I had an accident on my Giant Quick-e 2019

[Coolin]

So as the title says I had an accident on my bike.
Here's what happened - was cycling along about 12 miles an hour in eco mode. I needed to move into the next lane and go a bit faster so moved up a gear and changed to eco+ or normal on the controller. I then signaled because I was intending to turn into a right hand junction and suddenly I knew something was very wrong with the bike. it was as if it decelerated very quickly, like I'd braked (only I hadn't) and I had that moment of trying to stabilise the bike but knew I was going down anyway. So I hit the ground - probably fractured a rib but otherwise very bruised and sore for a few weeks.
The bike had some minor damage to the handlebar grips and weirdly the battery casing was broken (I discovered when I took it out the next day) at the bit where it fits into the frame, motor end.
But my real fear was that a motor malfunction had caused the accident. So I took it to the shop I bought it from. They examined the bike and sent the report to Giant. They examined the gear changer etc. and the motor. No errors were flagged up and I now have the bike back. The cause is still a mystery and I'm very reluctant to ride on it again. I will of course but my first few rides with it will be slow and cautious.
Any comments? Is it possible for a motor to cause this kind of thing? Are all errors with ebike motors flagged by the computer?
Cheers
Gillian

 

[Andy-Mat]

So as the title says I had an accident on my bike.
Here's what happened - was cycling along about 12 miles an hour in eco mode. I needed to move into the next lane and go a bit faster so moved up a gear and changed to eco+ or normal on the controller. I then signaled because I was intending to turn into a right hand junction and suddenly I knew something was very wrong with the bike. it was as if it decelerated very quickly, like I'd braked (only I hadn't) and I had that moment of trying to stabilise the bike but knew I was going down anyway. So I hit the ground - probably fractured a rib but otherwise very bruised and sore for a few weeks.
The bike had some minor damage to the handlebar grips and weirdly the battery casing was broken (I discovered when I took it out the next day) at the bit where it fits into the frame, motor end.
But my real fear was that a motor malfunction had caused the accident. So I took it to the shop I bought it from. They examined the bike and sent the report to Giant. They examined the gear changer etc. and the motor. No errors were flagged up and I now have the bike back. The cause is still a mystery and I'm very reluctant to ride on it again. I will of course but my first few rides with it will be slow and cautious.
Any comments? Is it possible for a motor to cause this kind of thing? Are all errors with ebike motors flagged by the computer?
Cheers
Gillian

Your exact and very valid question with regard to an e-bike, I cannot answer with 100% certainty.
But certainly ANY electric motor, whether DC, single Phase or even 3 phase, can suddenly be braked, by having a short develope across any or all of the power leads to the motor.
Its called "Dynamic Braking".
Even a partial short will still slow the motor down, but slower of course....
But as to that being what you experienced, I cannot say for certain, sorry.
But if it was, you could possibly see it again, sadly!
I really hope not.....and I hope that someone here can answer with 100% certainty of what the problem might be.....Worrying.
regards and I wish you a Happy New Year.
Andy

 

[Coolin]

That's interesting. It did feel like when you are driving and by mistake you go from say 5th gear to second gear and you have that sudden braking from the engine. It's whether this would give an error code or not.
And Happy New Year to you too

 

[Artstu]

Given the motor is a crank drive it would need a fault on the freewheel of the rear cassette to have any slowing effect on the bike.

 

[D C]

I wonder if there is a clue in your other post where you say "The percentages went down so quickly. When the battery went off it was like someone hit the brakes!"
could the battery have cut out for some reason?
The battery damage is a bit weird as you say, it shouldn't really have been damaged in that way in that sort of accident, I wonder if the damage to it could have somehow preceded the accident and be causing a momentary disconnection?
I'd suggest you get back on the bike for a few short rides as soon as you possibly can and keep hold of the handlebars, we've all fallen off at some point and it's easy to lose your confidence.
Sorry about the rib, extremely painful, don't catch a cold as sneezing is horrific!
Dave.

 

[Deleted member 25121]

As Artsu says, even if the crank motor and chain had jammed solid the freewheel at the rear would isolate them from the road wheel.

I wonder if there's a problem with your freewheel mechanism, if it jammed the motor would be driven by your momentum and that could cause all sorts of problems for the electrics.

 

[Coolin]

All these things are good to know. Thank you all
I have planned a ride with a friend next week. Along a canal path so should be safe - unless I fall in the canal !!

 

[soundwave]

All these things are good to know. Thank you all
I have planned a ride with a friend next week. Along a canal path so should be safe - unless I fall in the canal !!