Chain slack measurment

[Fred T]

Hey gang, my son's KDX was bought used and we don't have a owners manual. Can you tell me the chain slack measurment please. Those snail tensioners make a big change in each adjustment so I just want to make sure it's not too tight. It has to be real loose on my KTM. Thanks! :thumb:

 

[Twiztid One]

my 2001 says 55 to 65 mm or 2.2 to 2.6 inches , measure at the back of the swingarm slipper {guide}.

 

[Fred T]

my 2001 says 55 to 65 mm or 2.2 to 2.6 inches , measure at the back of the swingarm slipper {guide}.

Thanks. :thumb:

 

[canyncarvr]

Yep. 2 1/4" at the back of the slipper.

That's a kickstand measurement I recall? NOT unloaded (suspension).

 

[Smit-Dog]

And even after adjusting while on the kickstand, doesn't hurt to stand the bike up, put some weight on the rear to get the rear axle centerline the farthest point from the swingarm pivot, and re-check chain slack.

 

[Braahp]

my 2001 says 55 to 65 mm or 2.2 to 2.6 inches , measure at the back of the swingarm slipper {guide}.

Which is exactly 3 fingers. :)

 

[Smit-Dog]

Whose fingers? XRPred's or Dirty ~D~'s?

:think:

 

[cicone]

Which is exactly 3 fingers. :)

I wish you were my urologist :laugh:

 

[BRush]

I've always been in the better-too-loose, than too-tight school of thought. I use a small wooden dowl with two marks on it as a go / no-go gauge so I don't have to remember what the specs are.

 

[23jayhawk]

Well, well, well - look who's back in the KDX family!

 

[Jaybird]

Like Smit-dog said, put the swingarm in a straight line between the front shaft and the rear. This will be the tightest the chain can get. At this point you want to have about 1-3% of the distance between shafts as chain slack.

24" shaft centers would mean 2% of that is .48"
When the chain is in it's tightest point, you should be able to move the chain up and down a total of .48"
Do this once, then put it on the stand or kickstand, or whatever situation you normally would check it...then make a guage like Brush does and always check it by that from then on. Keeping a good eye on chain stretch will help to keep you chains and sprockets around longer.

For correct chain span:
distance A-B x 1-3% = distance S-S

 

[Fred T]

Yep.

Well, well, well - look who's back in the KDX family!

Well, as head mechanic here I godda bone up on the KDX wrenchin' cause it's been a couple years since I did any work on a green bike. I 'm excited for him because this will be a real nice bike for him.

 

[23jayhawk]

I recently made the same decision for my son - he grew so fast that he shot past the KX100 size. After looking at a bunch of bikes I finally realized you can't beat a KDX for a first real dirt bike. :thumb: