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suicideneil
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Join Date: Feb 2007
Location: Devon, England
01.03.2011, 03:41 PM

Quote:
..i dont see how that efficiency is logic. would it be 'top speed' instead of efficiency ? it may mean that 3 % of speed become 3% of torque or vice versa, as thats all a rollout is ?
The 1:1 rollout ratio is just a good guideline to try and prevent beginners from entering unrealistic numbers in order to create a speed machine from unsuitable components. More advanced users will know that they can use a taller overall gear ratio if their motor, esc and batteries are suitable, but some young people who are new to the hobby usually make their post something like "how do I make my truck do 100mph?"; if you dont give them guidlines to follow, then they will only end up cooking somethign expensive without ever figuring out why. 1:1 is close to what most stock trucks have, such as your esavage and the brushed emaxx for example.

Quote:
but, speed/torque is 'defined' by the motor ? if one slaps a torqier motor on, gears less in drivetrain, the rollout is eventually changed. so using briang's calculator my rollout now is 1.8:1, i dont see how that can be 'inefficient'.
Bear in mind the thread on rcu is 5 years old- there are simpler equations to follow these days- or just use the gearing calculator, saves the effort.

As I mentioned before, when you use a more powerful motor, esc and batteries, you can ofcourse gear higher and this causes the roll out ratio to stray away from the 1:1 ratio which is optimum for a lower powered stock setup. Its not so much about there being an inefficient rollout ratio, its more to do with being efficient for a certain setup; a sensible 40mph setup will be much closer to 1:1 vs a speed-run setup which is geared for 70mph for example.

I wouldnt get too bogged down worrying about rollout ratios, its more important to get an understanding of which esc, motor ,battery & gearing combos are best for any given scenareo & vehcile; years of reading and research helps with that, like 'learning on the job' at your work place..
   
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