Electric Motors

Joined
Jul 7, 2019
Messages
3
Does anybody have a reliable source for electric motors? For example, you pulled out that 2,000 watt motor for the Yard Mule Brad. Pulled from where? Maybe used forklifts or stock pickers? Golf carts? Where might the best place to start looking?
 

Radical Brad

Garage Hacker!
Staff member
Joined
Mar 13, 1999
Messages
5,675
Location
Kakabeka Falls, Ontario, Canada
Greets!
The Yard Mule uses a 20,000 watt motor!
A 2000 watt motor would be good for a fast electric bike or scooter.

If you can discuss your design goals a bit more, I can help find you some sources.
Here is a bit of text from the Yard Mule plan I am currently writing...

Electric Motors and Controllers

Everything about an electric drive appeals to me over a petrol engine with the exception of cost. A good electric motor and controller will certainly cost you $1000 or more, plus the $500 cost of a pair of large deep cycle batteries. Having said that, my design goals included not paying $10,000 for an ATV, as well not making a lot of noise, so an electric drive fits this bill perfectly.

Electric motors are typically rated in watts, but as a comparison, 750 watts is equal to one horsepower, so you will want an electric motor capable of at least 3000 watts, or beyond 10,000 watts for some serious hauling capacity. The motor shown in the photo is a PMG-132 permanent magnet DC motor, and will happily put out 4 HP all day, with short burst of up to 20 HP for a few minutes at a time. At 24 volts (2 batteries), the shaft rotational speed of this motor will reach around 1700 RPM. I paid $1000 for this motor, and it is very well built.

When looking for an electric motor, a good source will be online companies that sell parts for converting gas vehicles into electric. Many of these companies will offer motor and controller combinations and all of the wiring you require, so you can get up and running easily. Take some time to research these amazing online sources of information and get familiar with the options available. You will be looking for the same size range of motor that many are using to convert motorcycles into electric vehicles.

Earlier in this plan, I discussed my motor controller, which is the small blue box that takes battery power and sends it to the motor based on the throttle position. Mine is an Alltrax MPX-4834 golf cart controller and is capable of 300 amps continuous with 400 amps peak. The simple rule is to get a controller that is larger (in amps) than the total capacity of your motor.

You do not have to be an electronics expert to wire a motor controller, as it has very few connections, usually just battery input, motor output, and throttle.

3536

Here is the label on my PMG-132 motor...

3537

Brad
 
Joined
Jul 7, 2019
Messages
3
Thanks all, I looked into Luna and Golden as well as others and although I am beginning to understand the options. I think my problem now is to narrow down the options by refining and sharing what I am trying to do.

I am currently building a Timberwolf trke. I live in the country south of Ottawa, On. Canada. I have recently had a stroke that did two things, it causes balance issues and cost me my driver's license. I have a 25km drive each week for physio and was thinking that the Timberwolf would resolve the balance issues (who says you don't forget how to ride a bike) There are a few hills on this ride as well as gravel roads. I would prefer to pedal but I also have to accept that there are times when I can't. Therefore I am looking for an electric motor that would help get up some of these hills and gravel roads.

Another project that I am looking at wistfully is Brad's Yard Mule. I don't think I need something that big but I am thinking of something similar but based on the rear end of a lawn tractor with a platform you could stand on and have a trailer hitch that can haul my trailers around my hilly property. I need something that can travel off-road, sort of like an Electric Walker.

Bottom line is, for the Timberwolf, do I need a front-wheel-drive? Mid-engine? and what size? I am looking more for range than speed.

For the Yard Mule Jr. my thought is to salvage the rear end from an 18hp MTD tractor to use as the rear wheels with a platform to stand on to make an all-terrain vehicle that I can go up and over the berms and stuff that makes my property.
 

Radical Brad

Garage Hacker!
Staff member
Joined
Mar 13, 1999
Messages
5,675
Location
Kakabeka Falls, Ontario, Canada
For the TimberWolf, a front hubmotor would be perfect.
Never use aluminum front forks or suspension forks with a hubmotor, but other than that... anything goes.

Worked amazing on my other Wolf...

3581

Brad
 
Joined
Jul 7, 2019
Messages
3
No suspension forks period? How come? Now I have to go find a standard fork.
 

Radical Brad

Garage Hacker!
Staff member
Joined
Mar 13, 1999
Messages
5,675
Location
Kakabeka Falls, Ontario, Canada
Suspension forks are aluminum, and aluminum is not your friend when it comes to any hubmotor.
My face was rudely introduced to the pavement when I refused to believe this once...

3584

Even at only 300 watts, the motor tore the aluminum forks apart after one day.
These were brand new quality forks from a decent mountain bike (rock shox or something like that)...

3585

Aluminum does not fail nicely at all. I consider it like glass.

If you are like me and prefer to learn by trial and error, then please let me suggest the following...

  • When going over the handlebars, lean slightly and tuck your head down while entering a roll position.
  • Expect that the bike will remain in motion during your impact, further adding to the carnage.
  • Once the dust settles, stand up quickly and pretend like... it ain't no big thing! Examine wounds at home.
That is my routine as an official AZ test pilot!

Brad
 
Joined
Sep 12, 2012
Messages
2,440
Location
Apple Valley, California, USA
Suspension forks are aluminum, and aluminum is not your friend when it comes to any hubmotor.
My face was rudely introduced to the pavement when I refused to believe this once...

View attachment 3584

Even at only 300 watts, the motor tore the aluminum forks apart after one day.
These were brand new quality forks from a decent mountain bike (rock shox or something like that)...

View attachment 3585

Aluminum does not fail nicely at all. I consider it like glass.

If you are like me and prefer to learn by trial and error, then please let me suggest the following...

  • When going over the handlebars, lean slightly and tuck your head down while entering a roll position.
  • Expect that the bike will remain in motion during your impact, further adding to the carnage.
  • Once the dust settles, stand up quickly and pretend like... it ain't no big thing! Examine wounds at home.
That is my routine as an official AZ test pilot!

Brad
Thanks for the laugh, Brad

Also, for bringing back memories of my own motorcycle 'mishap', against a 3 ' brick wall.
 
Top