So I have a battery pack...

[Michael Foster]

You can go far enough with that. Nice work.

[Daox]

Originally Posted by Nevyn

...

so yeah, we'll call it 15 miles range. I did all the math right, yes?

Yeah, for the most part. I would change your DOD to 50% though. As you get closer to 100%, your voltage drop while accelerating will get you closer and closer to 10.5V/battery. If you drop below that you risk ruining the battery. Therefor, as you get closer to 100% DOD you have less and less power available for acceleration (pull more amps, more voltage drop). Plus, there is a fairly large drop off in usable cycles in lead acid batteries after 50% DOD from the charts I've seen. Not saying you can't take it to 80%, but I wouldn't count on it on a regular basis.

[NiHaoMike]

Originally Posted by Nevyn

So, I posted out to Freecycle in my area looking for treadmills. Got a hit! brought it home, opened it up, and found this:



Paul, Ben, and crew - is it worth anything, as far as go-kart size is concerned?


PERMANENT MAGNET DC MOTOR
Rotation: CW
Enclosure: Open
External Fan
90VDC, 1 HP SCR Controller 6 MPH
115VDC, 1.25 HP PWM Controller 8 MPH

That should work nicely for a hybrid bicycle. Ignore the MPH numbers since it appears to be originally geared for some piece of heavy machinery and you'll want to gear it for a top speed of about 20-30MPH for a hybrid bicycle, more if you want something to race with.