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Discussion Starter #1
I've been riding motos since i was 10 and I love to wheelie and was wondering if how much power must a motor produce to wheelie? (relatively low speed start) I'm starting with a supermoto setup that was about 260lbs before removing ice junk, large sticky tires on pavement for good grip. I have gen 2 leaf modules in 10s for 76 volt nominal. people claim all sorts of c ratings for these used modules online but all seem to agree its pleanty, can anyone comment to this?

so far I've been focused on a 5kw bldc motor from golden motors at 72v. I'm afraid it won't be enough power and I'll regret not buying their 10kw bldc.

their controllers for either 5 or 10kw are rated up to 200 amp/ 10kw which as a novice doesn't make sense shouldn't the 10kw controller peak much higher?

I also have found other 5kw controllers rated for 300 amp which were also cheaper. how much can a motor be over amped before problems? I plan on a liquid cooling the motor.

another option I've recently come across are large bldc motors intended for UAV/ "drones" . seems 15-25kw are comparable in price. would these type of motors be suitable for use in a moto? what specs would be important to consider?
 

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It's the torque that is ultimately going to help you wheelie. Power is a function of torque and RPM. It sounds like max RPM doesn't matter, so go with a motor with good torque, and gear it so you have gobs of torque at the lower end. Motors produce all of their torque at 0RPM until a knee (sometimes 2-3kRPM). You want to wheelie? Gear it so all of that RPM range is where you want to wheelie.
 

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Discussion Starter #4
thanks for the reply! my plan woud be direct drive so gearing could easily be played with with sprockets. rethinking the question about drone motors I figured the load would be much different and would require a bearing on the output side maybe.
 

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Drone motors may seem like they are high power, but that HP is at an RPM that's totally useless to you for direct drive (stall) torque.

I could wheelie my parents' 15HP farm tractor; even easier with a plow on the back -- as was said, it's EXCESS torque, over and above what you're making to keep your speed or to accelerate the bike (which it tries to do vs wheelie...a well designed streetbike won't wheelie easily), that will pull the front wheel up. On a bike, that front lift is partly assisted by the front springs and the shock absorber damping rate can keep the wheel on the ground vs let it pull off.

The torque you'll need to start to lift the front wheels is the bike's mass times the distance (keep everything metric to keep it consistent) from the center of gravity to the rear axle.

Now you'll need to add another force, the one that will accelerate the front wheel into the air at a faster rate than the bike itself is accelerating due to torque on the rear wheel. That additional force times the distance you measured adds to the "cg torque" and has to outdo the acceleration of the bikes inertia.

Motorcycle dynamics can be complex, having gobs of extra torque is the easy way out of doing math to 9 decimal places.

Just remember, Mother Nature doesn't make free lunches. A high horsepower small-physical-size motor will make next to nothing for stall torque compared to a slower motor with its HP rates at low RPMs, and multistage gears, chains and belts are a bad way to get there, including that 30:1 belt reduction that's churning in your head.
 

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Discussion Starter #6
I appreciate the beginners wheelie lesson but I've been riding motorcycles over half my life (I'm 26). I think my question got misunderstood. I was trying to ask if you guys think someone who is used to ICE engines will be happy with a 5kw motor. I was afraid of it feeling like a cute bicycle rather than a motorcycle. I ended up buying a 12kw PMAC instead.

As for you 600, instead of asking an electric bike forum the step by step way to wheelie your unknown type of bike, just go out and try. start low and work your way up, you need to learn to control the clutch in a way to dump it without "slamming it" it needs to engage hard and quick but you still need to be able to come off it immediately to prevent yourself from going into low earth orbit.
 

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I'm using a Motenergy ME1003 and 800A Kelly controller for my electric dirt bike built from an old YZ400F chassis. It wheelies effortlessly, but I don't trust the throttle response enough to really sustain the wheelie... this is both a practice and throttle calibration issue that I don't have time or energy to solve. The bikes works perfect for what I use it for which is tooling around and racing an indoor endurocross type event in the winter. I"m running it off of a 2kwh Chevy Volt Module to give you an idea of Voltage (12S), and the bike complete weighs 260lbs.
 
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