I have 14 in wheels. Can changing my rolling radius to 10 inches give me more speed than 25MPH ? My 2012 E-4 has a five HP moter.
By going to a smaller wheel diameter you will go slower. When it comes to wheel size smaller means quicker take off with slower top speeds and taller wheels will have a slower take off with faster top speeds.
If you are looking for more speed there are controller settings that can be made. Beware though, it is not as simple as just having the controller tuned… you will need to consider the additional heat generated by the motor, additional stress on the electronics, and you will likely shorten your range.
I have to admit, if your type of driving allows you to go faster, than more speed is certainly desirable.
Thank you very…
al
Thanks ,Marlon
I’m trying to get 30mph by tricking the controller and stay within the 5hp moter range. If this is not possible with the stock 5hp i will upgrade to the 7.5hp witch has a better opperating temp %.
I was hoping for 30mph without the hardship on the little 5hp moter.
I’ll call you when I get back to my location sometime in the near .
al
[QUOTE=Blackhorse;12615]Thanks ,Marlon
I’m trying to get 30mph by tricking the controller and stay within the 5hp moter range. If this is not possible with the stock 5hp i will upgrade to the 7.5hp witch has a better opperating temp %.
I was hoping for 30mph without the hardship on the little 5hp moter.
I’ll call you when I get back to my location sometime in the near .
al[/QUOTE]
Be sure and check out fellow member [B]chuckkent[/B]'s video of the heat sink he designed for the Gem motor… it’s brilliant!
Anyone know of a temperature gage that can mount like that with a onboard display going inside the vehicle ?
al
Not sure what you mean by rolling radius? A change to the circumference of the tires will change the top speed of the GEM. If the tire circumference is increased, the speedometer will read low and the motor amps will be increased. The regenerative effect will also be reduced. A major increase in tire circumference may cause controller and motor overheating issues.
Daniel
On the same subject, I’m wondering what the “conversion factor” is so I know what speed I’m going with 14" wheels on a 2005 e2 I just purchased. It has the larger wheels/tires and the 7.5 hp motor, but the highest speedo reading I’ve seen is 15.
And can the speedo be reset to read the actual correct speed with the 14" wheels? Thanks.
[quote=tomarys;16743]On the same subject, I’m wondering what the “conversion factor” is so I know what speed I’m going with 14" wheels on a 2005 e2 I just purchased. It has the larger wheels/tires and the 7.5 hp motor, but the highest speedo reading I’ve seen is 15.
And can the speedo be reset to read the actual correct speed with the 14" wheels? Thanks.[/quote]
its kinda kard to tell what the correct speed would be…but all you have to do is get a GPS on your phone or other device and check it that way…i use my GPS on my phone all the time…i have put different gears in my gem and my spedo is just about cut in half…if its reading 20 im doing about 39ish mph…that will be the easy way to get a idea of whats going on.
Thanks…I don’t have a smart phone (I’m not smart enough for them, probably), but I’ll find my old gps and do it that way. Thanks!
no problem 
The '02 has the T2 controller which, with the programming software & cable or the handheld programmer, can be adjusted for more correct speedo readings. Normally, R4F does this when you get their motor and send them your controller and the desired wheels/gears combination info.
The software solution costs about 75 or 100 bucks (can’t remember exactly) and requires you to have a Windows XP PC with a serial port (rare these days) but there are probably tons of older ones available on the used market. It allows you to adjust the motor settings for more speed and to adjust the speedo reading and acceleration factor etc. It’s not for the technology-challenged though.