Torque and Max Speed

[fjmartin]

While cruising through this forum I've seen a lot of folks talking and doing changes to the front and rear gearing on the bike by replacing the 14T with a 13T and sometimes changing the rear of the bike to a 45T or 46 from the stock 44T. I found a website that shows the impact to speed and torque by making these changes along with what you will have to do with a chain. Pretty nice!
http://sprocketcalculator.com/

[Weldangrind]

Cool topic; thanks for the link.


It makes sense, since theoretically, you have more torque-carrying ability with lower gears. Old drag racers will tell you that a change to a car that increases trap speed is an increase in HP, while a decrease in ET is an increase in torque.

[RedHawk47]

I believe that there have been posts that state that when they put a 13t on their RX3 that they got a higher top speed (which is counter intuitive).

This can happen because the RX3's relatively low power vs. the air resistance/drag does not allow max rpm before the drag exceeds the power available. By replacing the 14t with a 13t the engine is higher on the power curve when it reaches the 14t max speed and can go a few more mph before maxing out.

[bogieboy]

us kawasaki ke100 owneres see the same thing... drop your front from astock 15 down to a 13 and you gain 4-5 mph due to the engine actually being able to pull the gear instead of lugging it...

[fjmartin]

That would be really cool and maybe would offset the fact that I'm also doing a 45 on the rear. Can't wait to try it out but I'm waiting to change the cogs until I pull the wheels to change from the OEM rubber to the Shinko 244's I have for more offroad rides.