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Unread 05-06-2013, 12:41
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Re: JVN's Calculator (help)

Quote:
Originally Posted by Ether View Post
Sure.

In an earlier post you said:


In low gear your top speed is slower, so the forces and torques at full throttle are lower compared to high gear at full throttle.


I agree with this statement. However, lower torque is not the only factor contributing to loss of efficiency at higher speeds. We found that our effective gearbox spread was lower than 2, while the theoretical spread was 2.27. In my opinion, additional loss of speed should be taken into serious account when designing multi-speed drivetrains; this applies to JVN's calculator in particular, since it is so widely used. It allows for a "gearbox efficiency" number on top of a "speed loss constant" -- but neither of these numbers are anywhere close to being actual constants.
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