Bike suddenly has partial power

I have owned a 905 Torque from new and all of a sudden it will lose most of its power when cycling.

The battery level shows full but it feels like there's virtually no pedal assist. This happens on flat ground and I am not loaded up with shopping or anything heavy. I initially thought it may be the battery but the power indicator on the battery and the bike say otherwise.

 

I have tried turning off and back on again (IT Crowd) but this doesn't cure the problem.

 

Any tips greatly appreciated

 

Nick

Does yours have a throttle? If so, does it work OK?

Does yours have a throttle? If so, does it work OK?

 

Hello

 

Yes it has a throttle but makes no difference when the power drops.

 

Cheers

 

Nick

Did you check that the motor connector is in all the way to the line and not just in tight?

 

What caused the problem to start? What happened just before you first experienced it? Problems like this don't come from nowhere. Did you drop the bike, stick it in the boot of a car, fix a puncture or what?

Battery indicator lights mean nothing , could be the voltage collapsing.

First though check the controller phase bullet connections for burning/melting.

Did you check that the motor connector is in all the way to the line and not just in tight?

 

What caused the problem to start? What happened just before you first experienced it? Problems like this don't come from nowhere. Did you drop the bike, stick it in the boot of a car, fix a puncture or what?

No idea what caused the problem. hasn't been dropped or any of the other reasons you mentioned. It did come from nowhere.

I have taken some more diagnostic tests.

 

My bike has a torque sensor and when the power drops off it feels the same as when I stop pedalling, except it surges about every second.

 

Ive swapped over batteries (my wife's bike) and tried it again, still the same.

So its unlikely the battery, connectors all seem snug.

 

By trial end error I disconnected a plug from the controller one at a time and found when the orange 3 pin plug is disconnected the bike works fine.

 

So as I don't have to completely unwire the bike to find what it connects to does anybody know what this plug connects into?

 

Many thanks in advance

 

Nick

Throttle or brake sensor? No idea if a 905 Torque has brake sensors, but the problem you describe could be caused by one switching off and on at random. If it's unplugged the bike should work without it.

I have taken some more diagnostic tests.

 

My bike has a torque sensor and when the power drops off it feels the same as when I stop pedalling, except it surges about every second.

 

Ive swapped over batteries (my wife's bike) and tried it again, still the same.

So its unlikely the battery, connectors all seem snug.

 

By trial end error I disconnected a plug from the controller one at a time and found when the orange 3 pin plug is disconnected the bike works fine.

 

So as I don't have to completely unwire the bike to find what it connects to does anybody know what this plug connects into?

 

Many thanks in advance

 

Nick

 

Hi Nick,

 

That’s the throttle control. But for the power loss fault, send the controller in to us. I think a resistor needs changing.

 

All the best, David

Hi Nick,

 

That’s the throttle control. But for the power loss fault, send the controller in to us. I think a resistor needs changing.

 

All the best, David

Hello David

 

Thank you for replying.

What is the address to send it to?

Regards

 

Nick

Hello David

 

Thank you for replying.

What is the address to send it to?

Regards

 

Nick

 

Hi Nick,

 

please send it to…

Wisper Bikes

A7 Chaucer Business Park

Watery Lane

Kemsing

TN15 6NB

 

for the attention of David Miall

 

please put your return address and telephone number in the package.

 

reference “post 684577 Pedelecs”

 

All the best, David

Hi Nick,

 

please send it to…

Wisper Bikes

A7 Chaucer Business Park

Watery Lane

Kemsing

TN15 6NB

 

for the attention of David Miall

 

please put your return address and telephone number in the package.

 

reference “post 684577 Pedelecs”

 

All the best, David

Thanks David

 

I'll pop it in the post first thing.

 

Regards

 

Nick

I have a very similar problem.

I have a 2017 806 Torque that I bought a few months ago. It has been fine until about a week ago. Now, every now and again I will loose power. When it happens the controller stays and the battery level shows full, neither the throttle or the pedals provide assistance. After a few seconds it goes back to normal.

Any ideas?

I have a very similar problem.

I have a 2017 806 Torque that I bought a few months ago. It has been fine until about a week ago. Now, every now and again I will loose power. When it happens the controller stays and the battery level shows full, neither the throttle or the pedals provide assistance. After a few seconds it goes back to normal.

Any ideas?

 

 

Hi Richard

 

Since I started this thread David from Wisper (see thread) has asked me to send my controller in to be looked at.

At the same time I emailed Wisper directly and got a reply from their tech department.

Both alluded to a resistor inside the controller that may need replacing. My bike was out of warranty so removed the controller (front of battery box) to see if I could buy a replacement. These are no longer available so hopefully when I hear from David he was able to find the problem and repair it.

 

Failing that it's going to become an expensive piece of wall art!

 

I'll update you when I hear back from Wisper

 

Regards

 

Nick

I have a very similar problem.

I have a 2017 806 Torque that I bought a few months ago. It has been fine until about a week ago. Now, every now and again I will loose power. When it happens the controller stays and the battery level shows full, neither the throttle or the pedals provide assistance. After a few seconds it goes back to normal.

Any ideas?

 

hi Richard, could be the thermal cut out, do yih find this happens when hill climbing?

 

All the best, David

hi Richard, could be the thermal cut out, do yih find this happens when hill climbing?

 

All the best, David

Hi David,

Yes it happens going up hill, but sometimes very soon after starting a gentle slope and on short rides, only a mile or two.

I re-read the thread and noted [mention=3847]saneagle[/mention] said "Did you check that the motor connector is in all the way to the line and not just in tight?".

I took the rear wheel off a few weeks ago, which necessitated disconnecting the motor. I thought I had reconnected it properly but I disconnected and reconnected it a few days ago and have ridden the bike three times since then and there have been no more problems, so hopefully the problem is solved.

I re-read the thread and noted [mention=3847]saneagle[/mention] said "Did you check that the motor connector is in all the way to the line and not just in tight?".

I took the rear wheel off a few weeks ago, which necessitated disconnecting the motor. I thought I had reconnected it properly but I disconnected and reconnected it a few days ago and have ridden the bike three times since then and there have been no more problems, so hopefully the problem is solved.

 

The problem was in the controller unit. A resistor need replacing.

David from Wisper replied to this thread and asked me to send the controller unit to him. Wisper fixed it free of charge. Excellent service from Wisper.

I Don’t think they make that controller anymore so I would have been stuck without their help.

[mention=181]Wisper Bikes[/mention] I spoke too soon. It is now behaving pretty much like [mention=39654]northbourne nick[/mention] 's. Power cuts out. The display works, but no pedal assist and no throttle response. It will happen on the flat as well as uphill, sometimes within the first few seconds of starting a ride. Sometimes the battery level display is erratic when it happens. The last time I rode the bike the display went blank a couple of times when it happened.

Any suggestions on what to do?

[mention=181]Wisper Bikes[/mention] I spoke too soon. It is now behaving pretty much like [mention=39654]northbourne nick[/mention] 's. Power cuts out. The display works, but no pedal assist and no throttle response. It will happen on the flat as well as uphill, sometimes within the first few seconds of starting a ride. Sometimes the battery level display is erratic when it happens. The last time I rode the bike the display went blank a couple of times when it happened.

Any suggestions on what to do?

 

Please let me know what model you have and the age of the bike.

Please let me know what model you have and the age of the bike.

Hi,

It's a 2017 806 Torque

Thanks Richard,

 

Is it the original battery?

Thanks Richard,

 

Is it the original battery?

Yes, I believe so. I bought the bike second hand a couple of months ago. The person I bought it from had owned it since new. It hadn't been ridden much but the battery had been charged regularly.

Yes, I believe so. I bought the bike second hand a couple of months ago. The person I bought it from had owned it since new. It hadn't been ridden much but the battery had been charged regularly.

 

I would imagine that the battery needs replacing I'm afraid.

 

All the best, David

I would imagine that the battery needs replacing I'm afraid.

 

All the best, David

After reading up this morning and feared that would be the case. Will my local Wisper dealer be able to test the battery to confirm it?