Grubee kit troubleshooting

[knurn]

Knuckles I'm hoping you can help since you have some experience with Grubee kits.

I have a Grubee (Skyhawk) 48V 500 Watt front hub motor kit (direct drive). It stopped working after a couple of weeks and minimal usage. I couldn’t find any distributors so I purchased a modified controller. This controller is not a ‘direct fit’ but I think I have it connected properly.

If I give it throttle and lift the front wheel it will spin but not smoothly - there is some humming and intermittent loss of power. The motor doesn't have enough power to move the bike even without a rider.

Is it possible to wire the motor directly to the batteries? Is this a good test to determine if the motor is not damaged? If so what wires from the hub motor do I connect directly to the batteries?

Any other suggestions to systematically test and eliminate the throttle, controller and motor?

 

[fechter]

You can't connect the motor directly to the batteries if it's a brushless motor (more than 2 wires coming out).

It sounds like the wiring is not a straght match. You probably need to try some different combinations.
For some hints see this: http://endless-sphere.com/forums/viewtopic.php?f=16&t=3484

 

[Knuckles]

Have No Fear!

Knuckles is Here!



email me at rnich01@optonline.net

I take care of all your sh*t! 8)

easy peasy

 

[John in CR]

I have that motor on my bike and those symptoms are exactly what a wrong wiring config can produce. ie No load (tire off ground) spins pretty good, but grinding/vibrating sound as it is accelerating, and not much of anything under load.

John

 

[knurn]

Hi John, as I mentioned I am using a different controller since mine seems to be fried. I sent the complete list of hall and phase wiring configurations and results to Knuckles. The problem is none of the combinations solved this problem so there may be some other connectivity or incompatibility problem.
How long have you had your 48V 500W Skyhawk?
Are you still using all original components?
Do you have any speed and range findings for your setup?

 

[karma]

your old controller could have fried one of the hall sensors, im more than happy to set it up for ya. if i dont get ill give you a full refund

ill even pay to ship it back.


cheers

 

[Knuckles]

knurn,

I think you had bad SLA batteries and possibly a bad throttle connection.

Assuming I am talking about the same person with the 48V Grubee.

Any news?

 

[knurn]

Hi Knuckles,
Yes this is the topic that you initially responded to and asked me to contact you by email.
I soldered some poor throttle contacts. Yesterday I returned the two batteries with the low voltage to the vendor. He somehow forced a charge into them overnight. I brought them home and was able to ride the bike for about ten minutes and then the same problem returned. The motor couldn’t work under load and kicked in and out. The batteries would charge for a couple of minutes and then appear to be fully charged but the motor wouldn't work under load. The motor appeared to work properly when the chargers were plugged into the battery rack sockets and the throttle was enagaged. I’m using the original Grubee controller with the low voltage cut-off.
Tomorrow I will pull the batteries out of their racks and check their voltage. Next week I will go back to the battery vendor. If I don’t get a refund or new batteries then I’ll have to mothball the ebike until next year and then I will give it one more try with a different battery chemistry.
Knuckles thanks so much for helping me with the troubleshooting.

Karma the controller I purchased from you appears to be working properly. I’ll let you know if either controllers need to be modified to work with the new power source. Thanks for following up and offering to help.

 

[fechter]

... The motor appeared to work properly when the chargers were plugged into the battery rack sockets and the throttle was enagaged. I’m using the original Grubee controller with the low voltage cut-off.
Tomorrow I will pull the batteries out of their racks and check their voltage. Next week I will go back to the battery vendor. If I don’t get a refund or new batteries then I’ll have to mothball the ebike until next year and then I will give it one more try with a different battery chemistry.
Knuckles thanks so much for helping me with the troubleshooting.

That sounds like the battery voltage is sagging under load enough to trip the low voltage cutout.
See if you can hang a voltmeter on them while this is happening.

 

[karma]

Hi Knuckles,
Yes this is the topic that you initially responded to and asked me to contact you by email.
I soldered some poor throttle contacts. Yesterday I returned the two batteries with the low voltage to the vendor. He somehow forced a charge into them overnight. I brought them home and was able to ride the bike for about ten minutes and then the same problem returned. The motor couldn’t work under load and kicked in and out. The batteries would charge for a couple of minutes and then appear to be fully charged but the motor wouldn't work under load. The motor appeared to work properly when the chargers were plugged into the battery rack sockets and the throttle was enagaged. I’m using the original Grubee controller with the low voltage cut-off.
Tomorrow I will pull the batteries out of their racks and check their voltage. Next week I will go back to the battery vendor. If I don’t get a refund or new batteries then I’ll have to mothball the ebike until next year and then I will give it one more try with a different battery chemistry.
Knuckles thanks so much for helping me with the troubleshooting.

Karma the controller I purchased from you appears to be working properly. I’ll let you know if either controllers need to be modified to work with the new power source. Thanks for following up and offering to help.

no problem enjoy