I have no idea why the manufacturers will not acknowledge the fault unless they just figure to see if they "get away with it" until out of warranty when it finally is bad enough to cause issues in running, period.

As for dealers and mechanics, they have to understand the issue, which this one apparently has a slight concept. The thing they don't realize is that "caught between two teeth" is where it allows the rack to snap back and forth, like constantly missing second gear, damaging the teeth of the rack and the pawl until, much like the second gear dogs getting worn to the point where the transmission pops out of gear, the edges round off and it won't hold even if it got far enough.

That is the evidence I see in the tensioners I've had in my possession. If it was just "stuck between two teeth" you wouldn't see the wear pattern over three to five teeth and would not see that one tooth polished as well as the back side of the rack being polished smooth and shiny where it constantly is sliding in and out. That is the actual evidence of the problem. It's as clear as seeing seize marks on a piston, rings, and cylinder or score marks in cam journals... IF you know what you're looking at. In my previous work as a quality technician and engineer I did a lot of diagnostic inspection on worn and failed parts. I approached this with the same inspection and engineering process when I started getting deeper into making the parts for more and more bikes.

I will say, too, that the chain is pretty robust and may not be totally trashed. My 250 had 15,000 miles and I have no idea how long the tensioner was bad, but putting in the manual unit took care of the cam drive noise. Anyone else know about how long (miles or time) they had cam drive rattle, let us know so we might be able to have an idea about this. I actually would be most concerned about the sliders being damaged or if there's enough chain slop, the chain snapping or jumping time. I have read of one KLX300 rider and actual contact with another, who had the cam chain break. The one I communicated with bought the bike with it broken, replaced the chain, but not the tensioner, ran it for a while and broke another. I'm betting controlling the chain slack with the manual unit will end the chain breakage.

Now a side comment, when lugging down a bit I noticed I have some rattle or piston slap as it is called, where the piston is rocking and clicking. Clearly the noise is in the cylinder and only under heavy load at lower rpm, around 3000-5000 rpm (same area as the cam chain does it without load). If I rev the engine a bit higher I have less noise. I was that low way too often in the deep sand due to the problem with steering constantly getting me from a decent pace to a near stop in second, or working first at lower rpm trying to move and still maintain control... obviously I lost that battle and ended up going over as the bike washed out on a turn, breaking my ankle. Bummer!

My 650 piston rattle a bit as well, actually since it was rebuilt with proper piston clearance, so I'm not too concerned. I mention this because it is something others may encounter. It also emphasizes why I say to listen carefully for where noises may be coming from. Besides, if it gets bad enough in a few years maybe I'll do a 351 kit... but my interest in bigger power with same weight will likely win out before the piston slap gets that bad.

 

I too am looking to buy my second KCCT as my new (to me) 09 is clickin' like a chicken at 30000 km. I know, the chain MIGHT be shot but the manual one is a lovely thing to have, and I'll fix the chain if this doesn't. The manual tensioner made my 2010 klx250sf purr like a kitten, can't wait for the dirty S to sound the same

 

This thread is kind of old, so I figure I'd put in the new email address kriegercct@clems-garage.com