Would appreciate a little shopper bike help

[Ray Winder]

I am not a serious biker but I have two e-bikes, one a halfords crossfire bought in 2017 and the second one a Tesco hopper shopper bought for my wife but unfortunately never used.
I am tinkering about with the shopper bike and wondered how the battery has faired after sitting about for some time.
So my curiosity has been awakened and I found out the charger then took the battery from its storage place in a polystyrene box in my garage, the charge LED was on the lowest level so I plugged it in and switched on, it seemed to take a while so I left it overnight. Next morning full power indicated by the LEDs and using my Fluke meter I read 29,2 Volts at the battery terminals.

Now keen to put it to the test I atempted to blow the tyres up, but unfortunately the valve stem of the front wheel is broken, so I ordered a new anti-puncture tyre with tube from E-bay, I need to spend some time cleaning the bike up while I await delivery

I know the crossfire bike needs 40nm torque on the wheel nuts but no idea for the shopper, I can't find the manual for the shopper, wondering if anyone has a copy or knows where I may get one.

I am curious how well it will work because it would be handy to put in the car and explore further afield.
I am considering battery upgrade options i.e. re cell or purchase a more powerful one if it seems viable.

 

[Nealh]

One can test the shopper with out a tyre, a simple static test will tell you if the bike works and if so one can also apply the brake at the same time to the motor wheel to see if the resistance causes any power issues with cutting out.

 

[Nealh]

For wheel nut tightness I just pinch them up tight and then give a good 1/4 to 1/2 turn.

 

[Ray Winder]

One can test the shopper with out a tyre, a simple static test will tell you if the bike works and if so one can also apply the brake at the same time to the motor wheel to see if the resistance causes any power issues with cutting out.

I cleaned the terminals and put the battery onto the bike then turned the key, nothing at first but a squirt of wd40 and working the key back and forward a few times the LEDs flashed then lit up I can select the assist level via the buttons, and pushing the peddle I feel the assist kick in. Found rather a strange issue, during storage in my shed wasps had started to make a nest under the seat, they left a mess under there.

Good news is my tire will be delivered today so I can do some cleaning up and a fell test soon as the weather allows.

 

[Ray Winder]

So cleaned up a few things, fitted new tyre and tube and tried it up and down the street a few times.
Key switch was a bit temperamental at first but the bike worked OK.
Ran up and down the slope few times probably about a mile. The battery LEDs go down to one when going up then back to full scale going down battery voltage was at 29.2 v when I first charged it and fel to 28.6 after a few runs up and down the road.
I think the battery if weak.
I would like to discharge and charge it a few times then check it. I wonder about using a power resistance across the terminals to do that.

 

[Nealh]

Though a bit weak, it didn't cut out. Once the SOC decreases then at some stage it will likely cut out on inclines.

 

[Ray Winder]

Though a bit weak, it didn't cut out. Once the SOC decreases then at some stage it will likely cut out on inclines.
[/QUOTE]
Yes it's not dead yet but I feel its on its way.
From what I gather re cell would be a bit expensive, so I'm looking at getting a new battery, there is one on ebay says yose power 24v 10 amp for £155.
Looking at Ali express there are various options.
Wonder if anyone has purchased one lately and could recommend?
I seem to remember someone changing to 36v battery and changing the controller wonder if that is a better option

 

[Hightechpete]

Take a look at this thread, might be of help.

City hopper throttle

Hi all, trying to help a friend install a throttle to his Tesco city hopper as he has mobility problems and can't always peddle. This bike has a pedelec system which works fine, but has no led/lcd control, it seems to be permanently on a mid range level of assist. The thumb throttle arrived...

www.pedelecs.co.uk

 

[Ray Winder]

That's interesting,
I thought this through and decided that without a decent battery the bike is useless but as this bike is a second bike then I don't was to go mad with it.
I am ordering a 24v 10 A battery to replace the existing one, I will try to cycle the old one a few times to see if it makes a decent backup.
If not then I will look into trying to replace the cell pack.

Interesting to note the battery still shows full on the LEDs built-in to the casing.

 

[Nealh]

An old tired battery will charge fully but once one puts a decent current load on it , the voltage will sag badly or collapse. The voltage then rebounds with no load.
All batteries will have some sag as this is normal, just with age the sag becomes greater and is no or evident when one has a proper voltage readout.

 

[Ray Winder]

Sadly that seem to be the story here, the LEDs on the control dipped dow to one when riding up the slopes, probably the best thing will be to take time and see what are the best options for a new cell pack and install it myself.
Might be an interesting little project.

 

[Nealh]

Depending on the case shape one can sometimes buy 18650 cells spot welded and then one is left to wire up the BMS and charge discharge ports.

 

[Ray Winder]

Battery is pretty small with a neat block of cells, probably given new cell advances it may be possible to improve the battery.
I don't see any BMS in there

 

[Nealh]

There will be one somewhere under the foam & shrink wrap.