Front Disk Brake Conversion - Early GEM E825

Hello Everyone,

I’m new to the boards and relatively new to GEM cars. I just purchased a nice used1999 E825 garage queen. It’s in really good shape for an older care.

Went to upgrading some things right away. Replaced the Schott charger with a new Ride-4-Fun Supercharger and replaced the stock 3.5 hp motor with the Ride-4-Fun Raptor motor. Sent the controller of for reprogramming. Replaced the stock 12 inch wheels and tires with a set of 14" aluminum wheels and 185/60/R14 Kuhmo Sense tires. Everything is coming together, which brings me to my question and reason for this post.

Who here has upgraded the front drum brakes to disk brakes? Where did you purchase the kit? If not a kit, then how did you do it, and how much fabrication was involved? And mainly, how much did the braking ability improve?

Thanx for any feedback you guys can provide.

South Louisiana

I upgraded my 01 E825 truckette with front disk brakes last year. Got the “complete kit” from “NEV Accessories” ( Whole thing cost $580. Came with everything you needed (calipers, pads, rotors, mounting bracket, brake lines, adaptor parts and some pretty basic instructions). If you’re relatively handy with hand tools you can get it done in about 3 hrs including bleeding the brakes.

I’d seen it listed at one time on their website. When I was ready to order the kit, they didn’t have it listed on the website anymore. I called them and asked about the kit and they called me back a few days later saying they had found the brackets they needed to complete the kit and could ship it if I still wanted it. So if it’s not listed, give them a call anyway. [I]UPDATE: I just checked their website and while the kit is listed under “Brakes” it is OUT OF STOCK. I’d call them up.[/I]

Makes a [U]big [/U]difference in stopping power though it took a maybe 15 or 20 miles to break in the pads and rough them up for maximum stopping ability. My GEM had been reprogrammed for 35+MPH with a larger 7.5HP from R4F. With the OEM drum brakes I never felt very comfortable stopping from that speed. With the new disk brakes, it can lock the wheels and bring me to a stop in a hurry. Highly recommended if you’re “over speeding” your GEM.

Curious about your 99 E825. Didn’t that have a 48V system? I thought prior to 2000, they were 48V instead of 72V.



Thank you for the feedback on the brakes. The kit from NEV Accessories is one that I have seen online. I also found a kit available out of Florida for $650. The picture used on their website is the same picture as the NEV Accessories site? Anyway, I’ll call NEV Accessories on Monday to see what they say about it. Worth a phone call to save $70. I’ve already sent them an email, but I haven’t received a response.

About the car being 48 volts? I don’t really have any knowledge as to the history of GEM cars. All I can say is that the title on the car says 1999 and it is for certain a 72 volt system. I find the topic to be interesting because you are not the first person to mention this to me. When I purchased the car, I wasn’t aware of any major electrical changes in the early years. Availability of used GEM cars down here in the south is fairly slim. I missed out on a 2002 that sold for $2700 in my home town. It was a little rougher than the one I ended up with and it needed batteries. Found the 99 one on ebay and drove to Houston to pick it up. Price was a little higher ($4400), but the seller had several potential interested buyers and declined a lower offer. I guess the market dictates the price.

I’m interested to know more information on the topic of when GEM switched from 48v to 72v. Could it be that they offered both 48v and 72v and then later eleminated the 48v. Maybe to streamline inventories and production?? Is is possible the car I have was converted to 72 volts? Just throwing out ideas. It does have the updated Sure Power 71030i voltage converter. I didn’t look at the controller that closely before sending it of but it looks to be a T1 or T2 type. I’m not quite sure what the difference is in the two?

Thanx again for the information on the brakes. The concern over the cars ability to stop from higher speeds is something that Jim at R4F expressed to me when we were discussing where to cut off the top speed. He got me thinking. It’s a pricey upgrade, but one I feel is well worth it. Safety has to be a top priority. Even with everything I’ve spent on the car so far, I’m still less than half the cost of a new 4-seater with 14" rims at my local dealership, and I really enjoy tinkering with it.



Don’t really know much about 48v vs 72v GEMs except I’d read that in the “early years”, the GEMs were 48v and GEM quickly converted to 72v systems since the 48v units didn’t have sufficient power or range. Your unit may have been converted at some point to the 72v - I don’t know what year they started w/ 72v. I THINK the GEMs were introduced around 1998 so maybe they switched in 1999.

Regarding the controller, my understanding is they originally used the GE T1 controller (250Amps) but then switched to the GE T2 control(350Amps). Eventually they switched to even later controllers which are NOT nearly as programmable. For example top speed is hard wired at 25MPH and not software adjustable. I’ve been given to understand that you can circumvent that by removing 2 of the 4 magnets on the speed sensor so the controller only reads half the actual speed. Fortunately my T2 controller works well with my R4F 7.5HP motor. I also understand that the T2 controller can be rebuilt for 500Amp service if needs be though it’s not cheap to do so (I heard $500 quoted).

Good luck with your mods. GEMs are a ball to drive once you get everything sorted out. I’ve had my 01 E825 short-bed a couple of years (paid $6500 - it had been rebuilt and repainted from ground up when I got it). Invested another $1500 in motor and charger upgrades; $1200 in Trojan batteries after only one year with marine-grade batteries (BIG mistake w/ the marine batteries) and then the $580 brake upgrade. I have [B]way [/B]too much money invested in it of course but as I tell my wife if I keep it long enough, the $/yr will come down!! Unfortunately since I live in OH and can only drive it maybe 150 days/yr, my $/mile won’t ever drop below the cost of my wife’s hybrid (which she in turns points out along with my range and climate limitiations) so “practical”, it’s not. I view it as my “toy” and enjoy every minute I’m driving it (that’s what I call the $/smile factor).

I do wonder who in the world purchases new GEMs. Last time I priced them they were $12,000 to $14,000 with the same limitations we’re all dealing with. Guess there must be those with money to burn. I know one local arboretum had 3 E4’s donated to them to drive mobility-limited people around the park. Fortunately I own a business in town so I put the name on the vehicle and write off a lot of this as “advertising” or “business expense” when I drive around and pickup/dropoff people and services.


The original controllers on the 48 volt Trans2 and GEM was made by Curtis and used an external reversing mechanism. Somewhere on this forum are pictures and the schematic. Trans2 appeared in 1996, became GEM in 1998, became 72 volt during 1999.