Absolutely new. Any advice?

H_e_LLBOY

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I recently received as a gift a 1980 kz750 and would like to convert it to electric. As I'll be mostly totting around in the city, it's my understanding that a hub motor will be less than ideal, so another type will be needed. I'd ideally want top speed to be around 70mph on the highway. Any recommendations for a motor capable of this? I understand I will need to have a sprocket made as well as gears that will accommodate the torque of the motor. Or is there a source for them somewhere online? What would be the ideal gearing? And as far as battery goes, perhaps a 100 mile range at first. Is there a good source for these batteries? From my understanding Lithium Phosphate is a good choice, although obviously I don't really have a clue which is best. What type of controller and throttle/braking will I need? I truly appreciate any assistance you could provide, and fully understand if you can't. Any question I didn't ask is due to ignorance, so feel free to answer questions unasked if you feel it would help me accomplish this conversion. Thanks, and have a wonderful day.
 
First and foremost, heavy costs more. You're going to need that weight capacity for enough batteries to have 100 mile range (and it will probably be a squeeze all the same), if you can sacrifice that then you can reduce weight (and cost) significantly. A hub motor would be well worth considering imo, usually I'm dead against all that unsprung weight but hardly any 80's bikes handled worth a damn anyway and the simplicity is a huge plus.

I'm building a similar weight bike at the mo and a QS138/90 would be capable of the specs you're looking for and will pull like a train at low speeds but quickly run out of steam, underpowered for highways and overtaking. Their 8kw hubs would probably work very well and the 8kw midmount could probably make something impressive if their 3kw mid motors are anything to go by.

As far as I know Zero motorcycles offer a kit that would probably work really well, no idea of the details but if you're in the US it might be a good tried and tested option.
 
For the 8kw midmount motor from QS, how would I go about the gearing? Would I need industrial grade to handle that amount of torque? And would that motor need a larger cooling fan to keep from overheating?
 
H_e_LLBOY said:
For the 8kw midmount motor from QS, how would I go about the gearing? Would I need industrial grade to handle that amount of torque? And would that motor need a larger cooling fan to keep from overheating?
No worries about heat from the motor, the 3kw runs cool at 15-20kw. Controllers shouldn't be a big heat issue either but I've no idea on the options, sevcons are a ballache but do whatever you want, china does serious bang per buck but forgets things like manuals and variable regen. Belt reduction primary worked out really simple here but the pulley on the 8kw seems to be the same as the 3kw and the small motor can push that belt size beyond its limits, might be a weak point.
 
Also put this in the general not the build threads pls. So annoying having to go through newb questions in the wrong sections,i mean it does clearly say :roll:
 
You might want to look at this (and similar) threads working out some of the details of things like amount of battery needed, etc:
https://endless-sphere.com/forums/viewtopic.php?f=10&t=114610

Your exact details will be different, but this one has similar speed and range needs, and should help guide you to list what details you need to know about your intent, usage, etc., to figure out what you need to get to accomplish your goals. :)
 
speedy1984 said:
Also put this in the general not the build threads pls. So annoying having to go through newb questions in the wrong sections,i mean it does clearly say :roll:

Looks like a build thread to me, in that he's figuring out what to use to build his bike with. :? I'd say it's in the right section if he continues his build in it once he's got his parts (at that point he can edit the thread title to reflect that). ;)

(if it were me I'd actually have titled the thread with the kind of bike, "conversion", and then the rest of what it already is....)
 
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