Hello from NorCal SoOR

Just acquired a thoroughly-used 2002 long-back. Will be converting it to “rough terrain” yard vehicle. It won’t need high speed but it will need torque, ground clearance, and traction.

I’m looking forward to learning a lot here. Thanks in advance.

Torque motor I can hook you up. Traction is terrible.
You will need to add a rear axle from a golf cart.

There is almost no traction for hauling or pulling on terrain other than hard surfaces on a GEM.

This is due to its front wheel. drive design. The weight is all on the rear wheels. Get a rear drive cart.

That’s disappointing but makes sense. Is adding a golf cart rear and speed matching it to the GEM’s axle even feasible?

Alternatively, has anyone EV swapped a Kawasaki Mule 3010 4x4? That would be optimal. The metalwork would be easy for me but I don’t know anything about building EVs.The mule uses a 16HP ICE connected to the drive train via a toothed drive belt. In theory an easy swap but the “I don’t know anything about building EVs” has me stumped.

Yeah. Cant remember his screen name, rockcrusher, rock crawler, something like that. I bought some parts from him and he told me the story.

He got a 10.35:1 golf cart rear or maybe he used a gem front diff, anyway, identical gear ratios, motors, and tires. Took two T2 controllers programmed identical, one to each motor, hooked the harnesses up in parallel. Had switches for front wheel drive, rear wherl drive and awd. Ran a lithium battery pack.

Essentially he sort of built a polaris ranger ev out of a late 02.

This sounds like a better project than making a 2002 GEM Offroad capable. The only virtue of the GEM is the possibility of running it on the road.

Pull the Mule engine. Make a 2 bearing support for the Mule drive pully with the proper spline on 1 end and a plate to mount the Gem Motor. Then transfer the the GEM electrical parts to the Mule. And find a place to mount the batteries. Switch to lithium batteries ASAP with a little extra Voltage to make the GEM motor and controller Happy.

Could work, but a 48 volt system from a golf cart might be an easier/cheaper electric package in the long run. Though a 96 volt AC motor would be best. Once you have the belt drive sorted for mounting electric motors changing from 1 system to another would be mechanically easy. You did not say if your GEM is 100% functional.

Complicating the “rough terrain” concept is the rear suspension on Gen1 2002 Cars. Normally, the entire moving component is one piece swing arm design attached at 3 pivot points at the frame. I call this the swinging gate.

For level ground operation this action is fine. Probably marginal on rolling turf in a golf course application. But for Rough terrain there is the potential for unequal weight on the wheels. When one wheel falls into a hole or up on a mound the weaght offset is translated to the forward and opposite corner and load/unload the opposite wheel. Same thing happens when you try and drive a forklift diagonally up a driveway. For those that have never driven a forklift, this is easily demonstrated by lifting a sheet of plywood by one corner.

This is not to say people haven’t ever driven their cars on anything other than perfectly level ground. It is a well known issue and should be part of your regular inspection to dive under the back of your car and inspect your trailing arm for cracks (especially as a new owner). The fix ranges from welding it up again (sometimes with additional gussets) and keep an eye on it to happen again.

Or, you could modify the plan a bit and put in some rubber bushings and ALLOW it to pivot around a bit. Oddly enough, that is what the engineers started to do in Gen2, and Gen3 cars. Go figure.

Thank you all for your input. We have given up on the “rough terrain” idea for the GEM and now just plan “gravel road” between house and work shop.

Thank you for the picture. I checked ours and no cracks, there…

Unfortunately the top shock mount brackets are ALL cracked.

Sigh. I wish I were better at TIG welding.