sorry, but in my opinion this is nonsense (cold treatment of chain, smoothen some teeth of the tensioner and so on).
In fact, deactivating some teeth of the plunger would have such negative effects and no benefit. The chain may lash and churn nearly free. You don't want that!
Don't tinker on symptoms, face the cause!
It is not the chain itself causing any issue, generally. The same chain (at least the same type of chain) works a lifetime and more in other kinds of engine makes. (But not to speak about cheap aftermarket chains. They may have very poor quality, don't trust them.)
We can achieve lifetime on the enginge with the chain.
The whole thing gets the most trouble, if the plunger gets out more and more with time and miles done. Even with a brand new chain the original plunger comes about half the way out, maybe about 10mm, some more or less. Why it is not reasonable to blame the chain for any instance, let's see.
Then, under given circumstances the material of the cylinder part of the tensioner does not withstand very well the several loads coming up with the miles you've done with that stock construction. Which loads that are, see later.
Take that tensioner, take out the spring and watch how slacky it can be in its working position, even in a good used state. Then push it down as much as you can. You even may feel a bit compression effect with some added oil. See?
Then consider again, it's coming out about half the way on a new chain. It's a bit of math to see, the "growing" of the slackiness right in the tensioner itself does not rise in a linear way, it is more, it is more exponentially.
On tensioners that are just before disaggregation you will see some evident funneling wear of the sleeve part. This actually starts with stock equipment right from the first firing up.
Then consider the rear chain guide mounting. It has a rubber coating even in the bushing for the upper bolt. It allows some mild slack itself in the way of torsion or tilting. Have a close look on a used chain guide, the bushing got a bit oval. Feel it with the according bolt...
Feel the difference in play in horizontal direction and vertical direction.
You now should understand why the chain can produce signs of wear on the small inner side guide and decentered marks of wear on the lower part of the chain guide track. Or the chain even tears off parts of the small side guiding rim on the chain guide.
So chain guide bushing, tensioner assy and the chain itself provide side slack by tilting chain guide and lateral movement.
That's the way to consider the issue in a global way.
Aother additional point is the way the tensioner grips on the chain guide. It is not applicated on the center of the guide where it reasonably should be, it's on a side attack. That way it can force a skewing movement. Still hardened steel but it has to have some clearance between bolt and the hole in the plunger to work. Not a very good guidance at that point, too. That part of sheet metal on the chain guide connecting to the nut where the bolt gets in (right behind the tensioner) does not have contact to the tensioner housing and therefore there is no retaining effect. Both parts only then get in contact if the whole system is going to be worn and you will see scratch and slap markings of it on an heavily stressed and worn system.
Logically, the tensioner system is on the load free side. Most of the unwanted wear occurs (by empiric investigations, comparisons and inquiries) if you run the bike on low and lowest revs. OK, how the bike is running there, you might love the way the engine provides torque right from the cellar of the tach numbers. But, considering the chain tensioner, it is unhealthy for that system.
In the fact of low revs and load regarding the crankshaft, the deceleration on the compression stroke followed by the acceleration through combustion is a remarkable number.
That gives the tensioner system oscillation pulses and it does.
It oscillates in any direction it can do.
(The more revs you give the engine, the more all the rotating heavy parts like flywheel, generator and crankshaft do store energy from the combustion stroke, so the difference in combustion energy and stored energy decreases in increasing revs, roughly seen. Avoid much throttle and that way heavy loads on low revs, how fun they may be to you.)
That way the chain may slap against the guide and/or lateral and may have a short rest on the rim of the guide. Leverage effect causes load on the upper bushing, lower side on bolt and eye. The chain guide will tilt a bit. Misleading the chain on a tilted guide may then force the tensioner to come out one more click, then the chain jumps back to the right position and voila... more tension on the chain as it should have. This produces heavy stress and wear on the chain. Additional heavy wear! That way it stretches out the most.
(remember, even when the jug heats up and stretches therefor, the chain will also! OK, aluminium has a higher delta-t than steel but the tensioner is on the slacky side but this difference in delta-t will make only some hundreds of millimeters or may be at least a tenth of a millimeter in difference. No way for abusual tension here. See the rear chain guide is curved a good bit and can take a bit load from this effect. The front chain guide cannot, it's fixed at both ends, therefore limited, no bow-effect or spring function there.)
That way the verslavy (and other approaches of the same direction) gives the whole system a more straight working condition with the fact to avoid as much side slack of the chain and guidance.
To achieve nearly the same as the verslavy does, one can shorten the sheet metal part (connecting piece from guide to the riveted nut) on the chain guide. Measure, cut, weld good (inert gas welding, never try gas welding, remember rubber would burn off and hardened steel would weaken!) and flatten out the welding according to the backflange of the alu tensioner sleeve part.
Another way could be the bolt
behind the tensioner, but this would be a way of some machining toys and not only cut, align, weld and grind off excess welding.
Whatever approach you prefer to get the tensioner in as much as possible to work, the benefit will be a better guidance of the chain.
And the benefit is also to have sorted out that issue for nearly a lifetime of the engine or even more.
In conclusion it may take a new rear chain guide if it is worn too much, it may take a new tensioner assembly if it is too much damaged (missing latch spring, broken or chewed up main spring, the bore more a funnel than a sleeve and so on). And if you feel better, then take a new timing chain and do the tweak having nearly the full way of the plunger. And go on riding. If you have it done right, you couldn't care less about any timing chain issues.
Again: With every effective improvement of the timing chain tensioner system the elongation of the chain will occur only in a very slight manner. If there would be anything true with temperature effects, the chain would still stretch. But it does not. Not therefore.
Ah, OK, maybe 10 Angstrom or so.
Sorry if you could not understand something, I'm not a native speaker of the english language. Please ask if you feel lacks of expression or terminology.
Regards, Lou
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