so slow and boring...

[farmbob]

Hi.
I want to build an electric cart that will only go .5 to 3 mph. Total cart weight about 500 lbs including "driver" and run on level or near level ground.

It would be great to get some suggestions as to ideal motor types and sources for an application like this. All the motors I have looked at so far have way too many rpms!

Thanks.

 

[anickode]

.5 mph?

How bout a clock motor?

Mobility scooter. Hands down. Find an old one and gut it. You'll have the right motor, gearing, controller, probably even some salvageable steering components, a comfy seat, maybe some good batteries, and an on-board charger.

 

[sikbrik]

Agree with mobility scooter, 100%.

 

[Functional Artist]

Yup, a mobility scooter is a good place to look.

IMO, For a 500lb. kart to be reliable & last a while your gonna want a "beefy" motor.

A 48VDC 1,000W motor geared "way down" ~10:1 would go really slow & never ever work hard.
or
I've also seen a few gear reduction motors at Alfa Wheels

Like, this one is 36V 650W with a built in 6:1 gear ratio. (~500 RPM)
...less than $100.00 delivered

https://www.ebay.com/itm/Motor-w-CO...m=162582832024&_trksid=p2047675.c100005.m1851

 

[itsid]

3mph top speed 500 lbs..
I'd say 350W is all you'll need in the end (properly geared of course)
A bit too lazy to do the math
but you can do it yourself .. you'll find all you need in the essence thread pinned to the top of this forum.

from my guts.. 350'ish Watts

'sid

 

[farmbob]

Ok! So a mobility scooter is just a watered down wheelchair...
I live out in the country, so not a lot of stuff like that around but I'll keep looking and one will probably turn up.
In the meantime I may just get that motor Func. A showed on eBay so that I can start building.
Even 500 rpm sounds like a lot. I imagine that's the top speed though and I can use gears to bring the speed to the range I want.
I'm looking forward to digging into the big resource of info here on the forum to do it right.

Thanks for the replies!

 

[itsid]

... I imagine that's the top speed though and I can use gears to bring the speed to the range I want....

No, not you CAN... you MUST!

ungeared motors like these typically run at least 3000 rpm or thereabouts.
That must be geared down to your desired top speed and according to motorpower and moved mass of course

Of course you could run the motor at a slower rate with a controller,
BUT that would still not move whatever you need to be moved.

the gearing is essential to even have enough torque to move

'sid

 

[farmbob]

So this little beast is only 350 W 24V but with a 9.7:1 gear reduction.
https://www.ebay.com/itm/350W-DC-El...wJ:sc:FedExHomeDelivery!84627!US!-1:rk:2:pf:0
It only has about half the HP and torque that the one mentioned by Func. A has. So the RPM would be about 300?
thanks for the input and info so far.

 

[J.S.@SMS]

If you cant find any mobility scooters and you live in the US, try checking craigslist under motorcycles. It's weird but they tend to be found there along with other things that aren't motorcycles. For example, during a 2 page 5 minute search in the motorcycles category I found 6 mobility scooters, 4 electric scooters, 2 go karts, a golf cart and a hover board.

 

[ian928]

I used a complete axle from a Mobility Scooter to power my sons Pedal Car. I think it is around 20:1 gear reduction. Something like this:

https://www.ebay.com/itm/DRIVE-DAYS...h=item2ab44c60a8:g:S2oAAOSwbVdbjQLZ:rk:9:pf:0

Of course, it could be cheaper and easier to get a complete mobility scooter with controller and all you need.

 

[Laura]

https://www.instructables.com/id/Gas-Beating-Electric-Race-Kart/

Slow and Boring. Try this on for size.

I drove several races in an indoor kart facility where the karts were all electric. A rush. Not boring. Great acceleration and as fast as you wanted to go on that track.