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gear questionratio
- Thread starter randall
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Wide = Gear ratios are further apart
Standard = average differences
Close = Gear ratios are closer together
So... gear ratio is a number that defines how often one gear turns in relation to the other gear in the mesh. If you had a pinion (the input gear I'll call it) with 25 teeth and a spur (I'll call that the output gear) with 100 teeth. To get your ratio you always divide the output by the input. GR=O/I
100teeth / 25teeth = 4
The gear ratio here is 4.0. The input (pinion) turns 4 times while the ouput (spur) turns once.
In a multi speed transmission each gear (1st, 2nd, etc.) produces a different gear ratio. How close each of these ratios is relative to each other is how you end up with close or wide ratios. When the ratios are wide the transmission will stay in each gear longer and force the engine to pull more rpms before the transmission will shift to the next gear. Because a nitro engine does not really provide consistant power throught it's entire rpm range there is a drawback here as the power to the transmission will fluctuate more. The advantage of a wide ratio tranny is that you can cover more ground as far as acceleration and top speed are concerned.
In a closer ratio setup the gear ratios of each gear are more similar so even though you gain more speed when going up in gear it's not as significant of a speed increase as a wide ratio tranny. Now because the ratios are closer the engine will stay in a tighter rpm range thus less power fluctuation is seen. This creates more consistant power and although the vehicle will not accelerate as well from a dead stop or have as much top speed as a wide ratio setup, it will be smoother and gain speed more consistantly throughout the entire speed range.
In my opinion wide ratio is more fun if you're just having fun but close or standard would be more beneficial in a race setting.
Standard = average differences
Close = Gear ratios are closer together
So... gear ratio is a number that defines how often one gear turns in relation to the other gear in the mesh. If you had a pinion (the input gear I'll call it) with 25 teeth and a spur (I'll call that the output gear) with 100 teeth. To get your ratio you always divide the output by the input. GR=O/I
100teeth / 25teeth = 4
The gear ratio here is 4.0. The input (pinion) turns 4 times while the ouput (spur) turns once.
In a multi speed transmission each gear (1st, 2nd, etc.) produces a different gear ratio. How close each of these ratios is relative to each other is how you end up with close or wide ratios. When the ratios are wide the transmission will stay in each gear longer and force the engine to pull more rpms before the transmission will shift to the next gear. Because a nitro engine does not really provide consistant power throught it's entire rpm range there is a drawback here as the power to the transmission will fluctuate more. The advantage of a wide ratio tranny is that you can cover more ground as far as acceleration and top speed are concerned.
In a closer ratio setup the gear ratios of each gear are more similar so even though you gain more speed when going up in gear it's not as significant of a speed increase as a wide ratio tranny. Now because the ratios are closer the engine will stay in a tighter rpm range thus less power fluctuation is seen. This creates more consistant power and although the vehicle will not accelerate as well from a dead stop or have as much top speed as a wide ratio setup, it will be smoother and gain speed more consistantly throughout the entire speed range.
In my opinion wide ratio is more fun if you're just having fun but close or standard would be more beneficial in a race setting.
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