RE: The KACR on the KLX250S
 

Actually, I was just getting ready to ask Marty about whether the aftermarket cam he pointed to in another thread had a compression release or not, and if it did, perhaps it is more reliable than the stock version. Marty pointed to this cam earlier for the KLX250R / KLX300R:

http://www.webcamshafts.com/kawasaki-moto.html#6a

.350
272
229
101
Larry Roeseler's favorite. Quick acceleration with plenty of mid and top end power.
N/A
60-431
$275.00
N/A

That alone may be worth investigating a pair of aftermarket cams. Also, is that $275 for both the exhaust and inlet cams? If so, that's a far cry from what the OEM source wants for just a single cam shaft, let along the pair.

The ONLY thing I worry about with replacing the cam with something like that is typically that means advanced timing for better performance. But usually that comes at the cost of faster valve and valve seat wear. For example, this is one of the areas that typical "off-road" bikes vary from "MX" racing bikes and the MX variety generally requires far more frequent valve maintenance and rebuiding by comparison. Any thoughts on that?

RE: The KACR on the KLX250S
 

Yep, I fully understand. I wouldn't want the extra wear. I'm into riding, not keeping the beast running.

One of the reasons I chose that particular grind was the "ramp" I saw. If you notice, the duration at .000 is 272 degrees. At .050 it is 229 degrees. That's a difference of 53 degrees with .050 clearance, a fairly mild grind. Not one that is going to slam valves, make it hard on your engine and all.

Now if you look at the last cam in the chart, the one for "Excellent mid and top end power. For racing engines only" you will notice that at .000 it's a .352 lift and 263 degrees of duration, at .050 it's 243 degrees of duration. This is a cam that opens the valve trail very quickly and closes it the same. They want to build cylinder pressure pretty high and make the cylinder work.

One of these sets of cams might be the next step in the evolution for MORE POWER!

RE: The KACR on the KLX250S
 

Pretty reasonable price too, especially if it avoids a potentially bad situation with the stock compression release.

RE: The KACR on the KLX250S
 

For those with long-term experience with Kawasaki or the bike industry in general, what could we expect from them if this does turn out to be a pervasive issue?

First of all, let me make it clear that I am not overly worked up that there is a general issue her yet or not. We do have two data points, but that is it so far. I am just trying to think the issue through in terms of warranties, extended warranties, the things that we are doing that could potentially invalidate our warranties, and so forth.

As I see it, if this does turn out to be a serious design/manufacturing issue, then it would start showing up a lot and result in a general recall. In that case, it would not really matter if we are out of our warranty period or if we have done something to invalidate our warranty. Obviously those folks that run into a problem before the trend/recall is recognized might get the short end of the stick, but even they might have some recourse if the problem that they had to pay to get fixed ends up getting declared a recall item.

This is completely my naivete speaking, so I may very well be all wet.

With that said, does anyone have any experience with recurring issues getting handled as a recall by Kawasaki or any other major manufacturer?

Thanks,
Chris

RE: The KACR on the KLX250S
 

My only experience with recalls has been with Harley with my front master cylinder. Once a manufactor determines there is a problem and issues a recall or bulletin on the issue their pretty good about it. The Trick is to get them to See there Is a Problem and issue the recall/bulletin in the first place. That's where you will have problems getting something fixed.



LV

RE: The KACR on the KLX250S
 

I may be way out in left field but isn't our motor a regeared 250 from the no longer produced Mojave quad? Those were around for a heckuva long time and from my old atv mags the motor sounds very similar if not identical. I would imagine that if it was the Mojave would have had the KACR as well and I haven't ever heard of them having the same problem.

RE: The KACR on the KLX250S
 

Nope, there is no resemblence between the motor in our KLX250 and the Mojave. There is a very striking resemblence to the motor in the Mojave and the KLR250 however. Matter of fact, it is basically the same motor. That motor uses adjustable rocker arms, not shim under bucket to do valve adjustment. Actually, the KLR250 is nothing more than a single cylinder from the Concours, which is the de-tuned motor from the Ninja 1000 of the 80's. Kawasaki has a long time history of "make-froms" and uses it all the time.

The KLE500 (not sold in the US), Ninja 500 and Vulcan 500 LTD all use the exact same motor and tranny.

Most of the single cylinder 4 stroke engines have a very similar KACR mechanism. When the motor is running - above 1000 rpms or so, the weights are spread and do not activate the compression release. This makes it easy to start the engine when hot.

A friend of mine that works for Schnitz Racing has removed the KACR from his KLR650 and says the bike has never run better. I finally had a chance to contact him this weekend and asked him about the KACR on the KLX250. He asked me a question - he is always getting you to think for yourself - "How about putting a pin between the bob weights so they will never close?" This way you can try running without the KACR to see if there are any adverse effects. Then when you find out the bike runs just fine and there is no more noise from that area, just remove the weights and be done with it.

As soon as I get the time to play, I'll be modifying my KACR to see if we can have a nice simple fix for this problem.

BTW, other Kawasaki 4 stroke singles are also having some "issues" with this device.

I'm just trying to make our bikes so bullet-proof that deej will wear out his plastic by cleaning it and still having the bike running just fine!

RE: The KACR on the KLX250S
 

Marty for president :)

Im interested, maybe in the dark days of this winter I'll be able to perform this mod. Things that break are not my friend.

RE: The KACR on the KLX250S
 

Marty,

Did you ever get any info from the folks on the KLR640.net site about the KACR. I am more interested than ever with the news of sullydirt and EMS's recent woes.

Also, I was thinking today about adding the optional kickstart to my bike. Would it be advisable to maybe remove the KACR and add the kickstart to aid in hot-starts? I don't know if a kickstart is any better or worse at starting a hot engine than an electric ignition. Just a thought.

RE: The KACR on the KLX250S
 

I was wondering something similar - without the KACR, and if the compression is a bit too high for electric start without it, would a kickstart help? I.e., press the red button and kick at the same time - together that might be enough to overcome the need for the KACR, electric assist ;).

But right now I'm biting my nails waiting on EMS's and Sullydirt's shop reports - depending on that, it may be time to stategize, or not.