Has my camchain tensioner failed?

[mattijw]

Hello everyone!

I think my front tensioner has failed, I did the stopper mod approx 1000 miles ago and the bike has been laid up for winter. I just put in a new set of clutch plates and ran it to the garage for petrol. Then as it was idling it started to tick .......... So I've done a little video and I'd appreciate any advice


https://youtu.be/dxINYOB8Nsg

[Steve97]

having had one go on a stopper mod then i would say yes it sounds familiar
set up the timing marks and whip it out to check it
follow the guide on here if you didn't do stopper mod yourself

[VTR Phoenix]

I wasn't sure whether to comment but I thought cc would not continue to make noise if bike was revved up but clearences/valves would make noise continuously getting faster as you increased the revs. With the stopper mod not allowing the chain to be loose enough to jump teeth would it be loose enough to continue to rattle the higher the revs?

[tony.mon]

Yes, it can.

To check, undo the end cap from both cct's (one at a time) and insert a small flat blade screwdriver. Turning the screwdriver against the spring, then allowing it to release, proves that one or both springs are working normally.

If both springs are ok, then stop worrying....
If one has gone, you have to buy a new standard cct and redo the stopper mod on the new one, then reinstall it.

[sirch345]

I wasn't sure whether to comment but I thought cc would not continue to make noise if bike was revved up but clearences/valves would make noise continuously getting faster as you increased the revs. With the stopper mod not allowing the chain to be loose enough to jump teeth would it be loose enough to continue to rattle the higher the revs?

I had the front CCT go (which is the more common one to fail) when on a ride-out. There was no doubting the CCT had failed by the noise it was making, but with the Stopper Mod fitted I was able to ride my bike the 15 miles back home without any worry of damaging the valves or worse. The noise was there no mater what the rev's were, although I didn't over rev the bike on the way home.

Listening to the OP video, it's not 100% possible to say it is a failed CCT, although it's possible it is. I would do what Tony suggests above before you go any further,

Chris.

[mattijw]

That's a great idea. I never thought to check the spring tension in situ.

I did the stopper mod myself so I'm happy enough removing them and I've already decided if I'm going that far I may as well go fully manual. So either way I'll find out. I don't think I'd even be happy starting it again until I'm sure it's OK. The noise as it stands is from the top left of the motor and sounds worse on the overrun after a blip.

When I did the stopper mod I took a fair bit of care and there was only maybe 3/8 of a turn of slack so I think it wouldn't back off far if it as failed


Thanks for the advice, some great answers.

[sirch345]

That's a great idea. I never thought to check the spring tension in situ.

I did the stopper mod myself so I'm happy enough removing them and I've already decided if I'm going that far I may as well go fully manual. So either way I'll find out. I don't think I'd even be happy starting it again until I'm sure it's OK. The noise as it stands is from the top left of the motor and sounds worse on the overrun after a blip.

When I did the stopper mod I took a fair bit of care and there was only maybe 3/8 of a turn of slack so I think it wouldn't back off far if it as failed


Thanks for the advice, some great answers.

Which suggests it is the front CCT which has failed, and as I said earlier is the more common one to fail,

Chris.

[mattijw]

Yeah it seems that way. I'll post up what I find, if it has failed it's another save for the stopper modification.

[mattijw]

So I took off the tank and checked the spring tension on the adjusters with a small screwdriver. Both felt fine, turned back half a turn and felt the stopper then sprang back to usual tensioned position. But I still have the noise. It's very definitely from the front cylinder region. It didn't seem to be there until the engine warmed up. All I can think of to do is remove the front cam cover and check the chain tension. I recall reading that there should be 7 or 8mm of play. Maybe check the valve clearance too?

Is it possible for a tensioner to become too weak? Or partially fail?

Another video!

[AMCQ46]

I had a noise at idle on mine and it turned out to be the stopper rattling up and down in the CCT! and because I had used Aly tube it was wearing with the vibration and getting more clearance till it could make a noise.

replaced it with a steel bolt shank and the noise stopped

[mattijw]

That's a possibility I guess. I did use a stainless unthreaded shank though. How did yours sound? Mines a definite tapping / slapping on the overrun.

[tony.mon]

. All I can think of to do is remove the front cam cover and check the chain tension. I recall reading that there should be 7 or 8mm of play. Maybe check the valve clearance too?

Is it possible for a tensioner to become too weak? Or partially fail?

Another video!

The 7 or 8 mm is for manual tensioners, not stopper mods.
And yes, the tensioner spring can become weak before failing completely.
But it doesn't stay that way for long, and you should be able to feel the difference between both tensioners.

It's easy to check- with the engine running, small screwdriver down the end of each cct in turn and slightly tension the adjuster screw. If the noise disappears, you need a new cct with a new stopper.

[adewhitmarsh]

Best thing to do is change to manual ccts,you won't have to worry about failed auto's or stopper mods anymore.once fitted you may need to adjust every 5000 - 10000 miles .I know owners will say,but you sell them so you would say that,but I get a lot of positive feedback from my customers.

[mattijw]

Just a quick update to this problem in case it helps anyone in the future.

I did indeed end up changing the tensioners for ade's manual items. With fresh honda gaskets they went on with no issues.

And the noise is gone! I can't find any faults with the old tensioners so I suspect as a previous poster found the stainless bolt had just enough freedom to rattle. I guess the rear would be damped by oil but the front is too dry. Perhaps just a dab of grease when installing would have helped. No matter, as the permanent manual solution is done now.


Thanks to everyone who helped!

[sirch345]

Thanks for letting us know, glad you've fixed it

Chris.