Controller Programming (speedometer)

Is there any programming that can be done to the controller to correct the speedometer for tire size or transaxle ratio changes? I see you can get a CD to allow a laptop computer with a serial or USB cable to reprogam the GE controller.

Marlon in the San Diego area can help you with this if you are close… if not close he might lend you the equipment…
619-247-4044 evenings until 1am west coats time


I’ve had a good experience with Marlon. I rented a GE controller handset from him and calibrated my speedometer to 12" tires and got the Gem to do 35 on flat land.

Now that I have the extra juice for my 5 hp motor I made a heat sink for the motor out of inexpensive parts. Hopefully this will aleaviate the need for a 7.5 hp up grade.
See my video at: GEM Car “GE Motor Heat Sink” - YouTube

Lookin’ good Chuck! Let us know the before & after temps you are seeing.

[QUOTE=LuvMyTJ;12541]Lookin’ good Chuck! Let us know the before & after temps you are seeing.[/QUOTE]
Before 175 F. After installing the heat sink 130 F at 35 mph run on level ground. I thought about putting some aluminum antiseize grease under each fin for better heat conduction. But I don’t need it. Now if I lived in a hotter climate I would. I did add the copper spacers so that the heat sink covers 3/4 of the motor. Plus it spaces the “U” channels out so that air can get to each fin. The heat sink is over the field and armature coils where most of the heat is generated.

and the next question… will you go into production and sell a few on these?


This is good news. I have wanted to go faster but was worried about the additional heat generated by the higher rpm’s. Your “heat sink” is a fantastic idea!

Chuck what settings you changed to get your current increse in speed ?

You will have to rent a GE Handset from Marlon and set F3, F7 and F20 so that more current gets to the motor and the speed limit is set to above 35 mph. In my case I had to check or change 50 settings on the controller. I have enough experience to be dangerous. Marlon is the man…

I have the GE Sentry for windows. Just doing some instructions before I dive into the microprocessor and attempt any changes. I may have to contact him also.


When I bring my Gem home from it’s summer duties I will have to contact you about renting your setup. :phone:

I thought some of you might be interested in my latest results after using Marlon’s GE Handset to re-calibrate the motor controller. Using his last setting recommendations I have two options now that are really neat. Turf mode has a gentle take off and a top speed of 28 mph. This allows me the original battery conservation and mileage. Street mode gives me a wheel squealing take off (surprised the heck out of me) and a top speed of near 40 mph on level ground and uses the battery at a somewhat faster rate. I put a heat sink on my 5 hp motor to help lower the motor temperature as I think you could fry it on long steep hills and sustained wide open driving.


Thanks for the tip man.

In addition to your heat sink that I will make later on. I mounted a temp gage and two sensors. I will spread the two sensors on different spots on the moter. But for now I have them close together. Maybe one on the gear box and one on the moter. Not sure yet still in the works.


Good…the gear box doesn’t get so hot. With the newer cars the motor is more exposed so you could mount more and longer fins and use the conductive grease. My e2 is lighter and hauls less weight. So the motor is taxed less than a e4 or e6…

I have a T4 that I mounted on a large heat sink with the other sensor under the controller. What’s the operating temp of a controller suppose to be ?


what model is the Taylor hear gauge?


Taylor 1442

Marlon, HELP, if you were going to buy new batteries what would you buy. If I am only changing batteries do I need to make any changes to my controller. I have Trogans now, looking CG-12s or Opitums what do you think, Thanks, Kenny 2001, e825

I just accuired a GEM e580 and top end is 15 mph./ what do i need to do to raise it a little