need help building electric bike!!!!

hello all, i am building an electric bike (basically converting my old bicycle which is useless into an electric one) and figured that no one could be a better help then here at the instructables! ;D anyways, so i am using a 24v 250W motor along with 2x12v 12Ah sealed lead acid connected in parallel (in my country it's almost impossible to find a lipo4 or lipo battery for that matter). i reckon i should be able to get 30kms out of the batteries. so first of all i needed to know if this could work out for me (btw, it's not a hub motor it looks like this:

but, more importantly what i want  to know is that i since i can't find an electric scooter controller over here, would it work if i could connect a electric thumb throttle (or twist throttle) in series between the battery and motor on one side, sort of like u connect a normal fan regulator or switch by cutting either the +ve or -ve wire in half and putting re connecting the wires through the switch, like in the picture below (sorry for the bad diagram), so, thanx in advance, any help will be appreciated and please reply asap as schools are starting and i have to be done before the vacations :P 

Picture of need help building electric bike!!!!
arsi (author) 7 years ago
hey thanks rick, i think rather then using a controller i will use a "bell switch" or the temporary switch..... infact i'll also add in a standard dimmer so that i can control my speed as well! :D thanx! @lemonie' : yeah, series, whats so confusing? it'll give me 24v and around 12Ah...... maybe later (when i have my funds restored :P) i'll add in two more to give me 24ah at 24v,,,,,, for now this should be good enough.... although what i'm really concerned with is if the motor can drive my bicycle (it's quite light) along with 120lbs of pure ME :P @jayefuu' : wait, im checking out ur instructable (as soon as i fix my ipod :P )
lemonie7 years ago

Something not right-sounding in there:
You want the batteries in series to get 24V.
You also need a motor controller (see the links Rick' and Jaye' posted)
I reckon you could get 30 K out of the thing on the level.

Jayefuu7 years ago
There's loads of great info in this guide:
rickharris7 years ago