I have been reading from here for a while while doing research for a golf cart for cruising around my neighborhood and maybe registering it in the future to drive around town here in Florida. Spent around 4 months trying to get a ezgo or similar but wasn’t as fast in snatching one as the cart rebuilders are here locally.
I came across and got IMO better then a golf cart, a 2002 Gem e825 4 seater. I tore it down to the frame to repaint it, clean out rust, and such. I am currently working on doing the following:
Replace front seats, seat mount/frames rusted out
Back bench seat replacement rotted wood and aged vinyl
New larger rims/tires
For acceleration and speed I Initially planned to replace the motor with the R4F upgraded motor as mine sounds like it has a catch on one of the contractors as it thumps when starting. Then down the line do a Lithium conversion as my and my wife’s cars are both electric and love them.
However I have read on here that better batteries, more powerful and a stock controller reprogram can give me the speeds I need without a motor upgrade. While I don’t know if a place to get it reprogrammed I thought I saw one for sale here that I could get and do it myself.
Questions I have is there a benefit to reprogramming it now with standard deep cycle lead acid batteries? Meaning can I simply lift the top speed lock as is without harm or is reprogramming only useful in the event of motor or power upgrades?
Thanks for all your previous posts and input! Very helpful so far.
You have a 5HP motor and can set the top speed higher by reprogramming. On a 2 seat cart you can get maybe 29 miles per hour with out too much trouble. On a 4 seat cart maybe 27. Best to get a RFF 7.5 motor and reprogram the controller. Your cart has a 10.35 gearbox. The optimal Tire diameter for that gear box is 21 inches. The popular idea of large diameter wheel/tire combo may look nice but can affect acceleration and breaking adversely. Your cart has the drum brakes and IMHO are unsafe above 30 MPH with out modification. Larger tires make the problem worse. Your blessed with a T2 controller. hands down the best controller ever installed on a GEM cart. I recommend a 205-65-10 tire/wheel combo with the 10.35 gear box. It works well and looks good. Email me and I will return a picture of my machine. Ebay has 14 inch combos with lo profile 21 inch dia tires that are reasonable.
I was targeting a 24” wheel diameter as the cost of the 10-14” golf cart wheels bother me. Picked up some 16” wheels super cheap, still working to pick out tires, trying to stay away from flat low profile tires as I know wider and flatter reduces range, did on my car at least.
Sounds like motor upgrade with controller reprogramming would be my best bet first over better batteries with more power. 30mphnis really all I looking for now, maybe in a couple years that will change.
24 inch wheel diameter is a killer. 5hp with a 10.35 gear won’t cut it. Where did you come up with your information on wide flat tires? Very interesting, I have been building Gem cars for 6 years. Never heard that before. Hope your on flat ground. Dont get rid of your stock tires and wheels. Good Luck
The 24” total wheel diameter I read on here as being the sweet spot, I’ll find it back and check as thinking about I now I don’t recall if it was referring to this model.
The reduced range due to wider low profile tires I use is from my experience with My Tesla Model S. I changed from 19” to 21” wheels with low profile tires. Now I have more Surface area contact and that requires more torque to move. Lost about 10 miles of range on my car. Will switch back to the 19’s once I need new tires.
24 inch are the sweet spot, in some peoples eyes. Unless you make performance enhancements they actually degrade performance with a 10.35 ratio. They are mostly used on 12.44 carts. You also have clearance problems with out lifting the cart.
I’m new to the forum and others recommend you as the guy to talk to. I have a 2001 e825 with 21 in tires and brand new Trojan batteries. I recently replaced the stock 3.5hp motor with a used 5hp motor. I had to move the right front shock to make room for the motor. Despite having the speed limiter removed, it goes no faster than the old motor. I get about 22mph tops.
Assuming the controller is the limitation, what I need to reprogram it? I don’t want to spend the money on a RFF package just yet and would like to see what I can squeeze out of this motor.
Greetings all, your carts look great and the knowledge here seems like the place to find some insight on some issues I’m facing.
I live in Mexico Beach, Fl and was given a 2002 Gem e825 4 seater from a neighbor I helped out after the hurricane.
Basically, the cart was totally submerged in saltwater by the storm and I’m attempting a rebuild. From what I can tell, the batteries and motor are good. I replaced the T1 controller, on-board charger, fuse box, parking brake switch, and rewired everything cutting out all the corrosion.
I have not yet replaced the 72 to 12 volt converter, main contactor, potentiometer, and the other small relays that appear to be flasher relays.
I’m actually having a hard time finding a suitable wiring diagram for the key/ignition switch (which wasn’t connected when I got the cart.) Also curious if the voltage converter is required to start the cart.) These are a couple things I’m trying to figure out before I go deeper down the rabbit-hole.
Thanks in advance for any advice or input, even if I’m nuts for restoring a sub-ocean cart.
Personally I would pass. I would think your gonna need to replace Everything. BecUse if it ain’t broke now i would think it will break down the line. I would hate to chase Down all the electrical gremlins that are gonna pop up. I would think all your connections are gonna have some issues. With that said I would think you could buy a complete wire harness
New charger $350-$400
New motor $500-800
Have your controller rebuilt $500
And the list go’s on, I see $1500 right off the bat.
You’re not wrong. I already have a new controller and charger, the motor seems fine ( for now). It’s more of a personal challenge now than $ vs resale value if you know what I mean.
Thanks for your thoughts though,
I apologize if this is not the correct approach for asking you a question, but I’m stumped and frustrated with the information available online. It should be rather simple, but I inherited a 2002 e825 which I’ve been working on for quite a while. My problem is that the wires for the key/ignition switch were not attached and I’m trying to find where they originate from. Any information would be more than appreciated…
Thanks, Chris
Rusty_Gem
March 2
I apologize if this is not the correct approach for asking you a question, but I’m stumped and frustrated with the information available online. It should be rather simple, but I inherited a 2002 e825 which I’ve been working on for quite a while. My problem is that the wires for the key/ignition switch were not attached and I’m trying to find where they originate from. Any information would be more than appreciated…
Thanks, Chris
(Attachment 2001-2004 GEM service manual.pdf is missing)
(Attachment GEM 2004 prior WIRING DIAGRAM.pdf is missing)
(Attachment GEM DC DC CONVERTER UPGRADE.pdf is missing)
