2000 KX250 gearing

[commandman15]

I have some questions about gearing my KX250. I see a few differnt materials that sprockets are made out of and I want to know pros and cons of those. My bike came from the previous owner with the front sprocket sprocketed down one tooth. He said he did this too add some torque I believe. I liek the way the power comes on the bike but wouldnt mind just a tad bit more power instead of speed. I am gonna buy a new front and rear sprocket so am wondering if I should go back to the stock 13 tooth front and get a certain size rear sprocket to get the same effect without being so hard on the chain. I dont know that much so If you could help me out that would be great. Thanks

 

[Camstyn]

Stock gearing was 13/49, what is the rear on yours now?
If he dropped the front to a 12 and left a 49 on the back it should have already drastically lowered top speed and made it pull harder in every gear. Keep in mind that for every tooth you take off of the front, it is almost the equivalent of adding 3 teeth to the rear. If your gearing is 12/49 now and you want it lower yet, but with a 13t front, try a 13/53 or 13/54 combo.

As for material, all fronts are made of case hardened steel, so you can't go wrong there. With the rear you have your choice of steel or aluminum (and cromoly, stainless steel etc. in some obscurities)

Steel lasts longer then aluminum, but weighs more. It is debatable whether or not you can actually feel the difference. The reason you would is that because it is rotating mass, it has a lot more affect than if you added the extra pound to the swingarm.. Similar to adding weight to the flywheel, it takes longer to get the rear wheel spinning because there is more weight to accelerate. If that makes any sense.

 

[GhostRider32]

I went from 13-49 to 12-51 and love it. All I do is trail ride so it works out great fo me It is still plenty fast but with way more power where you want it for trail riding.

 

[commandman15]

Hey thanks a lot guys. I just checked my gearing and it is it 13-50 so the guy I bought it from is a lyer. I counted it a few times. I like this gearing but wouldnt mind it a little more trails friendly. But not too much. Give me some opinions. You guys have been a great help

 

[Someone]

They usually stamp the tooth count on the sprockets. FYI.

 

[OKKX'er]

13/50 is my favorite ratio, if you add more teeth to the back, you will lower speed and thus multiply engine power slightly more. Don't forget to order a longer chain.

 

[commandman15]

Well I may go to a 51 tooth rear to add a little more power. I dont mind losing the top speed as long as it isnt too much. I like how it is so I dont wanan change it too much does that mean a need a longer chain?

 

[Camstyn]

Depends on how much room you have on the axle adjusters. You should just be able to move the axle forward a bit.

 

[commandman15]

Will moving up to a 51 be a big differnce? thanks

 

[MarkSims]

Moving from a 50 to a 51 should be noticeable - but not a big difference.

 

[commandman15]

I guess Im gonna go with 13-50 and get steel prockets. My manuel suggests getting a DID 520DM 114-Link chain. I have no idea what size the previous chain was but I guess I am only adding a tooth to the rear so its not to far off. Does that mean I shud stay with the factory recommned size or get another link?

 

[Camstyn]

Standard should work fine.

FWIW chains usually come in a length of 120 links and you shorten them yourself. Try 116 first and if it's too long, shorten it to 114.

 

[DWreck]

Standard should work fine.

FWIW chains usually come in a length of 120 links and you shorten them yourself. Try 116 first and if it's too long, shorten it to 114.

I agree. You can always shorten it if its too long but if you cut it too short......well :bang: