cr 125 bottom end power

Hey guys, I've never rode a 125 2t before, but I have my yz250 2t for ramps. I decided I needed a track bike so I went and looked at a cr125 and ended up bringing it home for a great price :thumbsup:. So I've been riding it and it has a 52 tooth sprocket on it so I think I'm gonna go back to stock gearing but wil that help me that much or do I need to do something else to give it more bottom end? I'm gonna repack it and and stuff, but I just feel like it should have a little more. It could just be that I'm used to a 250 2t. Thanks for the input -bryce

Isnt 52 stock? My 03 cr 125 is 52 and when we bought it the guy never said anything about a different sprocket

idk the guy just said it has an oversized sprocket on it and it has a 52...i just assumed stock was 48 but i didnt look it up. mines an 01 by the way

a 48t will give you more top speed less low end .. you can mess with pipes and reeds maybe even the ignition timing but a 125 is designed to get it neck rung out

this will give you and idea

Stock gearing on an 01 is a 13 tooth front and a 52 tooth rear. If you want more bottom end, you would put a larger tooth sprocket on the back, or a smaller tooth sprocket on the front. If you put a 12 tooth sprocket on the front it is the equivelent of going 3 teeth larger on the back. By the way, I have a 53 tooth Ironman sprocket I would be willing to part with for very cheap considering what these things cost new. It has no visible wear on it.

Going down even just 2 down to 50 would make a big difference but it wouldnt be what you want, it would have more top speed and less bottom end. You want a 54 on the back

add a MXBonz pipe spacer

i just read the seizing a 2 stroke thread. def gonna repack it and play with the jetting. i think that should help a ton. thanks again guys

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