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Unread 17-05-2013, 22:48
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Re: Ball Shifter vs other gearbox

Quote:
Originally Posted by DonRotolo View Post
What your mentor is missing are the advantages of having two gear ratios. We generally set our high speed ratio to a slightly faster than usual speed. That leaves our low speed far stronger in pushing power than anything else on the field with a single speed gearbox.

Watch any of our matches. You'll see that we get from one end of the field to the other very quickly but if someone gets in our way we can go right through them in low gear.
I think it's important to be more specific here, since the OP may not fully understand the physics behind drivetrain design.

If you're pushing someone it's not simply because you're geared lower than them. It's because they either have "worse" wheels than you, are not geared to slip their wheels before stalling, or weigh less than you. I suppose you could add in geometry-if your bumpers are at the right height they could end up transferring a bit of their weight onto you, increasing your normal force.

It's certainly possible that someone could be able to push you (or at least stalemate, since you both should be slipping your wheels) with a single speed gearbox, if they had 6 CIM's, an identical base/weight, and were geared to go no more than 50% faster than you.

Quote:
Originally Posted by DonRotolo View Post
Why do you think that cars are coming out with nine speed gearboxes these days?
It's all about fuel efficiency.
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