After full throttle cutoff, does your scooter self reset afterwards of you have to recycle on/off switch? Sounds like the BMS is hitting LVC, shut down the battery to protect it. Have you wired up the V meter across your battery so you can see what the voltage sag is when it cuts off?
No, it goes to 58-59km/h and then its like it releases the throttle on its own and goes max to 55, after a while it will go again at 58-59 and resets to 55. This is till i get around 80v (from 84v - which i see on the speedo). No need to stop, turn off and then turn on again the scooter. I think it should be the overvoltage protection from my controller. If it was the relay, then the scooter would kill itself for protection, i would have to stop, turn on the relay and then keep going (but this has to do with how many amps it draws, right?) plus if it was drawing too much power from the battery it would burn the fuse of the battery (i opened inside and i can see there is an 80A fuse).
I just bought
this and
this, so i can monitor my battery and have a switch to open it only when i want to measure something.
I have tested my 60V scooter on the center stand with various voltages. At 82V (24S LFP cells fully charged), scooter powers up but motor will not spin with throttle input- I suppose that's the controller protection mode at work? I settled on 22S LFP cells (around 73 to 74V fully charged, to have some safety margin)
I strongly believe that 82v are over the upper limit of your controller, so that is why it does not run. Smart move to go max 73-74v, somewhere there is the limit of your controller and that is why it runs.
I have wired in a new throttle but have not put many miles on it yet (been raining here). The problem is intermittent, difficult to diagnose. Suspected components are: throttle, connectors, wiring between throttle and controller. Last but not least, the controller itself.
Problems that could be causing this:
*Throttle itself — cracked Hall sensor, water ingress, or unstable 5V/GND line.
→ Let’s see how the new throttle performs and go from there.
**Throttle wiring or connectors — corroded pins, loose crimps, or bad solder joints.
***Controller input circuit — filtering capacitors or a faulty ADC (Analog-to-Digital Converter).
→ Remember when I mentioned in my thread that I replaced the capacitors in my controller? I noticed a big difference in torque afterward. If your controller has degraded caps or a damaged input stage, it could be interfering with signal reading. Hopefully, past overvoltage didn’t fry anything.
You could open the controller and inspect for signs of stress, corrosion, or burned components.
****Overvoltage protection — the controller may be cutting off throttle input when it sees a voltage spike from full charge or regen braking.
*****Environmental stress — does the issue happen more after heat buildup, vibration, or under high-load conditions?
Suggestions:
*Use a multimeter to test the throttle:
Red = 5V
Black = GND
Green = Signal (should smoothly ramp from ~0.8V to 4.2V as you twist)
**If the range is correct → throttle is likely good
***If the signal jumps, cuts out, or drops → possible internal short or bad cap in the controller
****Wiggle the wiring harness while monitoring voltage — check for dead spots or interruptions
*****Watch out for water — especially in cheaper throttles or open connectors
Personally, I won't even rinse my scooter until I’ve heat-shrunk and sealed every exposed connection. Too risky. These things aren’t waterproof out of the box.
