Anyone in the Bournemouth area who can help fix my bike?

alexx44

Finding my (electric) wheels
Aug 18, 2020
6
0
Hello everyone,

My electric bike has started cutting out when I use it. I'm wondering if anyone will help diagnose the problem and is possible fix it in Bournemouth/dorset area. I'm happy to pay.

I'm defo not smart enough to do it myself, and really need help! There are no bike shops around here that do this kind of thing.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
19,991
8,173
60
West Sx RH
You may well have to learn to try and fix it we might be able to help you if you give us more info.
What type of bike or model/make ?
In what way does it cut out ? Over bumps, up hill or something else you can tell us.
Has something significant occurred recently whilst using the bike or even any minor insignificant event that may have occurred ?
 
Last edited:

oriteroom

Esteemed Pedelecer
Jul 13, 2008
297
110
as Nealh says, we need info on what bike etc... i’m local to you but woukd heed some info to provide any advice I have.
 

alexx44

Finding my (electric) wheels
Aug 18, 2020
6
0
@Nealh Hi guys! @oriteroom The problem started off not too bad. Only when going up one specific very steep hill. It has got slowly worse and now happens on every hill, with more and more frequency near the end of my journey. When the power cuts out, flipping the switch on the battery is the only way to restart, which makes me think the bms is cutting off the power. However I don't know how to trouble shoot, or how to investigate. If you can help. That would mean a lot. The bike is: https://www.e-bikesdirect.co.uk/brands/viking/viking-advance-electric-mountain-bike-grey I think it may be the motor, as the battery is quite new, and was recently checked by someone, but I may be wrong.
 

Benjahmin

Esteemed Pedelecer
Nov 10, 2014
2,460
1,675
69
West Wales
It sounds like a classic case of the battery not being able to supply the amperage that the controller/motor is calling for. Under heavy load conditions (high amperage) if the battery cannot produce quick enough, then the voltage will sag, maybe as far as lvc (low voltage cutoff). Then the bms cuts the power to protect the battery. A pause allows the volyage to recover sufficiently to aloow the power to come back on.
Either the battery is old and on it's last legs, OR the cells used do not have a high enough current delivering capacity for your system. It may show correct voltage when fully charged (41.5 -42v) but hasn't got the oomph needed.
What controller have you got?
What is the battery spec?
You say it's fairly new, where did you get it from?
The other option is that the controller is overheating and going into thermal shut down, this can take a few minutes to reset.
Where is the controller mounted? Can you touch it under shutdown conditions, to see how hot it is?
 

Benjahmin

Esteemed Pedelecer
Nov 10, 2014
2,460
1,675
69
West Wales
Ok, just looked at the spec, unfortunately it does actually say much. It looks like the controller will be in the base of the battery. Might be worth feeling around the base of the battery under shut down, to see if it's hot.
Does the motor have any markings on it?
Have you tried askin e-bikes direct what cells are in the battery? They may not know.
 

wheeliepete

Esteemed Pedelecer
Feb 28, 2016
2,047
755
60
Devon
If the bike runs fine on the flat at low power and only cuts out on hills on higher power levels, then as said, it is most likely the battery bms cutting the power. There could be several reasons for this. If you don't have one, buy a cheap DMM which will help diagnose the problem.
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,985
Basildon
@Nealh Hi guys! @oriteroom The problem started off not too bad. Only when going up one specific very steep hill. It has got slowly worse and now happens on every hill, with more and more frequency near the end of my journey. When the power cuts out, flipping the switch on the battery is the only way to restart, which makes me think the bms is cutting off the power. However I don't know how to trouble shoot, or how to investigate. If you can help. That would mean a lot. The bike is: https://www.e-bikesdirect.co.uk/brands/viking/viking-advance-electric-mountain-bike-grey I think it may be the motor, as the battery is quite new, and was recently checked by someone, but I may be wrong.
Those symptoms point to the battery at the end of its life or with other problems. You can only confirm that by testing with a meter. The first test would be to measure its voltage after you've fully charged it. That can tell us a lot.

How old is the battery? Do you know how many charges it's had or how many miles it's done?
 

alexx44

Finding my (electric) wheels
Aug 18, 2020
6
0
Hi there. Sorry for the slow reply. I am going to try replacing the battery. As I suppose it wouldn't hurt to upgrade anyway. How do I work out compatibility? Can anyone link me to an article about what voltage battery to get and all that stuff?
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,985
Basildon
It looks like your bike has the controller in the base of the receiver, which makes changing to a different type of battery tricky. It would be best would be to stick to the same type, given that you're not good at electrics. I'm not sure what they call that type, but you can probably find them on Ebay and Aliexpress.

From his other thread:
 

Wicky

Esteemed Pedelecer
Feb 12, 2014
2,823
4,011
Colchester, Essex
www.jhepburn.co.uk
From your link >

ELECTRIC FEATURES: 3 Mode Pedal Assist Display, 250W R/D Motor, 36V*8AH Battery, 4 Hour Charge, 40 Km Range* 25 km/h pedal assist /6km/h walking mode trigger

Have you contacted ebikes direct if they can supply a battery? alternatively there's a place in London that can recell it.
 
Last edited: