Help! Urbanmover UM44 cuts out

[davedor53]

Hi everyone.
Newbie member, first posting.
Bought a UM44 Urbanmover (probably 10 years old, bit battered) recently for £300, and shortly after trouble free period the pedal assist cut out despite battery being fully charged. Stopped, switched off and on again and it went again, but any load put on it results in it repeatedly cutting out. All connections seem to be ok. Urbanmover tell me it's most likely old battery and they can refurb it for £320. Bit reluctant to do this as it may not solve the issue. Half a mind to sell it as it is for parts but would really like to solve this problem. Have any other members had similar issues with UM44 cutting out and what solutions they tried. Many thanks in advance. Dave

 

[sjpt]

It does sound as if battery is the most likely culprit, especially given its age. £320 seems expensive for 26v, 9ah.
If you can swap it yourself they advertise this for £257:

26V Cell Pack (Self Install)

26V Cell pack (UK assembled). This is the inner soft cell pack to enable suitably skilled customers to perform a simple swap to convert your old battery case into a brand new cell for years more use on your Urban Mover bike. Full instructions are provided. Model suitability includes all the...

urbanmover.com

I don't know if you can swap it for a generic 25v one (or more likely 24v).

 

[Nealh]

Knackered battery or one out of balance, what is the voltage reading fully charged ?

It is typical of an old battery to have the voltage collapse or sag horribly even when fully charged, when this occurs it is usually a sign of aging and ready for recycling.
10 years is a good life span for ebike battery.

 

[davedor53]

It does sound as if battery is the most likely culprit, especially given its age. £320 seems expensive for 26v, 9ah.
If you can swap it yourself they advertise this for £257:

26V Cell Pack (Self Install)

26V Cell pack (UK assembled). This is the inner soft cell pack to enable suitably skilled customers to perform a simple swap to convert your old battery case into a brand new cell for years more use on your Urban Mover bike. Full instructions are provided. Model suitability includes all the...

urbanmover.com

I don't know if you can swap it for a generic 25v one (or more likely 24v).

Many thanks sjpt, that suggestion would seem the best solution and cheaper too. cheers

 

[davedor53]

Knackered battery or one out of balance, what is the voltage reading fully charged ?

It is typical of an old battery to have the voltage collapse or sag horribly even when fully charged, when this occurs it is usually a sign of aging and ready for recycling.
10 years is a good life span for ebike battery.

Thaks for the reply - once connected to the charger for +12 hours battery reads fully charged - sorry no voltage reading, then just gives up on slightest incline. most likely issue is ageing battery and time to recycle. thanks for your time!

 

[sjpt]

Thaks for the reply - once connected to the charger for +12 hours battery reads fully charged - sorry no voltage reading, then just gives up on slightest incline. most likely issue is ageing battery and time to recycle. thanks for your time!

Yes. A dead battery will record full voltage after charge, it's just as soon as you try to draw any current from it it dies. So a voltage reading probably on the charged but unloaded battery probably wouldn't help.

 

[Nealh]

A voltage reading is the only sure way of knowing if a battery is fully charged, though likely the voltage is simply collapsing with any decent load. Led charge lights are only an indication.