BionX Motor Issue

Hey everyone! I'm new to this forum and I was hoping I could get some help.

I have a BionX D500 DV motor system installed on my road bike.
http://ridebionx.com/products/ebike/ebike-systems/d-500-dv/#features

I rode it outside yesterday: first in an empty parking lot, then around town. It seemed to be functioning perfectly: throttle, pedal assist, and regenerative braking all worked.

Today I was using it on my turbo trainer to test its throttle and braking response in a controlled setting. During part of my test, I set the braking mode to 4 (the highest setting) and sprinted as hard as I could. The resistance was very high at first, then started to ease around 20 kph towards a minimum around 40 kph. After this, the resistance increased again up to about 55 kph. It eased again until at about 70 kph, the motor suddenly turned to drive mode and accelerated to 87 kph. At this time, I stopped pedaling and the motor quickly slowed the wheel down. After this, the head unit began beeping in rapid pairs repeated every 1 second. The assist mode bar on the control unit blinks in sync.
I start pedaling again while the system is beeping and the resistance is initially very high: twice what it was originally. Concerned, I dismount to examine the system.
Now I troubleshoot. I turn it off and on again, hoping the issue would go away.
The beeping resumes. I try pedaling again. I change the throttle setting through its full range and it has no effect. I push the throttle button and it has no effect. Despite pedaling again significant resistance for a substantial period, the battery charge is no longer increasing as it was. When I get to about 20 kph it decreases until the resistance is almost gone at 40 kph and does not increase again despite pedaling up to 96 kph. I shut off the system and disconnect the motor signal and battery connectors and find that the resistance is unchanged. The motor must be passively dissipating my work internally. When pedaling with the system on, the system seems to recognize that it's in generate mode and displays red, indicating that I'm charging it. At high speed it indicates a lower charge rate or even flashes slightly to green (drive) Through all this, the control unit and display seem to function without issue. I also restart the system a few more times allowing off time to no avail.

This is quite disturbing to me as I've only been using this bike for one day and now it seems inoperable.
I would greatly appreciate any expertise in trying to reset the motor to normal operating mode.

Thanks in advance,
~Bill

does the motor/wheel seem to have higher resistance to pedalling even with the system powered off? if so, it's possible there are blown fets in teh controller (which is probably inside the motor)..

Yes, the resistance doesn't change whether the system is on or off.

I'm not familiar with the internal design of these motors. What role do FET''s play in the system's operation and how could my stated operation have caused damage to them?

Thanks AmberWolf!

Update:

I rode my bike with the motor off to my nearest bike shop for servicing. The motor exhibited the braking behavior initially but once I got up to speed, I found that it was now coasting freely. When I got to the shop, I turned on the system. The beeping pattern persists and is unchanged. However, there is now no noticeable resistance from the wheel. The throttle and pedal assist modes continue to be non functional.

The bike mechanic didn't know how to interpret the situation. I've taken the motor system off my bike now to rest while we troubleshoot.

If the wheel does not have resistance when the system is off, but does when it is on, then the problem is probably not the FETs. IT is probably something the controller is being commanded to do.

If the wheel had resistnace regardless of being on or off, then FETs would probably be shorted in teh controller (which is inside the wheel in the ones I've seen), and causing drag / "cogging" since the phases are shorted by them.


FETs are the electronic devices in the controller that switch power thru the wires of the motor to make it move or brake. There's a few threads about how motor controllers work, and troubleshooting info on http://ebikes.ca 's Learn page, though the BionX controller doesn't look like regular ones and is proprietary, a closed system only the manufacturer / dealer can take care of for you. (you might be able to replace individual components, but if you don't know electronics troubleshooting already, it'll probably be pretty hard, as the manufacturer isn't going to help, and there's not all that much info out in the wild on the details of design/etc)

If the system is under warranty you will need to contact a BionX dealer or manufacturer to get it fixed. If the bike shop you took it to is not a dealer, it's highly unlikely they'll be able to do much with it unless they're skilled at out-of-warranty (unsupported) BionX repair.

If it's not under warranty, you'll still probably have to get hold of dealer/manufacturer to find out what the error code(s) mean, and get spare parts (whole units, not pieces inside them) to replace stuff with. They may or may not help you figure out which part without charging you.


(All of that, plus the cost itself, is the main reason I did not go with BionX when I first started electrifimotorifcating my bikes--if it hadn't been such a tightly closed system I'd've saved up for a few years and gotten a BionX system, because at the time over a decade ago, it was the only complete system that did what it does, with a good torque-based power assist).

Unless you go to a shop that has the official Bionx diagnostic dongle, it's really hard to get a system going. It might have done something that can be fixed remotely, but if you want to go experimenting with using it on a trainer and seeing how far you can push things, the Bionx system is a terrible choice for that... Highly proprietary, hard to diagnose, ridiculously hard to replace controller and almost impossible to use aftermarket parts to keep it running...

Voltron said:

but if you want to go experimenting with using it on a trainer and seeing how far you can push things, the Bionx system is a terrible choice for that...

Click to expand...

I was kinda thinking the same thing, the torture test worked, I hope it does not cost too much to fix then don't do that again,

Are you trying max regen on a full battery too, that might make her beep a bit,

Maximum allowed speed on a BionX 28" wheel ist 60kph. Maybe there is some headroom, but beyond 60kph you are out of warrenty.

After 60kph the voltage gets to high for the built in Controller / MosFet from induction.

I don't get ist why you spinned the wheel at 96kph without even asking _before_ doing so.

Do you drive your car at 100kph and force the 1st gear into it?