Electric Go Kart

[nbaffaro]

I’ve been building this the last two years. Thought it’s share it here.
Specs:
1.25 x 0.065 wall tube
1.25 x 0.065 square
Lexan body panels
18x8.50x8 turf tires
3 link front suspension
3/4” rear axle
Pillow block bearings

Motor from a handicap scooter
24v
2 group 24 batteries
Dimension Engineering sygen 50 motor controller

Top speed about 6

 

[landuse]

Very clean looking build! How is that motor holding up? Sometimes those mobility scooter motors can be a bit weak

 

[nbaffaro]

It seems to be holding up just fine. I was going to use smaller batteries but the run time just wasn't there.

It does get hot some but that's only after a very extended use. We live in a very flat area. So we don't have to worry about hills. So that helps a ton.

 

[itsid]

I'm amazed that this thing is powered by a mobility scooter motor as well..

if it gets hot, be sure it doesn't overheat,
since that causes the motor to degrade
(likely permanent magnets which don't like being heated up)

you could gear a hair lower to keep it from overheating if you so desire.

But thanks for sharing this with us.. looks nice
well the color scheme is -uhm- well -uhhhhhm- 'special' let's say
and the coilovers seem to be "just for the looks" right?

'sid

 

[ezcome-ezgo]

That front axle has control arms, I am thinking that it is legitimately suspended on those "springs".

 

[nbaffaro]

It does have front suspension. It is a solid front axle set up. It is a radius arm set up.
I would definitely call them "springs" Any type of spring that I got from a small kids atv were way to stiff. So I came up with these springs.

As for the color scheme the two little girls that this was made for, one wanted it pink and the other wanted it purple. So this was the compromise.

So what is the recommendation for a 24v motor? This motor does have a 32:1 gear reduction on it. Not just the motor. I would like to get it up to about 10mph.

 

[tomead]

So what is the recommendation for a 24v motor? This motor does have a 32:1 gear reduction on it. Not just the motor. I would like to get it up to about 10mph.

I would use a 500-1000 watt DC motor such as a Razor motor. I am modding a Razor Drift cart that had a 250-watt motor which would probably work for some little girls but not so much for bigger kids. These motors would give well over 6 mph so a jack shaft reduction might help with torque to the wheels and keeping them from going too fast.

 

[nbaffaro]

The motor that I have is rated for 1050W at 22.5v

I understand that 1000w at 24v is a lot of amps but I don't have the room for 48v with the current setup.

It's would seem that amps are amps.

 

[itsid]

no nonono..
that's a 230W motor..!

remember that the important value is always the "continuous load" one.
peak can be applied for seconds until it overheats.

And that's likely what happens.

as the firls grow... that peak will get reached quicker and quicker (due to seen heat abuse and added weight of the passengers)
And eventually it will fail!

Yes.. a 1000W motor (like the beloved my1020 PMDC) can get you the 1000W continuous rating (1680W peak)
you'll need to run this thing way more reliably!

maybe a smaller one might do the trick already (750W perhaps)

you can do some math if you know what weight the kart has
here

'sid

 

[nbaffaro]

I understand the difference between continuous power and peak power. For the basis of all of my comparisons with motors I have always believed that the published number is the peak power. So by looking at the 24v 1020my on electricscooterparts.com I see it has a rating of 500w. I believe that would be a 500w peak not a 500w continuous.

If some parts are labeled by peak and other continuous then it is very difficult for someone to compare the two motors.

The idea behind the car isn't so much a go-kart but more of a monster powerwheels. My youngest isn't really capable of driving much faster than 6mph right now.

The long range plan has also been to put a small gas motor on it when the time comes to go faster.

 

[itsid]

well yes and no..

motors that are specifically meant to power a vehicle (scooter, golf cart etc...)
they ideally list both, peak AND continuous rating (as you can see on your mobility scooter motor) but sometimes they only list the continuous rating (since that's the number you need to know)
continuous usually as mechanical output power and peak usually as electrical input power

Unfortunately there are exceptions!

RC motors are usually labelled with peak electrical power only.
(luckily there are exceptions )

Unite motors (the maker of the PMDC my1020 series)
do as they should and label their motors with continuous mechanical power.

When in doubt you need to find the datasheet of the motor, since there's a very important difference between Watts and Watts
Watts as electrical power draw V*A on one end
and Watts as mechanical output power ( Newtonmeter per second)

Conversion losses nowadays are less than 20% in the continuous range
(some are more than 90% efficient even) and towards the peak end of things.. the loss will be 50% or more.

"loss" is converted to heat instead of forward momentum.
And the heat is what's killing you (well the motor that is)

You'll find the specsheet for most good motors online, at least a power diagram that helps you distinguish between electrical and mechanical power as well as peak and cont ratings.

'sid

 

[ian928]

My 4YO have a transaxle from a Mobility Scooter. I am not sure how many watts this motor is, it is adequate for him but not more (the vehicle is much lighter than yours though) The motor is absolutely massive for the power it has, I can not imagine it ever overheating. It was made to drag overweight americans for km’s around shopping malls, it should be Ok for my little one even with the bigger wheels!

How about adding another similar motor on the other side? I would consider direct drive with each Wheel bolted directly on the drive flange. You could Even make a 4WD with 2 motors also on the front!

 

[Tpdingo]

It was made to drag overweight americans for km’s around shopping malls, it should be Ok for my little one even with the bigger wheels!

Lol, and the rest of us are just too lazy to walk. We can't give those motors a break!

 

[ezcome-ezgo]

I refuse to be fat shamed.

 

[ian928]

I am sorry for my comment about overweight people driving Mobility Scooters. It was meant to give a humorous twist to the fact that these motors have to be designed to carry heavy people. The point about americans was because there is few of these here in Norway but they are more common in the US.

 

[itsid]

LOOL

with no word Ian said, that everybody that needs a mobility scooter is fat.

but if you're no elderly or mobility impaired human,
and you still have issues moving your own bodyweight through a shopping mall without a mob scooter.
Chances are you are indeed overweight, no?

'sid

 

[landuse]

I refuse to be fat shamed.

Stand up for your rights. Hahahah!!