New project

GEM Forum
1

Got my new 2010 truck in.
I’m sure this is old news for some, but controller is set at max speed, and only goes 26mph and holds back.

I know about some of the “fixes”.

Would you be interested in a magic box that plugs in with no wiring changes?
Can be removed without ill effects.
No programming changes to controller.

Car and speedometer would work the same as stock to 24-25 mph then continue gaining speed to the limit of motor capabilities.

Magic box could also have a tach and speedometer outputs for standard gauges.

I see no reason that this wouldn’t work on older cars also.

Have an idea how I would build it.
Parts are inexpensive.
Considerable development costs.
Probably not worth while unless there was good demand.
Target price= <$50. Hand built ones ~ $100

Development time = As health permits.:rain:

2

Thought there would be interest in this.:confused:

More basic description:

Electronically remove magnets

Reversible

Programmable

Switchable

Increase speed over controller setting (255)

3

Hi
speed setting 255 are this 25,5 mph ?

4

255 on GE controllers is a maximum setting used for more than one parameter.

In this case it fits.

5

I would take one for sure My T3 has the 4 pole magnet and my speed and trip ( miles are way off)

6

Not sure I understand.

You reprogrammed for more speed and MPH are off?

Haven’t done anything to my T4 yet.
Except put a tach on it. >5000rpm @ 26mph

Not even sure my idea works. Researching.

7

The T-3 needs a Software fix to overcome the 25mph speed brake. The way you overcome the 25mph speed limit programmed into the T3 is you change the Motor speed sensor magnet from a 8 pole to a 4 pole magnet this tricks the Controller into thinking the GEM is only going 1/2 as fast as it truly is. Example when your dash reads 20 MPH your actually going 40

8

Got it.
I was aware of the method. Not the specifics of some using an 8 pole magnet.

My Tomberlin T3 uses 4 pole magnet and my new Gem T4 truck uses 4 pole?

If this is correct it will make a difference in some of my projects.

If you decide to try tach, as configured, it will read double with 8 pole magnet. Or 1/2 with 2 pole. Easily corrected, by reprogramming.

9

If my project worked as planned, mph would be correct until reaching 25 mph. Speed could increase but it would still read 25.

This may not be that helpful or even worth doing except for not needing magnet change.

Reading 1/2 speed as yours does, doesn’t seem to be a big deal.

Believe I’ll put on hold for a while.

I do have a tach for you to play with if you want. Also field programmable as speedometer.

10

I could be wrong on the exact numbers of poles on the Magnet. What ever the number its 1/2 of what stock is. R4F claims they have a software fix. They claim that they can re-flash your T-3 so the MPH is correct and they can remove the 25mph limit.
The danger in using a magnet that is 1/2 the poles and tricks the controller it will allow the motor to OVER speed. Like what Rodney has been saying all along that these motors will not live if you over spin them. With the 1/2 pole magnet I could potentially get my gem going 50+ mph down hill. Because at 50mph my dash would only still read 30 Mph. R4F has warned me about down hill overspeed potential OR motor "break up " or failure. That over speeding the car could result in a motor coming apart. So I keep it at 40 or below.

Right now my 08 has the 12:44 gears. And that puts me right at or slightly about the RPM red zone at 40 MPH. I have the car located at my home that’s 99%flats. I am on the fence weather to install a 10:35 or a 8:9. I have both gear combinations on my bench right now and a extra transmission. I just can’t decide which one I should go with. I feel like if I go with the 10:35 I will be safe for increased pay load (passengers) and mild hills. With a slight increase in speed (41-44) mph. With the 8:9 gears I will could see speeds close to 45-48 mph that would make or help me keep up with Traffic on the El Camino and keep tail gaters off my bumper, but hills with passengers inside will be a NO NO. I’m just not sure what to do its a real trade off.

11

I see a market for device then.
Can’t compete with control modification though.

It could be programmed to limit over speed.

0-25 = no change

25-40 = read 25 mph
>40 = read 26 mph controller works to keep speed under 40 by telling control it’s 26mph.

Low cost
Easy plug-and-play
Reversible when time to sell

Just an idea so far. Not sure I’m up for it!

12

I have been told by two sources, one is R4F and the other is a gem parts man at a Chrysler dealer here in FL. That the magnets in my 7 hp factory motor in my 2008 car are different than the 5 hp motor and can not be modified or removed.

R4F and the dealer man claims the only way to get over the 25 mph hump is to modify the controller or install a R4F four (4) magnet motor . The pod will then read half the speed unless the controller is modified. RF4F claims that this modification is in addition to the free mod when you buy the 7.5 motor. I believe its $275 extra?

I only know enough to almost be dangerous…

13

If that’s true, then a simple “sensor pulse” scaler might find a market.

Rather than halving pulses output could be set to **% of input.

Offering a **% increase in speed.

Removable
Programmable
Switchable-in/out

Once the hardware was designed, programming could do a lot of different things.

14

Hi Inwo
how can R4F program controller to read higher than setting 255 ?
they take 295$ and display will read over 25mph
can this be true

15

Someone should look at the oem settings.

There are many ways to do it if they have access to the right information.

The 255 would seem to be a hard limit. Other things could be reconfigured to let 255 = over 25mph.

If it’s only Gem models that are limited, maybe they reflash it to generic settings.

I can only guess, not having seen one.

In any case it should be a $40 fix.:rolleyes:

My only solution is scaling pulses from tach sensor, not a whole lot better than magnet change.

16

R4F says they payed a softwear company a bunch of money to make a patch or softwear patch to overcome the speed limit.

17

That makes sense.

I’m just a hardware guy.

18

Doesn’t the “D & D” motor company build all the motors that R4F sells and modify the controllers also? Is R4F just a cost adding company between us and D & D?

19

D&D makes the 7.5 for Ride for Fun. Up until recently R4F had the exclusive right to sell the 7.5
When that agreement ended that’s when we all saw the Black Motor R4F was pushing they called it the Raptor. Made by Advanced Motors.

Ride for Fun actually went to court with D&D because they thought they had the exclusive to sell the 7.5

That Raptor motor that R4F was selling for what ever reason did not work out to well. And R4F went back to the D&D motor.

20

[QUOTE=Gwest;28224]D&D makes the 7.5 for Ride for Fun. Up until recently R4F had the exclusive right to sell the 7.5
When that agreement ended that’s when we all saw the Black Motor R4F was pushing they called it the Raptor. Made by Advanced Motors.

Ride for Fun actually went to court with D&D because they thought they had the exclusive to sell the 7.5

That Raptor motor that R4F was selling for what ever reason did not work out to well. And R4F went back to the D&D motor.[/QUOTE

[B]Thank you… You da man![/B]

I have a friend that bought a D & D motor for his 29 Ford golf cart last year… it was cheaper than R4F. D & D also reprogramed the controller at no cost. He has just now bought a old Gem (2002 ) and has talked with D & D about a new high rpm motor. He says that D & D is willing to sell it too him, about $200 under R4F…