[Nemeii]

I would like to build an EV bike.

I am a skilled mechanic with access to many venues as well as parts and tools for fabrication.

The range I'm hoping to get is really my least concern. Minimal 20-30miles max would be satisfactory. If we can get more then all the better.

The level of performance *I am hoping to get* is a minimum equivalent to a 220hp ICE engine, preferably high revving (10k-14k RPM's). I understand that electric motors, especially DC are renown for their torque. But please do not make under-power recommendations for my my goals. Basically, what are some motors that are relatively close to the value of the ICE engine power I want (+/- 10%). It's hard for me to say as Ive seen people claiming that the hp isnt a direct conversion due to inherent torque delivery differences in each form of locomotion.

As I am under the impression that DC motors are more torquey - I find myself leaning heavily in the AC direction. As most can deduce a sudden burst of torque will throw the bike into a wheelie. This is not my goal. I am thinking a max weight of 800lbs overall (+/-10% - the bike, motor, battery and controller, etc.) which should help with any wheelie problems however I still need to fairly accurately control the motor speed. Needless to say, I'm not a fan of road rash.

How much money?
Well lets put it this way - Im not a Bimmer driver from Croatia (but props to his EV bimmer build, amazing; in concept and cost.)

Simply put, I wont put a fortune into new parts. I mean I could but the more you spend the less enjoyable the outcome is. Id rather put more work into the final project than money. But I wont mind if you offer some realistic numbers as to what to expect to spend or even a range to help me decide. From questionable quality to good, used, or even new quality.

This being said, in case your all wondering, I do have a background in electronics. Unfortunately it's almost all analog experience. I do have Logic gate experience as well as some in building amplifiers (no, not installing car audio - give me some credit.) and other simple digital devices and micro-controllers. So, sure I could pille up a bunch of dry cells from autozone with a huge frankenstein style potentiometer, or some high power transistor - mount it to a bike frame and putt about getting absurdly poor performance and even more absurd looks. But that's not what I really want to do.

I'm looking for 4 main things.
Value, used parts I am ok with - but this is not a junkyard build, no hoopdi
Simplicity, even if it requires me fabricating things, this I Excel at.
Control, an accurate motor controller I can rely on, but not made of gold.
Power, 220hp equivalent - crazy torque not required.
Coherence, the bike needs to flow, no quirks or regular issues. I want this to be a thorough build.

All the rest such as looks and mounting will be directly resultant of the drivetrain and its components. This is not a concern for right now. After all - form follows function.

If anyone has the knowledge and experience to see where I should be headed and with what - it will be greatly appreciated. Ive had this idea eating away at my imagination for some time now and its time to bring it to life.

I will continue pouring through the incredible wealth and volume of information on the DIY wiki pages, and hopefully I will hear back from people. Thanks ahead of time, and props to this sweet forum.

[Anaerin]

Perhaps the motorcycle hubmotor(s) made by the fine folks over at endless-sphere might do the trick: http://endless-sphere.com/forums/vie...hp?f=10&t=7718 is the creation thread, and you can buy them from http://www.enertrac.net/

[TX_Dj]

Don't mistake ICE HP (peak, nearly unusable) with Electric HP (continuous rating).

To get the "feel of a 220HP ICE" you are saying you want torque at lower RPMs. That's what a DC motor gives you.

Have you seen killacycle? http://www.killacycle.com

It uses two modified motors rated at 25 HP (continuous, in stock form) to pull 7-ish second 1/4 miles in excess of 170 MPH.

Torque is what does work. Horsepower is the measure of how much work can be done per unit time. Horsepower doesn't exist without torque.

I.E. if your ICE produces torque peak around 3700 RPM, and lets say that peak is 100 ft-lbs, then your HP at 3700 RPM (not ICE peak HP) = 70 HP. If your EV motor produces 300 ft-lbs at 1500 RPM, then your HP at 1500 RPM = 85 HP, i.e. you hit the horsepower a lot quicker, the more torque you have at lower RPMs.

Use the torque, luke!

[Nemeii]

TX_Dj - i think you just blew my mind, excuse me while I change a fuse.

So yes, I definitely have seen the killacycle.

Im looking for something more moddest. Though im completely stupified when you say that the motors they used were 25hp continuous and Unmodified. I would be happy with a bike capable of a 9-9.6 second quarter mile.

I think I understand what you mean about torque, and because its a bike application I dont mind having less torque as long as I can get higher rpm's. does that make sense? I think that will make it less wheelie prone.... if I am not mistaken.

So all this said, I should probably go with DC then (honestly I feel like this is much easier to handle anyway)

Does anyone sell a simple DC progressive controller?
Any idea's on cheap batteries? (cheap as in inexpensive, not crappy)

Smaller charge is fine. Like I previously mentioned 20-30mile range is good for putzing around depending on how hard I push the motors(s) obviously it would go down or up.

Does anyone have any input on DC motors they recommend over others in the 25-40hp continuous range?

I was considering a hub mount, however in light of initial development simplicity I can do chain drive. Either way 1550+ rpms @ 1:1 ratio to the tire drive sprocket is what im shooting for.