Cam Chain wear test?

[dbbrian]

Hi folks, hope all are well

I recall when adjusting my drive chain on my RT2 MX and my CB350F, there was a way to check to see if the chain was worn. You would pull a link at the back of the spoket to see how much it pulled away, indicating loose links and need to change the chain for new.

That was a long time ago...

Is this this something that can be done on the cam chain on the XS11? Just about to replace my valve cover gasket, and thought maybe I could check while the cover is off.

Brian

[JeffH]

You running an ACCT or the original 2H9-12212-00-00 cam chain tensioner?
I forgot ...............

Has the cam chain been rattling or noisy? How many KM's on the machine now?
With the cam chain under tension it would be difficult to know if it is stretched or by how much.
Do the Cam 'dots' line up as they should or are the dots off a bit. That's one tell the chain is stretched some.

If its the original tensioner, have you made the adjustment per the manual?

If you have the gasket 2H7-12213-10-00 you could CAREFULLY follow the instructions and go look BUT that first depends on some Key Data and background.

Valve clearances all where you want?? Cam inspection especially the lobes for any marks or wear patterns. We're not sure what to suggest without a tad more info.

Jeff

[dbbrian]

You running an ACCT or the original 2H9-12212-00-00 cam chain tensioner?
I forgot ...............

Has the cam chain been rattling or noisy? YES, ON DECELERATION

How many KM's on the machine now? 86,892 km

With the cam chain under tension it would be difficult to know if it is stretched or by how much. BUT THOUGHT MAYBE A PULL ON ONE LINK WOULD ILLUSTRATE CHAIN WEAR

Do the Cam 'dots' line up as they should or are the dots off a bit. that's one tell the chain is stretched some. WILL CHECK WHEN COVER IS OFF

If its the original tensioner, have you made the adjustment per the manual? YES, ORIGINAL, YES ADJUSTED AND SEEMED NOT TO IMPROVE. ACCT IS ON THE TO-DO LIST

If you have the gasket 2H7-12213-10-00 you could CAREFULLY follow the instructions and go look BUT that first depends on some Key Data and background. I HAVE THE GASKET

Valve clearances all where you want?? CHECKED LAST SUMMER ABOUT 5K AGO

Cam inspection especially the lobes for any marks or wear patterns. OK

We're not sure what to suggest without a tad more info. A BIT MORE. THIS WAS A QUESTION ABOUT TESTING FOR CHAIN WEAR. PULLING ON A LINK AT THE MIDDLE OF THE SPROKET TO SEE HOW MUCH IS COMES AWAY FROM THE SPROKET, AS A WAY TO MEASURE WEAR. MAYBE ITS AN OLD SCHOOL THING.



Jeff

Answers above in all caps...sorry for YELLING, lol

Brian

[bikerphil]

Quarter inch stretch at the top between the cam gears is properly adjusted.

[JeffH]

Think about it !!
Then prove it to yourself. Get a crowbar and try and lift that chain between the sprockets. (not really) Think about how much give there possibly could be in that only 3 inches of chain between the cam sprockets. As Phil said, see if you got some play, no play or that 1/4" wiggle.

Four foot long drive chain between two drive sprockets, yep can maybe work on a long chain run. Chains between the cams is what? 3" and the chain is under tension with tensioner and guides. Nice try but wrong test to prove what you want to know. Dots alignment is good place to start. If real concerned pull the Tensioner and look at how are out that push rod is.

Seems you are concerned about it so i'd just replace the cam chain when you do the ACCT. With the Tensioner out can then check how many MM it takes the tensioner to tighten the chain. If it is rattling too loud on decel then I'd do more than that subjective 1/4" play test.

87Km is low mileage to have a problem but who knows till ya go look. Been Road Racing that thing?

Jeff

[bikerphil]

With the ACCT, over 100k miles should be no problem, I have two engines running that way, maybe slight power loss though. With the OEM tensioner, limit is about 60K, YMMV.

[motoman]

For checking cam chain adjustment or replacing the poor adjusting stock setup with an auto adjuster(ACCT), I fully agree with JeffH and his threads pertaining to this scenario. Replacing stock adjuster with an ACCT IS your best bet. Problem with stock adjuster is the pinch bolt does not hold chain tight under a decell(and was found to be true under bike testing back in late 1977 early 78).

[3Phase]

What Jeff said, Brian.

The camshaft timing dots will move out of time as the cam chain wears.

That's about the only 100% reliable check you can do for cam chain stretch.

[skids]

I can’t imagine pulling the chain behind a sprocket for a check. Yes, if the tensioner set bolt is accidentally stripped, you will be looking for valves. There are other things that can wear such as sprockets and the chain slipper. Measuring the amount of adjustability on the OEM tensioner ram is the best way I know to see how much tensioning you have left. I thought I was just about out of adjustment once and I bought a new chain (emuma?). I was disappointed when finished because it was about the same position on the CCT ram, however there was still some available adjustment. That was not the “heavy duty” chain. Also beware that there are continuous chains (not easy) and ones with a master link.

[skids]

PS, the automatic tensioners I have used have more extension on the ram for adjustment.

[3Phase]

PS, the automatic tensioners I have used have more extension on the ram for adjustment.

I worried about the longer ACCT keeping a pooched cam chain tight until it snaps and you replace valves but then I thought about it a little more.

There's not much different between replacing valves that were bent because an overstretched cam chain broke with the ACCT and replacing valves that were bent because the cam chain -- stretched, normal or brand new -- jumped time with the OEM tensioner.

[jetmechmarty]

dbbrian,

In your first post, you are correct. You grab the chain right in the middle of where it is riding on the sprocket. Not between the sprockets. Try to lift the chain away from the sprocket. If it won't move, it's good. If you can pull it away, and see daylight, you should consider a replacement. On a small sprocket like that, you shouldn't be able to move it much.


The image is bicycle, but you know what you're doing. Buy a new chain and a new tensioner. It will give you something to do while you're stuck in the house and on your side of the border. When in doubt, replace it!

[dbbrian]

That last picture is what I was recalling. So my chain does not pull away like that.

I lined up the crank with the "T" timing mark and the dots are past the makers on the cam. Not sure how far is too much.

[3Phase]

It looks like it's off a tooth. Advanced.

Normal camshaft timing marks:-

[skids]

That last picture is what I was recalling. So my chain does not pull away like that.

I lined up the crank with the "T" timing mark and the dots are past the makers on the cam. Not sure how far is too much.

You might want to check to see if “T” is indeed at top dead center.