2016 GEM E2 Power Issues

Having issues with newly purchased 16 GEM E2

AGM Batteries appear original. GEM has under 200 miles on it.
Gets up to 10-15mph if you go over that it studders and sometimes shuts off. Release gas the solenoid clicks back on and goes again but never over 15mph. I believe it needs new batteries? Should they be tested while all connected or individually?

Batteries are LEOCH 6-EV-120. What would a recommendation be for replacement batteries also

thank you

Any fault codes?..

In “turf” setting by chance?

No turf mode on new Gems.
It sounds like an encoder issue or throttle. Either of those or low voltage should set a code.
See if you can get it to quit long enough to see blinking light on controller. It’s under hood and hard to see. It may be a fault that is no sent to the display.

Where are you located?

did you but it now ? can you ask them if installed speed key kit ?

RI. No there is no limiting kit on it. I checked the original batteries. Two test out over 12 volts and two are under 12 volts with CA around 110. Assuming two batteries are junk? Would that cause this to happen.

The controller limits performance with low voltage.
I suppose that it could reset without a fault.
As you need batteries in any case, replace them to see if problem goes away.

Would a dead battery limit the speed? It basically shuts down when gas petal is pushed all the way down. Once released i can hear the solenoid click again and i can move. Still not above around 15MPH.

Yes, measure battery volts under load. I most likely goes under 40 volts.
If inconclusive I can look at the sevcon lower voltage limit. However it may be done in the Polaris vmc. In that case only a dealer can tell you.