Cam chain tension

olympus said:

Are auto cam chain adjusters still available??

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I know that Jim Comstock stopped making them when the IWIS chain was tested. It is quite a big improvement to the Renolds.
I have two of these units from Jim and I have one that went 80,000 miles but it ran with an IWIS.
Like kommando stated above no need for it when using the IWIS and the rubber chain tensioner. You can't buy the normal steel chain tensioner anymore new. Andover only stocks the rubber Mk3 type.

Peter Restaino said:

Hmmm interesting. Same thing happened when I opened up the engine cases and found the main bearings with no interfiernce off by .001 but I got the new bearings and they were .003 thou bigger booommmm

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My shaft was only undersize where it was inside the case, odd I know but softer materials can wear out harder materials given the right conditions.

Stephen Hill said:

The rubber backed tensioner brings its own issues, from what I have read in threads on this forum.

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Its a once only retension, once the rollers are running on the rubber the wear rate drops to virtually nil.

kommando said:

My shaft was only undersize where it was inside the case, odd I know but softer materials can wear out harder materials given the right conditions.

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they should make them oversize

The rubber adds a bit of buffer to a chain tension set slightly tight of 3/16 " of tension.

Peter Restaino said:

they should make them oversize

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They are correctly sized, it's only compromised when the chain tension is set without the correct support and the shaft interference fit is lost by not following the correct procedures causing the shaft to be pulled to one side.

I will buy a new shaft and see what happens and I have that tool. thanks

I get that the intermediate gear shaft should be a light interference in the crankcase. And the interference can be lost, perhaps due to incorrect timing chain tension adjustment.
Let's assume we are not talking about a severely wallowed out bore. And the shaft is now a sliding fit in the crankcase bore.
It is still supported against lateral movement by the crankcase and the timing cover. There is a small chance that the rotating intermediate geat might start the shaft spinning. This would be very low torque action and could easily be dealt with using loctite at the crankcase end of the shaft.

Mick Hemmings... R.I.P. mentions this in his video with first, a loctite fix but he had the bore opened by a machine shop and sleeved with a aluminum bush to bring the shaft back to an interference or press fit. More than one way to skin a cat.

I may be the lock tight fix type. thanks for the suggestions