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crazyjr
RC-Monster Dual Brushless
 
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Join Date: May 2005
Location: georgia
04.05.2009, 11:34 PM

Quote:
Originally Posted by Metallover View Post
I could do that but I'd have to get a couple chain links and the pedals would spin really fast. I might do that if rewinding it proves impractical for the cost.

sabongi - That part is a freewheel and acts as a pinion. Making it bigger would make the gearing even worse.


The gear reductions are - 11/72 to the "spool", 14/32 to the crank, and 48/12 to the wheel in top gear. I want to get about 35 in top gear. The motor is 250kv at the moment and I'm running 24v. That's 6000rpm. The wheel has a 13" radius so 2pi13=81.7 inches/revolution.

I'm not quite sure on my math, but I think I get 1,584 rpm at the wheel so that's... holy sh!t - 180mph!! - Someone check my math...

I figure I will need 1,168rpm at the motor so thats... 49kv.


Is this going to work out or will I need to make some major changes to the gearing?
it's been a while since i was in school, but i thought it was pi X diameter, not 2pi X diameter. if you do single diameter you get 40.82. Still moot point because if everything else is right, you are still looking at 90 mph and still need further reduction or lower kv


Work because i gotta, play because i wanna

People here hate Nitro, I love it. I start it, run it about 50 ft from me and it dies, I go after it. Perfect exercise
   
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