Looking for some help here

deacon · #1 (**permalink**) 06-30-2009, 05:39 PM

I haven't tried to ride my hub motor in a month or more. So today I tried it out. I have major problems. First of all I checked the battery and it was full. Then I hooked it up and the light came on the controller and on the throttle. I started off and the throttle showed the battery weak. I was more than a little surprised but it was down **** for the first half mile. I hit the throttle and it responded so I was satisfied. then when I hit the throttle next nothing. The throttle led showed the battery dead so I pushed the bike home I figured the batteries had run down for some reason. When I got home I checked and the batteries were fine.

the low voltage light was burning so I checked the batteries at the controller. Over twenty five volts that should be well over the required amount. The bike will not start.

If you have any ideas I could use them. I am actually thinking it is the hall sensor. That seems to be the weakest link from what I am reading. The low voltage led on the throttle has me stumped. It might be something in the hall sensor circuit though. I got it a lot even when the bike was running so I'm not sure that sensor might have been bad from day one.

If you know anything about this stuff let me know.

Stubby79 · #2 (**permalink**) 07-18-2009, 02:57 PM

Reading 25 volts at the batteries does not automatically mean they're good or properly/fully charged. Lead-acid batteries can short out inside, sulfate or otherwise wear out/break down. The way to prove if they're good or not is to check the voltage at the battery while under load. That is to say, use your multi-meter/volt-meter to see what voltage your batteries drop down to when you crank the throttle. Fully charged, really healthy won't drop more than a couple of volts. If they drop below 10 volts per battery (20 volts in your case), they're either in need of a charge or are shot.

If the voltage doesn't drop much, if any, and your battery meter on your throttle is reading low/dead batteries, you've got an electrical problem, most likely a loose or otherwise poor connection, probably between the batteries and the controller. I see this as more likely than bad batteries, seeing as it worked at one point but not the next. A poor connection between the controller and the motor would not cause this. A poor connection, like a bad battery, would let a small current to pass(amps), but as soon as you exceed that limited current, the voltage(from the poor connection on) would drop down to practically nothing. No volts to light up your battery meter, neither volts nor amps to turn the motor. This bad connection could even be inside the controller. Or, if you have a master on/off switch between the batteries and the controller, the bad connection could be inside it.

Third option is a short inside the motor. Not likely, unless it's a brushed motor, but even then it probably wouldn't have worked earlier in the ride (unless spinning the motor is enough to interrupt the short momentarily, likely a brush shorting out somehow).

Let me know if you need more ways to test things.

deacon · #3 (**permalink**) 07-18-2009, 03:24 PM

I took the controller apart and read it. One of the wires to the motor that should have had power when the throttle was on full had none. I checked several other things as well. I have no idea but I might have damaged the controller a few rides ago when I tried to over power it.

I also reused the throttle on a different motor and it works fine. I reused the sla batteries on a different motor and they worked as well. I'm pretty sure the controller was bad. I have a 36v 350 watt one on the way. It should allow me to over power the motor and run it. At least that is the plan. Thanks for the information I will keep it in mind for later should I have battery problems.

I checked the voltage at the entry to the controller and it read over 25v as well.

Stubby79 · #4 (**permalink**) 07-18-2009, 03:51 PM

Have a quick check of the circuity of the old/burnt out controller. Most likely you burnt out one of the power transistors, but you might have been lucky and simply put more powered through the printed circuit board than it could handle, and it might have burnt out at a weak spot, which could just be re-soldered together if it did.

deacon · #5 (**permalink**) 07-18-2009, 04:08 PM

It ended in the trash but I suspect that it broke down the transistor, since it just stopped on the 36v supply but woke up when I went back to 24 voltes. I ran it about two miles on a later ride then it just wouldn't do anything when I tried again. The low battery stayed on. This one coming should take care of it the problem. If not I'll do something else