Jump to content

Sprocket sizes

Recommended Posts

I have a 2012 sx125 and I need new sprockets and chain. Should I get a 13 front and 50 back? Or 13 front and 51 back? I do a lot of trail riding but will start riding on a track in the next few days cause my buddy is almost finished up with his motocross track.

Share this post


Link to post
Share on other sites

standard is 13/50 i doubt you will even notice the difference between 13/50 and 13/51

it goes from 3.85:1 ratio to 3.92:1 ratio , but in saying that i would go 13/51 to help it out of the corners and tighter trails

Share this post


Link to post
Share on other sites
Umm, 13/45 will give you 75mph easy:
25464_371305100802_4936935_n.jpg?oh=4e40ea84143cecc72d2566720a1d2dd0%26oe=59957531
It all depends on what you want to do with it. Do you like what you had, or want taller or lower? 

What do you think would be best for track riding?

Share this post


Link to post
Share on other sites
1 hour ago, carlcrist said:


What do you think would be best for track riding?

Typically tracks are slower than the real world, but each one varies and most experts will change sprockets for each track, depending on top speeds and finding the right gear to get out of difficult turns. Quite frankly, if you have never run the track before, I'd run what you've got and see how it works. Based on that, you will know if you need more grunt or more speed.

Front sprockets are easy to change and only require a chain adjustment. Buy 12/13/14 tooth sprockets and experiment. 

Edited by sbest
  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:


×