12VDC bicycle motor

W

Wizard

New Member
I'm looking for a 12 VDC continuous rated bicycle motor that has been tested to last longer than any other 12 VDC bicycle motor on the market.
 
Completely off topic but it made me think of this....What if you got a 6VDC hub motor for your front wheel, and you ran off a 6v SLA that was recharged by the white wire on a HT motor, then you could have a 2 wheel drive bike for those bad winter days, or for that extra boost up a hill, or you could do it just to say you did.....
 
Thanks for the updates. If anyone finds a 12VDC bicycle motor that has been tested and proven to be a reliable long lasting continuos rated motor...let me know.
 
machiasmort said:
I don't think they make 12V motors for bikes, because the amp draw would be enormous. Thicker wire, voltage drop ect.
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Uhhh, no. If you half the voltage you double the amperage. Volts x watts = amps...that kinda thing. Ohm's law ring a bell? Or is it volts x amps = watts? Or.......zpt

And to the original posters question here....repeat after me.....waste of time!
 
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I don't think they make 12V motors for bikes because there's only so much power you're going to eke out of a 12V motor. I see some people on Youtube who use the 12V starter motors from cars, but I read that those have a tendency to overheat, which sounds less than reliable.
 
I don't know why would you want 12 V motor (is it intended for bike?). However , there are no "tested" motors (that I know of , and I'm pretty well informed about subject) , but you can Google for some manufacturers of industrial equipment (those kind of motors are used as drive motors or servo motors in very big and complicated machines or industrial lines for manufacturing various stuff and they MUST be very reliable and long lasting), or you can order one to be built to meet your specifications (it can be somewhat expensive , well , more expensive than bike motors). Otherwise , you are stuck with automotive industry. Windshield wiper motor or car starter motor (which is pretty useless for longer working periods) or some servo motors (ie electric adjustment of seats or similar ).
If you post a purpose for what you need that kind of motor , we might be able to help you more.
 
scotto- said:
Uhhh, no. If you half the voltage you double the amperage. Volts x watts = amps...that kinda thing. Ohm's law ring a bell? Or is it volts x amps = watts?
Click to expand...

He wasn't being thorough in explaining himself, but it was clear to me. If you run a traction motor at 12V instead of 24, 36, 48 or however many volts, you'll need a lot more amps to make the same power. Since resistive power loss is a function of current squared, that implies much larger, heavier, and more expensive wire to make the harness and interconnects-- when you double the amp load you'll need four times the wire cross-section to have the same resistive losses in the wire. If you don't use the heavy wire, you have to accept significant voltage drops across the harness (with associated heating) when under load.

Likewise, low voltage implies a heavier and more expensive motor and controller for any given amount of output power, because the conductive path must be so much larger.

As for the OP's question-- there is a reason that no electric vehicles larger than kids' riding toys use only 12VDC.

Chalo
 
Chalo said:
He wasn't being thorough in explaining himself, but it was clear to me. If you run a traction motor at 12V instead of 24, 36, 48 or however many volts, you'll need a lot more amps to make the same power. Since resistive power loss is a function of current squared, that implies much larger, heavier, and more expensive wire to make the harness and interconnects-- when you double the amp load you'll need four times the wire cross-section to have the same resistive losses in the wire. If you don't use the heavy wire, you have to accept significant voltage drops across the harness (with associated heating) when under load.

Likewise, low voltage implies a heavier and more expensive motor and controller for any given amount of output power, because the conductive path must be so much larger.

As for the OP's question-- there is a reason that no electric vehicles larger than kids' riding toys use only 12VDC.

Chalo
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And just what is the reason? Anyone? Anyone?laff
 
Urm... for a lil while at least 12v friction drives where not only available - but got surprisingly good reviews;

DXkit_solo_front.jpg

Electric Bike Kit | ZAP! Electric Vehicles

EV buyer's Guide said:
Verdict: "Simple, crude and effective friction drive system"

The basis of the design is a simple, quiet, reliable motor driving straight onto the tyre. Powered by a similarly cheap, reliable lead/acid battery, the Zap (either a complete bike or easily-fitted kit) is a surprisingly good performer, outpacing all other friction drives. There are one or two disadvantages - the friction roller tends to slip in the wet unless you choose the tyre with care, and the roller wears out fairly quickly, although later models are ceramic rather than steel. Otherwise, a great little performer for the price. Out of production for a while, the Zap reappeared, but has now finally bitten the dust, overwhelmed by much cleverer technology from China.

We have tested the Zap kit and Zap/Brompton adaption.
UK Electric Bike Buyer?s Guide - Reviews of the best electric bikes in the UK.
Click to expand...

As a matter of fact the above setup was my introduction to electric, even motorized bikes, a buddy had one kickin' that he wasn't using so I mounted it & a small 33cc[?] rack friction drive to an ol' beach cruiser and used it as a commuter for about a season. Somewhat lackluster - it was a good, slow but steady performer... this was prolly... like 6-8 years ago or so?

Granted, the 'Zap' drive above is now gone, no longer in production - but I did just see something like it for sale by a business very recently in my wanderings, unfortunately I didn't make a note of it at the time other than a nostalgic sigh lol, but if your after a very low cost, mediocre EV - it's out there *shrug*
 
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