Anyone know where I can find a 38 tooth rear sprocket. Already running a 15 tooth up front. Bike pulls hard enough with the 15 so I think I can go one more tooth to get a better top speed.

 

sf oem 39 is the smallest that fits and already touching the guards...also, smallest listed i found was the 39t for the klx250....

you can go remove the chain saver and go with a 16t front and replace the rear with a 41t rear...that should be just about the same...

16t front sprocket http://www.ebay.com/itm/JT-Front-Spr...-/330908180963

41t rear sprocket DRC Dura Sprocket SKU: D34-24-041 https://www.wheelingcyclesupply.com/cart (only steel rear sprocket i found that makes a 40t and 41t for the klx250)

 

Sprocket | Chain | Motorcycles Sprocket | ATV Sprocket

They have them, I had them make me a TI in 38 tooth. One tough sprocket!

 

so the 38t fits without grinding down to your swing arm?...even with a 13t/39t setting..i was grinding down my chain guard a lot...

 

I have no issue on my 07?

The can guide on the bottom, or guard up top? I have a Zeta chain guard off a DRZ 400.

 

the top...i see your chain is literally just resting on it...guess it's okay if you haven't had any issues...good to know...

 

No, you're right to be concerned with this. Most of the OEM sliders are too soft for more aggressive chain contact caused by sprocket changes. However, a better aftermarket guide/slider usually alleviates this. They seem to be much more durable. I'm not personally familiar with how this particular sprocket change for the SF will work out in this case, but you're definitely right in considering guide/slider wear in any case.

 

I have an 06 250s and ive been running a 15/42 and i have to take the case saver off to run the 15 . There is barley any more room on mine . not enough to run a 16. Maybe the older bikes are different then the newer ones??

 

I can run my case saver with the 15 Tooth on my '06. I wonder what's different?

 

Interesting thought. The part numbers for that engine cover are different from '09 and later, but I can't tell why. And there could be a minor difference in chain alignment between generations, but that's less likely.

Edit: Well, I did a bigger search and found the '07 and '09 are the same number, but the '12 is different.