Hi all,

New here and have a few problems with my 2007 KLX 250.

I have been playing around lately with the front sprockets and after putting a new front sprocket on the other day I put it all back together and wanted to make sure it ran all nice and smooth so with the bike still on the stand and the back wheel off the ground I put it into first and the chain started jerking. I have absolutely no idea why. Apparently I am not the only person because the bloke in this youtube video link had the same drama.

This video is not my bike, but is the exact same problem I am having.


What am I doing wrong and how do I fix it. Thanks in advance.

Sull

 

My knee-jerk reaction is that there's no resistance to regulate the tension on the chain, when your bike is on the stand. Do you also get (as much) chain slap when you're riding it? Are you using a roller tensioner or any kind of hard nylon "slap pads" to smooth things out?

BTW, welcome to the forums!

 

Well I thought it may be chain tension as well, so I tensioned it up a notch, and even though there was a slight decrease in the amount of slap, it was still there. And that was with a higher tanesion that what I normally ride with.

Previously when i have had the bike in gear on the stand it has not done this, so something is certainly amiss. The bike does slap a little when I am riding it, but not much.

I looked at the rear sprocket and It is defeinately showing signs of wear, and I specualte that this may be a contributor, but how is this so? Can any one shed any light on why a worn rear sprocket would cause slap of the chain?

Im not using a roller tensioner as far as I know, I have never seen "slap pads" what do they look like?

Sull

 

Do you have a service manual on your ride yet? Use that number, then when the suspension is loaded, there will be less slap. Have you hit up the klx section yet? I think that there was something related to this same question. Welcome to KF

 

This is what I was referring to as a "chain slap pad." It mounts around the swingarm pivot. I don't know if there is a Kaw-specific application or not. The product looks like a good idea, to me.

Swingarm Chain Sliders : TM Designworks, Online Store

You could also fabricate your own chain tension roller; essentially two side plates, center nylon or rubber rolling usually spindle-shaped wheel, and mount (on bottom; not top) so that when your swingarm is unloaded and the chain has the most slack, it will help interrupt the slack harmonic causing your slap. These were fairly common back on the '70s moto-x'ers. (...as opposed to the chain guide rollers placed immediately in front of the incoming chain/rear sprocket, common on late model bikes.)