electric off-road kart

[jmauld]

I'm getting started on a small yard kart for my son. My goal is to have it be able to run 15-20mph and have enough torque to run decent sized tires for driving on some paths that we have in the woods.

I'm going to be basing it off of the "itzy bitzy" plans from spidercarts.com. The design specifies a single wheel drive system. Since he's going to use it off-road, I want to have 2wd. I will probably go with a live axle, but I would also consider using two independent motors.

I was thinking about sourcing parts from an on-road scooter that is designed to carry an adult.

Do you guys have any words of wisdom for me? Do you have any recommendations for websites to purchase scooter parts? Do the scooters use the motor to brake, or will I need a separate braking system?

 

[dpaxson]

if you're looking for torque, those scooter motors are probably going to be disappointing. they're pretty small. i don't think you're going to be going anywhere off road at 20 mph with scooter motors. but to answer your second question, you would need a separate braking system

 

[KieranM]

have a look at a few sinclair motors, they are used in robotics. wheel chair motors are good too if they are geared correct.

 

[jmauld]

Any idea how much power will be needed to get 15mph (in the dirt) out of a small kart with a 50 lb boy on it?

 

[dpaxson]

i would say around 1500w but that's a rough guess. it's 670watts/hp i think so that's like 2 ish hp. gearing it for 15 should give you decent torque

 

[oscaryu1]

1500W would flip you upright. I have a 900W motor on a little scooter of mine, from a dead stop, it'll climb things up to 45 degrees... that is, if i can stay on it.

And I weight 160+...

Get a nice 750W+ and gear it low (say a 70/80 rear sprocket) and you should be good to go...

 

[jmauld]

Do you guys have any suggestions for a gas pedal? There are a few pedals listed on the scooter websites, but they are all sold out of them.

 

[redsox985]

Not exactly the best place to put your question.

 

[r97]

imnot completely shure it would work but how about rigging a pedal up to a dimmer switch

 

[fowler]

they piss power out aparenty (very inefishant)
well thats what i rekomended a will ago and this is what i was told
u can buy speed controlers
or u can pull one from a scooter

 

[jmauld]

This is the one i was planning on using when I was researching this build, but it seems to be sold out everywhere now.

http://www.monsterscooterparts.com/acpeasje.html

I've seen a few electric karts using handlebars instead of a steering wheel. Anyone have experience with that setup? Seems like it would be odd to drive.

 

[r97]

make shure that that pedal is an actual acelerator pedal not just an on/off switch, also doesent that minimo jeep or what ever have hand acelerator and hand brake on butterfly steering wheel? handlebars may be different feel and look but should be fine unless you have a rack and pinion. you could try hooking up an electric scooter throttel to a normal pedal