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Discussion Starter #21
I haven't checked in recently and wow - lots of replies.

1. Yes torque is more sensible number for choosing the trans - so my 15hp at 3000rpm would be 26lbft. So lets say the trans is for peak 40 lbft.

2. Many reasonable rpm electric motors do produce high torque from zero rpm up. For this reason many electric sales people claim that somehow electric hp is more than gas produced. Of course the shaft doesn't care what makes it spin. However many e-motors' power is limited by the heat they can take. A motor that is rated 8hp at 300A can possibly give 10hp at 400A for limited amount of time. The HP numbers usually are constant rated so in acceleration for example you could get more out of them.

3. While E-motors have flat torque curves still the HP is result of rpm*torque so the motor produces more power at higher rpm. Thus gearing would be handy.

4. I know bike transmissions are not planetary. I was more hoping that someone would say something like: "Oh concretemixerX/poop flingerY/Motorized NutcrackerZ has the exact transmission you are looking for.

5. CVT belt setup comes up the most and I guess it would be the simplest and most flexible. I am not so sure the efficiency is quite up there compared to real trans. Again planetary would be sweet as locked to higher gear there would be no gear to gear power transfer at all.
 

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Reading through what your looking to do, a snowmobile clutch and jack shaft setup would be the direction I'd be looking into. The clutch can be tuned with counter weights to match your motor output, they are available for cheap money from any snowmobile salvage yard and there are plenty of off-the-shelf performance parts that you can purchase to fine tune to your requirements. I've seen tons of snowmobile engines tucked into MC frames for drag racing applications so it should not be a huge leap converting an electric motor with this set up into a MC frame.
 

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quote:Originally posted by mlinder

quote:Originally posted by Ratty-550

quote:Originally posted by mlinder

Again, torque and HP are different ways of expressing the same thing. HP at a given RPM is always the same torque, and vice-versa.
Right, but gas v. electric they devolop their power much differently.

On equipment that can be ran either/or the easy rule of thumb is double the electric hp for a gas engine. i.e. 10hp electric = 20hp gas
:(

That's like saying 10 gallons of water is the same as 20 gallons of paint thinner...

Horsepower is horsepower. Please don't think I'm trying to come off as a dick, I'm not. But measurements are measurements. They don't change depending on what you are measuring. A cubic foot is a cubic foot, regardless of what's occupying that space.

The issue that's run into with electric motors is that the torque curve over RPM is flat and available instantly, which is completely different than internal combustion engines, which can be hard on attached machinery.
Exactly, why didn't you say all that in the first place? :D
 
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