrashed too much. After taking the pan off and inspecting the underside there is no sign of the primary chain contacting any surface of the casings. There is about 1/2 - 3/4" up and down play on the center point.

Since there are no service specs on these chains what is the decision? Keep the chain until you see contact on the casings? Or since I have the top end off and I'll be taking the crankcase out to paint it, open up the case and change the chain?  I really don't want to do the additional work unless it won't last me another 20K miles.

Opinions?

[Tews19]

8k on the engine? She should be good for a long time if properly maintained.

[lone*X]

I have 34K miles on my 550K1 which was well cared for it's whole life with regular oil changes but wasn't spared the throttle either.  A bottom end inspection a few months ago showed no excessive chain slack and no case contact.   If yours received adequate care during it 8K miles on the road I would not even consider a primary chain change.

[xsmooth69x]

http://forums.sohc4.net/index.php?topic=113772.0

lots of pics from dave500

thats what a loose chain does. if you bottom looks like this then ya

[reddyvv]

http://forums.sohc4.net/index.php?topic=113772.0

lots of pics from dave500

thats what a loose chain does. if you bottom looks like this then ya

Yes, I've previously seen those pics thanks. I have no sign of any case contact at all so I guess I'm good to go. Thanks to all for the feedback.

[Duanob]

Worn out primary chains on these bikes are pretty rare. The worst thing you can do to it is to run your bike with the carbs out of sync. But 8000 miles is practically nothing. i wish mine had that few miles on them. 20K + for both.

[bryanj]

550 has more clearance than the 500, if you cannot feel any wear ponts inside the cases you should be OK