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View Full Version : an idea for reverse,, maybe


jarcynvicnchris93
01-26-2009, 03:42 AM
Well some of you know I was looking for a way to get reverse on my kart and even considering the expensive Comet Reverse Gearbox. Well I finally decided to copy ryf and use a riding mower transmission. but while doing research I ran across a racing kart using a starter motor for reversing the kart. I think the starter motor they referred to in the article was maybe a standard car starter that Kibble wrote about on here for use on a electric go kart. Could this work for reversing a kart?? I know electric motors have allot of torque but would one be enough torque for say reversing a off road kart??? or would they just be limited to street karts?? just trying to think outside the box. I personally would like to be able to back my kart up without having to get out and push.. call me lazy if you want hahaha...

Jared

ed1380
01-26-2009, 10:53 AM
Ive seen a video on youtube of a guy that sells off road go karts and thats what he uses

kibble
01-26-2009, 11:16 AM
*cough* Lazy *cough*

You would need a high amperage switch such as a contactor for the motor. Unless you leave the solenoid intact, might be able to use that as well. Well, if you don't modify the motor at all, and just leave it as is, you would only need a 12V relay from a car and a switch to hit reverse with.

modelengineer
01-26-2009, 02:24 PM
Apparently you should rewire the starter motor if you want to do this.
Some people with Edge buggies use electric reverse.

Why not use the leg of an outboard motor? They have a forward-neutral-reverse gearbox in them, and they are dirt cheap.
I've seen it done and that's how I would do it. As a bonus (maybe...) you end up with a motor which has the crankshaft forward-back rather than side-side. You could make a front engined, rear wheel drive kart.

Kenny_McCormic
01-27-2009, 02:20 PM
Why not use the leg of an outboard motor? They have a forward-neutral-reverse gearbox in them, and they are dirt cheap.

Maybe in the middle of the desert! Even in central Michigan outboards are worth their weight in gold, like more than some entire inboard boats.

jarcynvicnchris93
01-27-2009, 05:47 PM
modelengineer wrote-"Apparently you should rewire the starter motor if you want to do this.
Some people with Edge buggies use electric reverse."

well I thought about that and the I realized that the reason why people are rewiring their starters is so they can go foward and reverse. I just want to reverse mine with the flip of a switch. The switch part is what is throwing me. Im wondering if I need a special switch or controller or if just a regular toggle would work. It seems like Kibble or someone said do not use a toggle. Is there a certain type of controller I could buy off the shelf that would work???

kibble
01-27-2009, 05:51 PM
modelengineer wrote-"Apparently you should rewire the starter motor if you want to do this.
Some people with Edge buggies use electric reverse."

well I thought about that and the I realized that the reason why people are rewiring their starters is so they can go foward and reverse. I just want to reverse mine with the flip of a switch. The switch part is what is throwing me. Im wondering if I need a special switch or controller or if just a regular toggle would work. It seems like Kibble or someone said do not use a toggle. Is there a certain type of controller I could buy off the shelf that would work???

I'll draw you up a schematic in which we'll use the solenoid already built into the starter.

MDMike
01-27-2009, 05:56 PM
an ole fashion push button, would be good. Constant 12 power to starter, switched 12 power from switch to solenoid, like on a chevy starter.

kibble
01-27-2009, 06:20 PM
I just want to reverse mine with the flip of a switch. The switch part is what is throwing me. Im wondering if I need a special switch or controller or if just a regular toggle would work.

Wait a minute, are you talking about making the motor reversible or just making the kart go in reverse when you hit the toggle? If you're just talking about making the kart go in reverse, there's no need to modify the starter or use a controller.

kibble
01-27-2009, 06:36 PM
Here's a quick diagram I drew up. The contact on the rear of the solenoid is the one that has the nut and goes to the battery directly.

The drawing on the left is just using a toggle. Most automotive toggles can probably take the amperage that the coil from the solenoid draws. The one on the right, I used a push button with an additional relay, reason being that I've noticed that many push buttons now days are built rather cheaply and may fuse together or damage the contacts when a high amperage goes through them. The relay basically isolates the low power section from the high power section. If you use the relay method, you can place the relay near the starter and then run some thinner cable to the push button.

jarcynvicnchris93
01-27-2009, 06:39 PM
man Kibble you always seem to save the day man. Sorry I stepped away for a bit to feed my kiddos dinner. Yeah I just want to go in reverse not both ways. Thanks all you guys for jumping in quickly to help me out.

jarcynvicnchris93
01-27-2009, 06:41 PM
yep your right just make the kart go in reverse not the starter. thanks again guys

modelengineer
01-27-2009, 06:47 PM
You just need a switch which connects power to the starter solenoid, and wire the solenoid up same as in a car.

They re-wire them for more torque because they are pushing a 450kg buggy backwards. They are also geared down HEAPS.

jarcynvicnchris93
01-27-2009, 06:55 PM
You just need a switch which connects power to the starter solenoid, and wire the solenoid up same as in a car.

They re-wire them for more torque because they are pushing a 450kg buggy backwards. They are also geared down HEAPS.


then maybe I do need to rewire one because my buggy is heavy. and I weigh ovr 250lbs. So I think I may need to rewire and gear down. Does anyone know where to get instructions for gearing down?? Does the rewiring really have anything to do with Torque???

modelengineer
01-27-2009, 07:00 PM
You probably don't need to rewire it, just gear it down a lot. THEN if it doesn't work you can rewire it.

jarcynvicnchris93
01-27-2009, 07:03 PM
You probably don't need to rewire it, just gear it down a lot. THEN if it doesn't work you can rewire it.

thanks Andrew, well you guys all have a good one. Im going to bed cuz I have been up for two days straight and now I am exhausted.

Peace out,
Jared

porsche930dude
01-28-2009, 05:35 PM
somthing like this http://www.oldminibikes.com/forum/more-than-two-wheels/10399-cvt-help-please.html