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KLX 250sm Cam chain frustration

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Hey guys,

Made a profile to seek any knowledge on a problem I am having. I have a 2009 klx 250SM that I purchased with blown a crank bearing. I rebuilt the engine, new bearings, gaskets and put a BB 351 kit while I was there. Also has bigger TM carb.  There is a new cam chain and a Krieger tensioner I got for it also. It starts and runs well, however im experiencing a lot of cam chain noise. I've adjusted the tensioner in completely tight until the engine dies, it still makes the noise. (I dont have it normally that tight, Just wanted to make sure it wasn't the tension that was making the noise)

I took off the clutch case and inspected, nothing unusual and guides are in place.

I took off valve cover and inspected top end, everything looks normal and made sure valves were in spec.

I have not checked my sub cam chain tensioner - the one under the oil line that looks like I would have to take the pipe off to get to.

At this point, I'm about to buy a new chain, guides and sub tensioner, though I really don't want to. 

 

Here is a video of it running.  You can clearly hear the cam chain rattling away. 

 

The pic below is of the cam guides on the bottom end.

Let me know what you guys think and if anyone else has experienced this. 

 

Mike

 

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Well there is two tensioners for a reason I'd imagine. I'd mess with that before I put another new chain in it. 

But....

Is the chain a kawasaki part?

There's no abnormal wear on any of the chain guides or gears it rides on?

Is it possible the noise is coming from the KACR?

 

I did a quick search on google for you and it seems to be a common problem with that bike. Most people seemed to have fixed it by going to a manual chain tensioner. 

For tensioning cam chain after an engine rebuild I would do it with the side cover off. Turn the engine over from the flywheel bolt, and adjust it during each of the four strokes of the engine cycle. 

Because the cam/timing chain has to overcome the pressure from the valve springs it's going to be tighter and looser at some points during the engine cycle. So keep that in mind as well. 

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I see no need for a manual cam chain adjuster. There are thousands of these bikes running with an OEM adjuster. And only 100's with manual. People could very easily over tighten the chain and cause future problems.

I'd want to see your cam journals and cam. Also do you have the spring in the second adjuster (the one that hold tension on the guides)

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This is why I ask about the KACR. This is on my klr250 but same idea. It made a lot of noise. It was working itself out of the exhaust cam, rubbing on the case. I couldn't see it until I pulled the cam out. 

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I am getting new cam chain guides for it, and sub cam chain tensioner spring. Here are pictures of cams, head and guides.

 

Let me know what you guys think.

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Do you feel any grooves with your fingernails? I don't know if the KACR is working that can cause noise. I would say Brewster knows the most about those. You do have the spring for the plug to keep tension on the guides right? Do you have the guides installed properly?

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The movement of the KACR on your KLR cam is the only one I've ever seen or heard of.  I use a hydraulic press to remove and reposition the KACR's on the KLX's I retime.

Ride on

Brewster  

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