48v 2000w e scooter motor as mid drive

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alix47   100 mW

100 mW
Posts: 43
Joined: Oct 24 2014 8:20am

Will this 48v 2000w motor work as a mid drive

Post by alix47 » Jul 11 2018 1:18pm

I want to know if this motor will work as a mid drive it's a 48v 2000w electric scooter/ go kart
motor weight about 3 kg 4000rpm that's all i know about it. I added a pic thanks in advance
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dustNbone   10 kW

10 kW
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Location: Vancouver, BC

Re: 48v 2000w e scooter motor as mid drive

Post by dustNbone » Jul 11 2018 1:34pm

Of course it will work, that's literally what it's designed for. Do the math on motor RPM vs desired wheel RPM (speed) and apply the appropriate gearing, you've got yourself a mid drive.

alix47   100 mW

100 mW
Posts: 43
Joined: Oct 24 2014 8:20am

Re: 48v 2000w e scooter motor as mid drive

Post by alix47 » Jul 11 2018 1:42pm

Thanks for the reply do I need to gear it down because I seen few with no gearing they just use the bike gears

markz   100 GW

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Joined: Jan 09 2014 11:38pm
Location: Alberta Canada

Re: Will this 48v 2000w motor work as a mid drive

Post by markz » Jul 11 2018 11:13pm

For sure it will work as a mid drive.
You said 4000rpm, well that will have to be decreased a lot, by a factor of 10 or so.
You will have to add a gear reduction. How many teeth does the motor gear have?
Lets say its like 14T, you will have to add two stages. 14T to 72T = 5.24:1 which will get it down to 763rpm. But you still need more reduction. 26" wheel 328rpm is 41kph. Which you need to half. 14T to 72T-14T to 28T = 381rpm.


How will you mount it?
- Should be easy. I just converted my hub motor to a mid drive. I just had to triple check that everything was level, that the gear on the motor lined up. Chain line was good. Make an adapter for the disc mount on the motor to convert it to a fixed gear, then spin the motor in the right direction. Just view my most recent posts, "Weekend Project". Sure its hillbilly style but I wanted the silence that a direct drive motor has, rather then the loud geared Cyclone motor I already have. I have been riding it today and it rides good. A few fixes need to be done but its a good cruiser.

Are you going to use the Cyclone crank freewheel, bb and crankset?
- If you are keeping your rig, I'd go for the heavy duty freewheel. Then figure out your gearing ratio's.
viewtopic.php?f=2&t=89877&p=1386574&hil ... g#p1333440
You simply put in the motor parameters, and then set your wheel diameter to include the effective gearing. So if your motor has a 10:1 reduction to the crankset, and then your chain goes from say 42T on the front to 16T on the rear, spinning a 24" diameter wheel, you would put in for your wheel diameter:
24" * 1/10 * 42/16 = 6.3"
To simulate a different gearing you just change your wheel size accordingly.
http://www.ebikes.ca/tools/simulator.html
alix47 wrote:
Jul 11 2018 1:18pm
I want to know if this motor will work as a mid drive it's a 48v 2000w electric scooter/ go kart
motor weight about 3 kg 4000rpm that's all i know about it. I added a pic thanks in advance

nfmisso   10 mW

10 mW
Posts: 21
Joined: Jul 09 2018 5:36pm

Re: 48v 2000w e scooter motor as mid drive

Post by nfmisso » Jul 12 2018 6:41pm

yes, you have to gear it down.

Typical person pedals in the 60 to 90 rpm range, which is then geared up (most bikes) with a typical road bike having about 4:1 ratio, so in top gear the rear wheel is going 240-360 rpm for about 30 mph.

If you drive a wheel directly with the motor, you need about a 1:15 ratio (somewhere between 1:10 and 1:20 will probably be okay).

If you want to send it to the crank for a mid-drive, you'll need an additional 1:4 step down to approximately match your pedal rpm.

alix47   100 mW

100 mW
Posts: 43
Joined: Oct 24 2014 8:20am

Re: Will this 48v 2000w motor work as a mid drive

Post by alix47 » Jul 19 2018 11:56am

I have to wait to for the motor to arrive got sent a damaged one will receive new one tomorrow and made the freewheel myself with help off YouTube it's 42t and 52t for the pedals and motor has 11t but will set it up tomorrow and see which setup works best, plus thinking of using a go kart auto gearbox, the motor will be just behind the back tyre till I get a longer bb so I can mount it under the bb shell so it don't hit the pedals and will update with pics in a few days

alix47   100 mW

100 mW
Posts: 43
Joined: Oct 24 2014 8:20am

Re: 48v 2000w e scooter motor as mid drive

Post by alix47 » Jul 19 2018 12:02pm

Thanks for your reply just waiting for the motor to test it for the best setup will update with pics in a few days

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