My ebike shuts off when going over bumps, help please somebody!!

OLMECA

Finding my (electric) wheels
May 26, 2017
10
7
42
Richmond Hill, Ontario, Canada
So recently I just had my e-bike serviced at an e-bike shop about a week ago because one day I was on my way to work when all of a sudden my bike just stopped working. I ended up having to fold my bike up and cabbing it to work. Bringing my bike to the shop was the first thing on the list once I had a day off from work. It took a week for them to finally start working on my bike, I'm sure it only took an hour to fix it. So what happened was that the controller had blown out and all they needed to do was replace it with a new one that cost $89.00 plus 49.99 an hour for labor plus tax. So after $138.50 later I finally had my bike back. It's only been a week since I had it serviced but after one whole day of riding without any trouble, the bike has now started to completely shut off whenever I go over bumps no matter how big or small, the messed up part is that when I go over another bump, this causes the bike to turn back on. It's become so sensitive that it's so annoying, I can't even ride it on the sidewalk no more because of how bumpy it is, so I'm always riding on the smooth street but at times I'll hit a tiny bump that'll shut my bike off, and since it's very rare to come across another bump on the smooth road to turn it back on, I figured out another way to turn it back on, by shaking the handle bars back and forth until the LED lights turn back on and then I'm good to go. I probably have to shake the handle bar about 20 times when going to work just to turn my bike back on, and I just started to take notice that I look a bit crazy when people outside or in their cars passing me see me doing this to my bike. Anyone have any clue what it can be? I don't know where to look so even an opinion would be helpful. BTW the shop that serviced my bike is very far from where I live but if I can't troubleshoot this problem soon then that'll be my last resort.
 
D

Deleted member 4366

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Without knowing what bike you have, it's impossible to say. Show us some photos.
 
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D

Deleted member 4366

Guest
It's probably the battery contacts. You can get all sorts of problems with that type. The ones in the battery spread, so that they don't make good contacy. have a look at the gap in each one. It should be less than the thickness of the pins on the receiver. Also, the bit that holds the pins on the receiver can break or bend. make sure that the pins go into the slots properly.

After that, it can be any connection on the controller. To get at them, you need to take one side of the controller box. there's two screws in the side and a whole load of little bolts around it. Once the side is off, you can pull the controller out and check all the connectors. The two most likely faulty ones are the bullet connectors to the battery and the the three motor phase wires. Pull them apart, crimp the barrels to make them tighter and reconnect.

I'm assuming that you have a pedal sensor. If so, there's nothing on the handlebars that would stop it from working. If you only use the throttle, and you don't have a pedal sensor, then it could be that your throttle cable is damaged.

if you want any more help, post some photos. Don't be lazy. Anybody can understand "upload a file". It isn't difficult.
 

OLMECA

Finding my (electric) wheels
May 26, 2017
10
7
42
Richmond Hill, Ontario, Canada
It's probably the battery contacts. You can get all sorts of problems with that type. The ones in the battery spread, so that they don't make good contacy. have a look at the gap in each one. It should be less than the thickness of the pins on the receiver. Also, the bit that holds the pins on the receiver can break or bend. make sure that the pins go into the slots properly.

After that, it can be any connection on the controller. To get at them, you need to take one side of the controller box. there's two screws in the side and a whole load of little bolts around it. Once the side is off, you can pull the controller out and check all the connectors. The two most likely faulty ones are the bullet connectors to the battery and the the three motor phase wires. Pull them apart, crimp the barrels to make them tighter and reconnect.

I'm assuming that you have a pedal sensor. If so, there's nothing on the handlebars that would stop it from working. If you only use the throttle, and you don't have a pedal sensor, then it could be that your throttle cable is damaged.

if you want any more help, post some photos. Don't be lazy. Anybody can understand "upload a file". It isn't difficult.
Sorry don't mean to be lazy I was just getting ready for work so I didn't have time to figure out how to up loads things. I'll post some more pictures but thank you very much for your advice. Hopefully I could upload videos to show you how it shuts off and turns back on.
 
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spanos

Esteemed Pedelecer
Feb 18, 2011
250
64
My self and a colleague had this issue. Eventually, and I do mean eventually, both cases were a single broken weld between these cells.

Easy fix ie a large blob of solder..... But a right bugger to diagnose

It prob isn't this and poor contracts is far more likely. Worth bearing in mind all the same
 
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OLMECA

Finding my (electric) wheels
May 26, 2017
10
7
42
Richmond Hill, Ontario, Canada
Does your battery feel loose?
Nothing feels loose, everything looks in place, so I believe!? So I called the ebike shop that serviced by bike a few weeks ago and talked to one of their mechanics, I told them my problem and he said for me to try my best and carefully open up the frog case to get to the controller, he then told me to unplug each wire one at a time and spray it with contact spray and attach it back on firmly and tight. He said for me to do that to every wire. I opened it up last night and man was it a jungle in there, but once I purchase contact spray I'll give it a shot.
 
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OLMECA

Finding my (electric) wheels
May 26, 2017
10
7
42
Richmond Hill, Ontario, Canada
Here is a video that I uploaded on youtube because it wouldn't let me upload it on this site for some reason, sorry in advance I shot this video at night.

Sk7vNW5s

BTW I'm the only one outta of my friends and family that own an ebike so I really have no one to talk to when it comes to ebikes. I am so happy that I found this site, a community that revolves around ebikes and the best part is that my questions are met with plenty of replies. I can't wait to have more experience with ebikes under my belt so I'm able to answer questions on this site.
 
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JuicyBike

Trade Member
Jan 26, 2009
1,671
527
Derbyshire
Nothing feels loose, everything looks in place, so I believe!? So I called the ebike shop that serviced by bike a few weeks ago and talked to one of their mechanics, I told them my problem and he said for me to try my best and carefully open up the frog case to get to the controller, he then told me to unplug each wire one at a time and spray it with contact spray and attach it back on firmly and tight. He said for me to do that to every wire. I opened it up last night and man was it a jungle in there, but once I purchase contact spray I'll give it a shot.
Take a look at the battery contacts for signs of scorching.
 
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OLMECA

Finding my (electric) wheels
May 26, 2017
10
7
42
Richmond Hill, Ontario, Canada
I FIGURED IT YOU GUYS!!!!
Okay, the problem wasn't the wiring it was the Frog case. If you guys don't know the Frog case is what holds the battery and the controller mounted on the rear of a bike. Well, they have a reputation to crack in time and break apart, they are the worse. So because of this, the battery was being pulled out of its socket, and by me rocking the handle bars back and forth little did I know that it was this movement my ass would rock the seat causing the battery to be placed back on but not all the way.
 

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D

Deleted member 4366

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You need to make a pair of struts to support it. Use the 5mm screws in the side to mount the struts. You can get stiff aluminium tube from Wickes. Cut it to the right length then bash the ends flat with a hammer and drill holes for the bolts. Cut shorter lengths, bash them flat, drill holes in their ends and wrap them around the seat-stay to make a U-bracket to fit the lower end of the strut. Put a jubilee clip immediately below it to help stop it from sliding down the seat-stay.
 
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Deleted member 4366

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bracket.jpg Another thing: The plate that holds the connector is independent of the bracket that tears and is fixed to the plate that holds the battery, so the falling down of the battery has no effect on it. Instead, what happens is that it keeps getting knocked back when you push in the battery. To fix it, you have to get some heavy pliers and twist it back forwards until the pins are horizontal, being careful not to break the plastic bit.

You still need the struts to support the battery, or you need to weld some reinforcement onto the edges that crack/tear.
 
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