Help with fixing electric bike please

[Karim]

Hi all.

I bought a ebco ucr-10 second hand but didnt try it out as was in rush which is my mistake.

Now the problem with the bike is that when riding the motor will power on and apply the assist but when you come to a full stop and start again sometimes the motor doesn't kick back in and I am left struggling to take this heavy bike up hills on man power.

Once the motor kicks in and if the pedals continue to turn the power does not cut out snd will continue as long as I am turning the pedals.

The battery is a 36v 8.8ah Transx I believe.

I cant seem to understand what the problem is here all the lights are powering on the bike and showing fully charged battery.

Any help will be great.

Thanks

Karim

 

[Benjahmin]

Hi Karim,
So the motor cuts out when going uphill or starting from a standing start, is that right?

Do you know how old the bike/battery is?
Do you know when the bike was last regularly used before you bought it?

 

[Karim]

Im not to sure on battery age sorry as I bought it second hand but on the bars it shows its holding full charge.

It must be around a year or so old going by when the bike was released.

Also not to sure on usage from seller as didnt mention and my mistake not to ask as he wrote not used much thats all on advert.

The motor cuts out random to be honest doesnt depend on uphill or flat platform. For example when i pedal it kicks in and is fine whilst continuing to turn the pedals and ride but then when i come to a full stop and start pedalling again the motor doesnt wont to kick back in or if im lucky it just might kick back in.

Thanks for the help mate appreciate it

 

[Benjahmin]

It could be that the battery hasn't been used for a while or is old. It will show full charge (this is merely indicating voltage) but won't have much capacity, or cells could be out of balance. Try putting the battery on charge and leave it for a few hours after the led has gone green. This will help rebalance cells. If the battery is old or not been charged for an extended period, then it may not be recoverable, but could be re-celled.
Don't know if your bike is torque sense or pas. If it is pas it could be that. Can you post some 'photo's of the bottom bracket/chainring area?
In fact 'photo's of the whole bike will help.

 

[Karim]

Thanks for reply. I am hoping its a simple fix as a new battery is expensive and to re-cell im not sure how to.

Im sure I have charged it for longer than necessary as to try charge the battery for longer. Also I am currently making sure to charge every now and then to keep charge as I havent used it for a couple of months but following the information which states charge at least once every three months.

Please see this link for the exact bike and information from halford


http://www.halfords.com/cycling/bikes/hybrid-bikes/ebco-ucr-10-electric-bike

This is the bike but I am fearing as you say the battery could be the problem and in which case I will sell it for spares maybe.

 

[Karim]

 

[Deleted member 4366]

I would say that it's most likely a pedal sensor problem. Does it have a conventional one with magnet disc and fixed sensor behind the chain-wheel?

 

[Karim]

Hi thanks for message and yes it has the magnet disc and small sensor with a wire coming out behind the chain wheel as you stated. What should I look into getting done or fixed if this is the cause

 

[Deleted member 4366]

Check to see that the disc isn't loose so that it doesn't always turn with the crank. It's only held in place by friction. If it catches on anything, the fingers that hold it soon wear to make it loose. Also, check the gap between the disc and the sensor. It should be about 1 mm throughout the rotation. Sometimes the disc can get broken or knocked out of line when the chain comes off.

 

[Karim]

I will have a look tomorrow and see what I can find out from that. Thanks for the information appreciate it

 

[Karim]

Sorry I didnt get a chance to look at the bike yet. I did however as my uncle to check battery voltage which came up on his multimeter with the reading of 41.14V.

I believe the problem must be with the magnetic Pas but will try to take poctures shortly to update the thread. I really hope I can fix the bike with ease as I am not very good at diy repairs and technical in that sense

 

[Karim]

Hi sorry for not having the chance to check. Upong viewing the magnet PAS I can see the magnets are touching the sensor and can be seen to rub. The sensor part looks to be missing one screw at back and slightly moved.

Also the magnet part turns free if I touch it.

Do you think this is the problem?

How can I fix is as I wouldnt have a clue how to open the parts unless someone has a how to.

Can I replace with any parts or has to be same?

 

[Karim]

Some more images to show what might need to be opened

 

[Deleted member 4366]

The only questions are whether the touching dtops the disc from turning and how tight the disc is on its shaft. If you can rotate the disc easily by hand with the pedal still, something is wrong, or, likewise if you can see the disc catch on the sensor and stop rotatingwhile the pedal is turning.

 

[Karim]

The disc turns with the pedals but is easy to turn with the hand when pedals are held still. The rotation can be seen to have caused alot of rubbing on the magnetic disc.

Can I buy a new disc and sensor and chop the wires and refit if I can figure out how to do so?

Or does it need to be same parts only?

 

[Deleted member 4366]

It might be OK id you can slide it a bit sideways so that it doesn't touch. If it's too loose on the shaft, you have to take the crank off with a crank-puller and put a bit of insulating tape on the shaft or a bit of hot-melt glue on the disc centre to make it tight again.

 

[Karim]

Thanks for that. I ordered a tools to remove the crank part. I will keep posted on any updates.

Thanks for the help