Electric Minibike Conversion

[cargowill]

I am restoring this and converting it to electric as I think it would be a fun winter project. I know I would be better off buying a Super73 or even Radrover or something along those lines….but something draws me to this minibike. I’ve had it forever and would just love a unique project like this. I have an e mountain bike with a TSDZ2 and a cargo bike with an eZee geared hub motor. So I have experienced those types of ebikes and love them as my daily bikes. This would just be something different to cruise around on or maybe even take on some rail trails. I could see maybe building a side car for it as well.

However I am stuck between doing a MY1020 type motor/sprocket combo or doing a dual hub motor set up. I did a list of some pros and cons of each set up below.

This is the sort of hub motor I was thinking.

https://a.aliexpress.com/_mswOw6D

Mid drive Motor
Pros
- Classic looking (keep the original wheels etc.)
- Easy to change gear ratios
- Lots of mounting options
- Many other examples and resources available for this conversion
- Lots of wheel tire combos

Cons
- Nosey chain
- Loss of space for storage and battery
- Loss of efficiency through chain
- Maybe power to cost ratio perhaps not as good
- Have to figure out rear brake upgrade


Hub Motors
Pros
- Clean looking
- Lots of space in the middle for batteries, controllers and storage
- Quiet
- 2wd (lots of weight on the front wheel)
- Regan braking on the front
Cons
- Hub motors don’t look as nice and classic to me…but maybe done right they can
- Less examples of conversions to reference so I have no idea how it will perform
- Weight?

Can anyone add to my Pro and Con list to help me make my decision and get the ball rolling? Or maybe send me in the direction of similar builds?

Thanks!

Pic of bike currently

 

[ZeroEm]

I think any hub motor with any power will be bigger than your current wheel. Don't know how much power 3-4k maybe. You could go mid drive and setup the batteries to fit around the motor.

 

[markz]

Don't do Unite MY#### motor
Here are hub motors that you can mount a tire straight to the hub motor without a rim or spokes.
https://www.leafbike.com/products/e-motorcycle-motor/c-92/
Much less power, some cast - https://www.leafbike.com/products/e-scooter-hub-motor/c-77/page-2.html
https://www.leafbike.com/products/e-bike-hub-motor/14-inch-48v-52v-1000w-front-casted-hub-motor-electric-bike-wheel-1157.html

Mid drive motors - http://www.cyclone-tw.com/motor.html

 

[LeftieBiker]

You could think out of the box - or in this case frame - and mount a mid drive motor about where the rear fender is. maybe even ON the rear fender.

 

[cargowill]

I think any hub motor with any power will be bigger than your current wheel. Don't know how much power 3-4k maybe. You could go mid drive and setup the batteries to fit around the motor.

This hub motor is 13" with the tire and mine is 12" currently, so it would fit pretty perfectly I think. Scooters have huge wheels now. https://www.aliexpress.com/item/33039736678.html?spm=a2g0s.8937460.0.0.3b722e0eGE6ZxJ

 

[cargowill]

Don't do Unite MY#### motor
Here are hub motors that you can mount a tire straight to the hub motor without a rim or spokes.
https://www.leafbike.com/products/e-motorcycle-motor/c-92/
Much less power, some cast - https://www.leafbike.com/products/e-scooter-hub-motor/c-77/page-2.html
https://www.leafbike.com/products/e-bike-hub-motor/14-inch-48v-52v-1000w-front-casted-hub-motor-electric-bike-wheel-1157.html

Mid drive motors - http://www.cyclone-tw.com/motor.html

I like keeping the wheels pretty fat and short, I think the above linked wheels might look a little skinny. I'm kind of going against my usual on this and going form over function.

https://www.aliexpress.com/item/33039736678.html?spm=a2g0s.8937460.0.0.3b722e0eGE6ZxJ

Im leaning toward the above kit. The reason is currently the minibike has no brakes other than a crap drum brake in the back, however with a new sprocket for the mid drive I would lose that. which leaves me with finding wheels with disc mounts. The reason I like the above kit is that for one, I would get regen braking on the front, and I could mount a disc tab to the back....And most of all its a 6" rim, so I could go with minibike tires and the bike would still keep the short wide look.

 

[ZeroEm]

Just wondering if just over 1hp would be enough. The mini bikes when I was a kid was 3.5 -5hp, 2000 - 4000 watts. QS has some nice powerful motors but bigger. Was just thinking that you wanted to keep the looks. I think it is a great project no matter what you decide.

 

[cargowill]

Just wondering if just over 1hp would be enough. The mini bikes when I was a kid was 3.5 -5hp, 2000 - 4000 watts. QS has some nice powerful motors but bigger. Was just thinking that you wanted to keep the looks. I think it is a great project no matter what you decide.

Thats what I'm thinking. The QS motors come in a nice package...it just gets up there in price. I was thinking about maybe getting different controllers for the Hub Motors and putting 60V to them to see if two 1000w motors being overpowered would tick me along at like 40 or so km/h. I feel like any faster would be squirrly.

There is also the hub motors for those 2000W scooters, but they are all 10" which is getting pretty small as the minibike is designed for 12" wheels....might look a little funny.

 

[cargowill]

I just found this...

https://www.aliexpress.com/item/100...earchweb0_0,searchweb201602_,searchweb201603_

Might be pretty decent for what I need...

 

[MorbidlyObeseKoala]

I think the chain and the MY1020 motor keeps that classic look and they come with a mounting bracket already welded on. The chain might be a bit noisier than hubs but I think it would be a touch cheaper too.

I mean is the goal a fun toy or a legit vehicle you need to be as comfortable and reliable as possible to get you short distances? Once you have your battery and controller picked, I think you could swap to hubs down the road if you wanted to try something different.

Assuming your rear sprocket is fixed, you would also still have a regen option for braking. No matter what, it will be fun to see what your end result is, I'm interested to see your battery and controller choice.

 

[ZeroEm]

by cargowill » Oct 27 2020 10:36am

I just found this...

https://www.aliexpress.com/item/1005001 ... web201603_

Might be pretty decent for what I need...

If you get some thing from a scooter with a controller try to find out if you don't need to push it to get it rolling.