Hurry up with the R&D! I'll be needing one really soon!  

Now, now, let's not go into a violent rage..
But, yes, we were batting around the options, talking about Batman and his gutsy experiment,, and the notion of a slot and spring that would be far more crushable than the chain is stretchable to protect the chain when the pawl grabs a new tooth got tabled.

Violent_Rage wrote on 06/14/16 at 03:18:03:

Still will be awhile before I can put it into production.
Until you buy 1000, springs are $1 each.
new fixturing, another setup, programing, testing...

justin_o_guy2 wrote on 06/15/16 at 10:03:17:

There shouldn't be any motion to wear the spring.
Only 1 in/out cycle per heat cycle, minimal rotational.
Besides a hat would require a smaller spring.

verslagen1 wrote on 06/15/16 at 08:22:10:


I was joking  

Dude's in Orlando and the New and Improved design of the tensioner is exciting. Says a lot about his love of mechanical stuff.

The number of posts reporting issues with the cam chain tensioner obviously suggest a weakness in the original design. And I am very impressed by the improved designs shown here.

I do not know the cause of the rapid wear - or perhaps it is due to build tolerances, that some engines leave the factory with the tensioner already extended near its limit - but generally speaking, poor/dirty oil and chugging do tend to make cam chains wear sooner than under ideal conditions.

What I find puzzling, though, is that MOTORRAD - infamous for destroying allegedly anvil strong engines after surprisingly short distances - failed to mention the cam chain or tensioner at all after their 40,000 km / 25,000 mi long term test. The second camshaft and rockers showed pitting, and 4th gear showed pitting as well, all needing replacement. But neither cam chain or its tensioner, both items considered safe for many more days on the road. Nor did any of the readers who wrote in to share their stories mention cam chain / tensioner issues that I can recall. The magazine also made a Buyer's Guide several years later, and again there was no mention of the issue.

So; is this absolutely universal, or are there engines that will do 60,000 miles on the stock cam chain and tensioner, with others failing at 1/5th that for whatever reason? And anybody placed a sighting glass in the clutch cover so they can monitor the state of the tensioner?