Lost Power

[praskal]

Hello,

I have a Crystalyte RoadRunner Hub Motor (4825R) on 26" front Wheel. I use a 48V 10ah LiFePo4 pack. This has been working great for 2.5 years. While riding home from work last evening suddenly something bad happened. Power to the motor was decreased about 95%. The wheel will hardly move at all. There is a lunging/clicking sensation when I throttle the accelerator. I checked all the connections, and everything is fine. I turned off the controller for a while and pedaled. I then tried it again and it worked normally for a couple minutes, then it went right back into lunging/clicking and barely working. I have no idea what happened. Can anyone venture a guess??

Any help will be greatly appreciated.

Patrick

 

[FMB42]

I'd start by checking the following:

1. Battery voltage (your symptoms could very well indicate a low or bad battery imo).

2. The connectors and/or connections (again). Make sure that no connector pins have been pushed out of the connector housing(s).

3. All wiring (i.e. for damage, cuts, worn/torn insulation, etc).

4. The throttle.

BTW, can you tell us of anything that might have happened or occurred just before this issue appeared? This includes any crashes, repair work, modifications, exposure to rain or water, etc?

 

[praskal]

Well, Living in Portland Oregon there is a fair amount of rain exposure. I try not to ride it during particularly bad rainy days, but there has certainly been rain exposure here and there. And no, there was not anything unusual such as crashes or repairwork before it happened. Basically I was just on a long slow decline and it suddenly started acting up, clicking when applying the throttle. I did a search on the symptoms, and it looks like it most closely resembles a blown hall effects sensor. It could be in the controller or in the motor. I'm taking it to a local ebike shop this evening for diagnosis.
phr

 

[biohazardman]

What rain here in Portland? I don't see any but then again I don't have any windows to look out at the moment. ;^) If it spins smooth by hand good chance it electrical. From my experience controllers usually go before motor stuff. I have had several controllers fail but both motors have over 4K on them and are doing fine. In Gresham are you near?

 

[praskal]

I'm in NE PDX close to Grant high school. I ride all the way through downtown up Washington park and all the way to St vin cents hospital area. I never see any ebikes, and I have been riding for years.

So the bike guy here in Portland at the Ebikestore looked at everything and surmised that both the motor and the controller are okay. He noticed that a couple of the connections look like they got a bit hot and don't have the best connection.  So he's going to pretty much overhaul the whole connection system with better plugs and whatnot. Yay. So I guess I don't have a hall sensor blown.

Patrick

 

[biohazardman]

Good deal cuz it's no fun tearing a motor apart mostly because there is no reason to put it back together without upgraded wires ect. and that's werq. Glad you got it figured out. Other than the guys on the forum that get together at EV gatherings around town, next one at Pioneer Square on the 9th of July, I have only seen a dozen or so ebikes in my near 7K of travel around the city.

 

[dogman dan]

A bad connection on the phase wiring would produce that exact symptom. Just a trickle would run slow, but it shudders if you pull any load. Same thing can happen if a nick in the wires at the axle cuts some strands, but leaves one or two connected.

 

[praskal]

@ biohazardman: I will try to make the July 9th EV day thing downtown this year. Though it's a Saturday so we very well may be out of town. What kind of ebike settup do you have?

 

[jimw1960]

Hello,

I have a Crystalyte RoadRunner Hub Motor (4825R) on 26" front Wheel. I use a 48V 10ah LiFePo4 pack. This has been working great for 2.5 years. While riding home from work last evening suddenly something bad happened. Power to the motor was decreased about 95%. The wheel will hardly move at all. There is a lunging/clicking sensation when I throttle the accelerator. I checked all the connections, and everything is fine. I turned off the controller for a while and pedaled. I then tried it again and it worked normally for a couple minutes, then it went right back into lunging/clicking and barely working. I have no idea what happened. Can anyone venture a guess??

Any help will be greatly appreciated.

Patrick

Interesting. I have the exact same motor/setup and experienced the exact same symptoms you describe at about the same time. Maybe all the Roadrunner motors are conspiring together. At first I thought the battery hit LVC, but the voltage is fine even under load. Then I thought maybe the heat because it was 102 in the shade yesterday. After letting it cool for an hour it seemed to be working fine. This morning, I'm set to go to work and right away it starts cutting out. Connections look good, so the controller and throttle are my next things to check. Let me know if the rewiring fixes yours and maybe I can start to look closer at my connections. If I figure out what is wrong with mine, I'll let you know.

 

[biohazardman]

@ biohazardman: I will try to make the July 9th EV day thing downtown this year. Though it's a Saturday so we very well may be out of town. What kind of ebike settup do you have?

Giant trace3 with a BMC v2 rear motor. Have done some larger phase wires and a V3 clutch on the motor, upgraded 8inch brakes and a long list of other mods for the bike. Started out at 48V running 60V a123 at the moment but in the middle of another upgrade to 66V. Links on the bottom of my post show it as well as the first build a GM DD 500W. Always good to see more show up at the events.

 

[jimw1960]

My problem turned out to be a cut wire on the throttle cable that was only making occasional contact. Respliced and good to go.

 

[praskal]

That is excellent that you found a simple a low cost reason for your problem. I'm taking mine in to the ebike repair dude tomorrow evening for a complete electrical system overhaul. Looking forward to it.

phr