Sprocket Tips 101 Help

[JustinBoots]

Can anyone tell me the effects of changing a rear sprocket from a 32 tooth to a 34 tooth? My son's bike is a DRR50cc with very few mods (Ignition, exhaust, clutch, etc). Advice I got from one person was that more teeth on the sprocket would give a better hole shot, but rob from the top end. That seems the opposite of how I think with tire sizing since the larger the tire, the more torque it takes to spin it over.

[joe0718]

He is correct. A 32 tooth rear will have more top end than a 34 tooth rear which would give you more bottem end.

[JustinBoots]

Great! Thanks for confirming so quickly. Guess I'll keep the 34-tooth on there for the time being until he is more comfortable with the top-end range.

[EthansDad]

joe is right. my $.02 on a mostly stock 50 is to keep as close to 19/35 for final gearing as you can. I've experimented with dropping the ratio one tooth at a time down to a 30T rear, but the little motor just does not like it. what ends up happening is you do HAVE more top speed available with something like a 19/32T, but your RPMS drop since the motor has to work harder and you end up with the same top speed as 19/35, just with less grunt out of the corners.

all around, I like the 19/35T combo on a stock 50, and its also much better suited for beginning riders since they will make up more time coming out of the corners.

-EA

[JustinBoots]

Thank you very much for the info. You guys are GREAT!