suggested gear ratios

[Bruceb]

Was wondering if anyone can give me a suggested gear ratio for this years bot at full weight running 2 cims that will give the wheels 10 fps? I know I can calculate the unloaded ratio using 5200 as the cim rpm but I don't know how to figure the rpm loss due to bot weight.
Thanks
Bruce

[Kit Gerhart]

Originally Posted by Bruceb

Was wondering if anyone can give me a suggested gear ratio for this years bot at full weight running 2 cims that will give the wheels 10 fps? I know I can calculate the unloaded ratio using 5200 as the cim rpm but I don't know how to figure the rpm loss due to bot weight.
Thanks
Bruce

Bot weight is only a factor while accelerating, or while spinning wheels in a pushing match. To calculate speed you would attain after the wheels quit spinning on the slick surface while accelerating, you shouldn't be far off by basing your calculations on 4500-5000 rpm.

[Joe Finkel]

I think is going to be important to have a low gear for initial acceleration.
And by the way,how many teams are planning to use AM 2-speed shifters.

[Kit Gerhart]

Originally Posted by Joe Finkel

I think is going to be important to have a low gear for initial acceleration.
And by the way,how many teams are planning to use AM 2-speed shifters.

With the very low traction we'll have, there is no reason to have low gearing for low speed acceleration. Even with much higher gearing than we normally use on carpet, we will have the power to spin wheels uncontrollably. The trick will be to have a subtle touch on the throttle. Also, having a good traction control system should be very helpful.