KX450F Gearing on an SX Kit

[Ausm7499]

Just wondering if anybody is running an SX kit on their KX450 and what counter shaft and drive sprocket they are using. I have a feeling their maybe a slight difference between the ST and LT kits vs the SX kit. I can get a 13-17 to fit but it's tight and the tensioner is all the way up. When I say tight I mean using a hook to pull the chain tight enough to get it on the sprocket teeth and then using a c-clamp to hold the chain down to get the mater link in it. I am thinking about getting a 16 tooth to run as a drive sprocket so it's not so tight but that will gear me a little higher to.

 

[Ausm7499]

Well I just checked and evidently the SX kits already come with a 16 tooth for the driver so I guess I will just run what I have. It should loosen up within a couple miles. Would appreciate any input though.

 

[mx4life]

It will loosen up after the first ride. Also the chain becomes looser as the suspension is compressed so having on the tight side is not a bad thing.

 

[retired motoman]

13 tooth after 3 rides

Took off the idler and a 13 fit. It did rub a little on the bottom of the frame until the chain stretched enough to reinstall a used (smaller) idler.
As you found out the 12 tooth CS is too low geared.