DIY electric minibike project

Hi guys complete noob here other than recently delving in quadcopters I don't have much experience and was wondering if anyone knows the feasibility of building this little bike, doesn't need a massive range or much top speed

Its one of these junker chinese minimoto frames


And I have two of these motors my dad picked up somewhere a while a go, brushed 24v 7amp 156rpm





The sprocket that came off the original engine is a very close size to the motors spindle but not sure on the best way to mount it at the spindle is very short..
The front sprocket is 11t the rear is 55t and the wheels are 12"


Also I'm not entirely sure on the motors rpm, is 156 rpm too slow? would i have to run stupid sprocket sizes? or could i up the voltage to the motor for higher rpm..?



Im not sure what this is, it was attached to the opposite end, is it a brake mechanism or something? Im guessing its not needed..

As i said im a complete noob but if anyone can help recommend a cheap brushed esc controller with some means of adding a throttle it would be great.

I was thinking of running it off 2x 14.8v 10000mah lipos in series or would 30v / 33v fully charged be too much?
If not would 2x 11.1v 10000mah in series be better 22.2v / 25.2v fully charged be better?

Thanks for looking any general advice appreciated and if this is a stupid idea please let me know!

If the only thing you're asking is feasibility, then I say sure, but I'm scratching my head at what you're starting with and how hard it will really be.

First off, that motor. If it is only 156 rpm at 24v sounds like your bike will have a top speed of maybe 115 feet per minute. 1.3 miles per hour, at least with that gear ratio and that wheel. Let's have some fun with this:

The rear wheel will turn 31.2 times a minute at 156rpm. 12" wheel might be 14" tread diameter, x 3.141592, let's call that 44" per revolution of the wheel, or 3 2/3rds feet. Does 114.4 feet per minute sound good to you? In 60 minutes that's 6,864 feet, a good 1.3 miles per hour. How many miles can you walk in an hour?

At 200 watts if you swap the sprockets around you top 30mph IF you somehow belabor all the way up to that speed. The point I'm making is that motor won't work out for you. Assuming the bottom picture is your speed control, if you replace it with one that would run 48v at 500w, assuming that's viable, it's still a painfully slow bike.

I assume you're familiar with these, but in case you're not, here's what I think you're picturing when you're done. http://www.razor.com/products/dirt/mx650/ But here's what you're planning for. http://www.razor.com/products/dirt/rx200/

So let me tip you off on a cheap donor with possibly all the parts you'll need. I was about to start building a trail bike this way a few weeks ago when somebody stole my bike cruiser for it. You can find these at below 500w but don't bother with them. There's 500w, 650w, 750w, 1000w. Either 24v or 36v, depending on which you find. There's a motor, controller, wiring, switch, controller, etc. Maybe the batteries still work for a little while. Get on Craigslist, depending on the batteries and overall condition, you can get those for $50-$100. Try to avoid the one with the gearbox, but if that's all you can find it's usable. The Currie motor will run close to 3,000 rpm.

I can't say if the sprockets/chain from the Currie will be compatible with what you have, but I'm guessing no. Probably a little issue to resolve. There'll be a little work to do, you need a mount for that motor, etc. But it's a good project. The Razor MX500 or MX650 can be found under $100 needing batteries, maybe a little work. Options to consider.

http://orangecounty.craigslist.org/bik/5662605848.html