New electric motorcycle build - doing homework

Hello my name is Adam. I recently (3 hours ago) finished building my first eBike. (if interested, the build can be found here: http://ecomodder.com/forum/showthread.php/texaselectric-ebike-build-34900.html)

A little background on me... For two years I rode crouch rockets (2002 Kawasaki ZX-6R and 2000 Yamaha R1). They are TONs of fun to ride! Sadly, I haven't had a fun toy like them in 9 years. I am in a different place in my life now (career, money, future plans, etc...) and ready to get back into the activity. I believe electric powered transportation is the future and I am hooked!

I want to build an electric sports bike and I have a few thoughts (i mean demands)...
- 600cc bike chassis (mid 2000's model)
- 120v, 100ah LiFePo4 battery
- 350lbs
- 0-60mph in 3.0 seconds
- 125-150 mile range
- 100mph top speed

I'm basically looking to build a 600cc equivalent (except for range). Slow and steady when I want range, and fast and crazy when I want fast and crazy.

I've done a little bit of research on 0-60/top speed to motor size. But i am unsure... Generally speaking what size motor would I need to propel me from 0-60mph in 3 seconds? Is a 20kw motor enough? (assuming the bike and I weigh 500lbs together).

Any manufacture/model suggestions for air cooled and water cooled electric motors?

What else do I need to consider? (in terms of specs, charging time, etc...)

Thanks in advance for your help!

TexasElectric said:

Is a 20kw motor enough?

Click to expand...

A motor rated for 20kw continuous, maybe. 20kw peak input, no way, at least not with that kind of weight. Unless you're pretty light, your all up weight estimate of 500lbs is probably low, because it will take a big battery for that kind of power and range, and that means a strong heavier frame, suspension and wheels.

I'd suggest starting with a high power ebike rig, something with the performance you want, but not the range. A far lighter high performance rig is quite likely to change your desires, especially when it embarrasses the vast majority of motos off the line, or if they get a good launch definitely when they shift to 2nd gear.

If you're dead set on a full on motorcycle, I'd suggest going and test riding a Zero emoto first.

Welcome Adam.

Agree with John, highly recommend you check out Zero bikes (I'm assuming you're located in Texas by your name? You should update your profile location) as what you're describing is basically a Zero S. While anything is possible, it's highly likely you'll spend a similar amount of money building a bike as you would buying a Zero with these goals in mind.

If you're definitely keen on building your own I suggest you abandon LiFePo4 as you're not likely to hit your weight, performance or range goals with that battery configuration. There are now many better/cheaper/similarly safe options.

What are you actually going to do on this bike? Any amount of highway cruising means that a featherweight build is probably unsuitable, however if you're interested in around town or even offroad performance then best way to get results is to limit the total weight.

Total agree with the above, it depends on how long you have to charge. We converted a Skidoo I know total different but we kept the original weight and added 7 more hp and double the torque and its bloody quick.

We use a HPEV AC 20 26kg at 90 volt battery pack was Calb 72 ah cells they weigh 1.7kg each pack was 6kwh gave a range of 20km on snow, the point was it was on a 3kw charger every time it stopped and charged up in 2 hours from empty.

Maybe go smaller lighter and charge more often otherwise you are really carrying dead weight oh and the more you give it the more regen you get

Cheers Kiwi