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Old 04-27-2013, 11:47 AM   #1
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Default Spur gear question

What the difference in running
74 T Spur & 25T Pinion and
85T Spur & 29t Pinion
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Old 04-29-2013, 11:34 PM   #2
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Some people think more teeth is more efficient, and larger gears will have more flywheel effect. Given the relative size of the gears, I doubt you would notice either. Practically speaking, it slightly alters your weight distribution by moving your motor position. Don't know how that affects off road cars, but the current thinking in pan car is to use the largest gears possible to move the motor as far forward as possible. This decreases the lever effect of the motor on the suspension.
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Old 04-30-2013, 07:27 AM   #3
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Rotating mass is the part of the equation as noted as the flywheel effect by Lonny. It depends on the chassis in question as to the overall effect. A TC4 or other shaft drive car will have a different effect as a TC6 or other belt drive car as the orientation of the gears is 90* different. I would go for smaller on a shaft drive to reduce the effect and keep the motor in towards the center more. You may be limited by the space allotted for the larger pinion in either case.
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Old 04-30-2013, 07:53 AM   #4
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Both really good answers!
Less warning labels... more Darwin!
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and for those that don't know me.. I'm a sarcastic A DBL S
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