View Full Version : Electric Motorsport scooter failure ifnfo request

19 April 2012, 1456
If anybody else here has fixed a "non-starting" Z-6 or Z-6000 Electric Motor Sport scooter, please advise what the cause/cure was.

In the one that we're working on, the bike was working normally, got charged, then now, won't go. The lights work, though.

Battery pack voltage is good.

This scooter has requires that a rocker switch be rocked on, then off, and the kickstand be in the up position.

There is less than 900 miles on this bike.

Our test equipment includes a low voltage non-contact DC/AC sensor, a DC clamp ammeter with 0.1 resolution, and a DMM.

All suggesions (and even good humor heckling) appreciated, with thanks.

We have not checked fuses or anything yet.

19 April 2012, 1502
I owned two EMS GPR-S motorcycles. The first one stopped charging when the BMS burned up. The second one had its BMS fail also, which took out the battery cells over time (before I realized what was going on). After installing a new BMS, it then would stall without warning due to a "contactor failure", according to the controller programmer. I was never able to solve that problem completely and have moved on to a Zero. All I can say is good luck and I hope you can resolve the problem.

20 April 2012, 1351
We got it fixed rather easily.

The brass nut on the motor wiring lug was loose, right from the factory, due to partially stripped threads.

A temporary fix was made with steel washers to bring the nut higher on the motor bolt, and glue to keep it together.

Sprayed the nut and bolt with DeOxit (not as good as MG Chemicals Super Contact Cleaner imo) because the steel-brass contact will eventally corrode.

Also sprayed the other motor bolt-nut.

After this fix, the scooter ran fine.

In addition, the low-speed throttle oscillation disappeared, and the throttle was silky-smooth.

Replacement brass nut will have to be found. It is not SAE size.

Glue is holding the temporary fix in place.

24 April 2012, 0823
Hello Nonpolluter,

Find some blue loctite, it is great to keep things from loosening up.

Los Angeles