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Old 16-03-2010
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Quote:
Originally Posted by ianjoyner View Post
Okay so in helping me understands the trade offs between different setups:

Take the truggy 4 cell starting point. Why not just get the 2000kv and gear up if you want to go faster or gear down if you want more torque. What is the advantages of going up to the 2250kv or down to the 1700kv? Assuming you want more or less speed respectively. Thanks.

It took me a bit to get my head round this, it really is a battery/motor combo with a sweet spot of around 30,000rpm

With my limited understanding of it all now this is how I see it.

Higher the voltage (ie cell count of the battery) the more efficient the system will be giving longer run times and cooler temps.
So if you go for a 6S (6 cells = 22.2volts) battery you need to match that to the right kv motor.
Motor kv x voltage = RPM's so to get 30,000 from 6S you need a 1400kv motor.. Simply going up and down motor kv's with the same batterys will put you above and below the efficeint range of the motor

Truggys also require a larger sized motor (longer usualy).

Another thing I didnt really twig for a bit was a larger battery cell count does not equal more weight its down to the mah rating. A 6S 2500mah lipo is approx half (dont pick me up) the weight of a 3S 5000mah lipo


Hope that helps
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