chain chattering

[mtice]

I've have a new KTM LC4 640. Although the chain is adjusted per description in the manual (looks loose to me), it's chattering under lower revs / higher torque in each gear. Once the engine speed comes up in each gear, it quites down. Any suggestions?

 

[agitt73]

my 200 exc dose the same thing

 

[Anssi]

Perfectly normal at least in the present racing models (SX, EXC, MXC).

 

[Jaybird]

Take a good look at your alignment. Also look at your chain guide and see if there is any wear on one side or the other.
You are probably ok. My little 125 makes a bit of noise with a quality chain and sprockets where as it makes less noise with a junky chain.
(close tolerences does this) Now, I can't hear squat from the chain when I'm running. I can only tell you about the difference in sound when its off and I'm pushing it.
One thing I will say is, on a bike that doesn't experience jumps, you can afford to run your chain just a tad tighter. But if you have perfect alignment, I wouldn't worry about it.
You could take off the shock and suspend the rear to the tightest point. Adjust the chain then until you have about 1/2" of travel both ways. Remount your shock, set the bike on the ground and then see where the chain is for future reference. It will probably be a bit tighter than the manual states at this point, but you should be fine with it.