ZXR750 J cam chain tensioner

[Ascalon]

So the guys setting up the carbs on my J1 reckon that the cam chain is noisy. After just 25k miles I suspect that the chain is OK but the tensioner might be the problem.

Is it necessary to replace the tensioner or would a good clean and grease get it sorted again?

This is a ratchet type auto tensioner is it not? Any other models that share the same bit?

Cheers,

A

[ZXRRDave]

So the guys setting up the carbs on my J1 reckon that the cam chain is noisy. After just 25k miles I suspect that the chain is OK but the tensioner might be the problem.

Is it necessary to replace the tensioner or would a good clean and grease get it sorted again?

This is a ratchet type auto tensioner is it not? Any other models that share the same bit?

Cheers,

A

A strip and clean with a fresh gasket should see you right.

Mine was a bit sticky on the L when I got it. J/K/L/M models all use the same motor so you shouldnt have problems finding bits if replacement is necessary. The tensioner blades should be fine as my M has done over 30k and they still look like new.

If you feel like it a manual one shouldnt be too hard to source but not really necessary.

One other thing to consider is your mechanic may be more used to recent machines and isnt familiar with the fact that even when running perfectly early 90's kawasakis normally sound like a spindryer full of ballbearings being pushed down a set of stairs.

[Barry]

The J/K & L/M actually use slightly different tensioners, but they are all interchangable. Also, they dont have a gasket, they have a rubber 'O' ring.

Yes it's a ratchet tensioner, you can just remove it, reset it and refit it. But you must turn the engine over by hand (19mm spanner on the ignition rotor) before you start it for real or you'll risk it jumping teeth!

I use a manual tensioner in my M, mainly because it's in such a high state of tune and has lots of expensive internals, I dont want to rely on the stock tensioner!

[TriGGer]

Might just be worth checking the alternator drive chain, easily confused with cam chain noise and twice as likely to go baggy.

[Ascalon]

Well, good news and bad on this front.

Picked the bike up yesterday and it turns out that the reason it sounded like a bag of spanners was that the valve clearances were all over the shop!

One exhaust valve was zero!

However, the guy who did the work is an old hand and had a big box of shims and 10 needed changing. So, then he did the carbs and they were way out too. Worryingly there was also a fair bit of rust still coming frmo the tnak. So I think a Petseal job is on the way.

So now she idles nicely and picks up off idle very nicely indeed. In fact, the mechanic who gave it a shakedown, not the guy who did the work, remarked on how powerful it felt through the mid range and into high revs — Score!

Now, the only thing bothering me is the fact that from about 6-7k there is some farily intrusive vibes through the pegs. Can't tell if it gets worse after about 7k because she pikcs up so quickly form there to 10k plus that its hard to tell what's happeneing!

The mad thing is, with the suspension rebuilt and tweaked a bit, you can be harsh with the throttle and it is very...entertaining!

Is that characteristic for the J motors? I seem to remember reading that the Hs were very, eh..."characterful" in that way. Is a J similar?

Anyway, will be riding it for a while as my 4s needs open heart surgery with suspected buggered big end bearings.

So, all's well I suppose...

A

[Ascalon]

Well, another happy bit of trouble shooting concluded with me finding a set of wheel balancing weights in the shed this morning as I tidied up.

I was happily sweeping the floor and trying to figure out why the bike mioght be vibrating the way it was, when I disturbed bit of timber and found a set wheel weights underneath! That would certinaly explain the kind of vibes I was feeling! So, that's an easy fix then!

A