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A question about the rear sprocket on my GPX

Discussion in 'Technical and Troubleshooting Torque' started by icecoffee71, Jan 19, 2010.

  1. Well, my GPX is due for a new pair of sprockets and chain and I'm considering getting a smaller rear sprocket. My question is, should I? and how many teeth smaller?
    With thanks for your valued input

  2. Obvious question being by changing rear sprocket size you want to gain what?

    Faster Acceleration/Better economy???

    From your post by getting fewer teeth on the rear sprocket will increase the gearing and bike will rev lower than stock but acceleration will be hampered.

    If you feel the need to experiment do so as the modification is easy and not that expensive say $60 for rear sprocket. The other plus for you is that from memory the GPX runs its speedo drive off the front wheel so your speedo will still read right.

    Have fun.
  3. Actually, it was my fiancee who suggested the idea of dropping a cog or two, in order to make the bike run better. He said it would make it run smoother, with faster acceleration than before.
    Though, he did suggest that I check with the "tech-savy" people on Netrider for their opinion on the idea before we committed ourselves.
  4. Ok, so if your not happy with the current acceleration you will need to put on a bigger ie more teeth sprocket on the back not a smaller one. OR you can put a smaller (less teeth) front sprocket on. To get your head around it, if you have a mountain pushy bike or similar look at the sprockets and you will get the idea.

    Now the drawbacks, by lowering the gearing for improved acceleration the bike will rev harder and use more fuel than before plus your top speed will be lowered.

    Like everything in life you get nothing for nothing and its all a compromise. If your happy with it now just leave the sprockets stock sizes. I dont believe it will run smoother because it will be revving harder. From my memory a GPX will already be spinning at about 8000rpm at 100kph.

    Hope I havent confused you and would be interested in others comments.

    Good luck :0)