7.5 Motor & Controller?

Posts: 1

7.5 Motor & Controller ?

« on: Today at 08:03:37 AM »


I just installed a 7.5 HP motor. I understand I won’t get the mileage I did with the 5 HP.No problem there. Whats going on is I think my controller is running hot and kicking it into Slow Mode.I get the Turtle showing on the screen and the speed drops dramatically within a couple blocks.Always happens when it shows 4 green bars .Now after sitting over night I ( not plugged in to recharge) I wanted to see if it would still show 4 green bars. The screen shown full charge and took off like a bat out of hell. The controller did feel a little warm after taking it for a run. I’m wondering if the controller is overheating and kicking it into Slow Mode Anyone had this type of problem ?? This is a 2005 E4 Just turned 10,000 miles & has fairly new batteries

D-Max… think you have wired something wrong… I put a 9.6 hp motor in my car… let me say I had that done… and have had no problem with the controller… if I stand on it or drive in the 35-40mph range the mileage goes down… if I stay between the 25-27mph I seem to go as far as I could with the 5hp motor… when I got the motor of course I had to see if it would live up to expections it did but my batteries have suffered for it… I have a Battsix battery monitor in the car and can see that most of the time I’m taking a pretty good draw on the batteries as there is not a lot of flat ground in Denver… on the down hill and stops they do recover back to the high 12volt mark…

for your problem… check with GEMmechanic Dennis here on the forum


Thanks BoB,
I took it for a drive today and used the slow mode instead of go like hell mode and there is a big differance in battery usage I can go about the same as with the old motor. My speed in low now is close to what it ran in high with the old motor as long as I don’t do toooo much lead footin.Thanks for your reply that’s what these forums are all about helping each other…

I believe the controller needs to be reprogrammed for the higher HP motor. You may want to check with the supplier that sold the motor. Marlon and others will do controller programming. I have never had controller issues with four stock GEMs in over ten years. GE makes controllers for golf carts, locomotives, and everything in between.


I bought the motor from Ride 4 Fun which the motor reprogramming is figured in with the price of the motor. After I had sent them the controller to be redone I called and I was told that the controller for the 2005 couldn’t be reprogrammed for this motor so I’m just going by what I was told by them…???

a famous Rabbit once said ‘if you can’t say anything nice…’ I have the program for the controller and an '05 eS… I tried making changes and took the controller settings back to stock… I’m happy without any changes… my car runs great… if R4F says the controller for the 2005 couldn’t be reprogrammed… maybe… I’d make sure all the wires are in the right places and tight… then drive the car like I stole it…