Powabyke starting to play up :-(

[ady347]

Hi, I have a very intermittent problem starting with my bike. when riding on motor only or pedal assist the motor is cutting out and straight back in again, it does it a couple of times every few minutes. The battery indicator goes back up to full briefly when motor cuts out. I have done a diagnostic check but none the wiser at the minute. I may have to wait until it fails completely before I can investigate further. All I have done is check battery voltage and it seems fine. Just wondered is their any common faults with these bikes.
It's a 24 speed (called a euro I think? The model that has the sla batteries fitted between your legs.

unfortunately without this bike I would have no transport so I'm hoping it is not going to be anything too serious

 

[jackhandy]

This is probably nothing to do with your problem but, for what it's worth;

My missus' Powabyke x6 has a beefy brushed motor, like yours I believe: On a prolonged uphill the battery voltage sags & sometimes goes below the controller's Low Voltage Cutoff. This should be 31v, but hers cuts off at 33.5v.

Whether this applies to SLA batteries, I know not.

 

[ady347]

Yeah I believe it's same motor, my journey home is 9 miles with some hills and I pedal assist all the way home and its pretty flat by the time I get their! The batteries are Lucas 12ah and only 4 months old. But they do get charged 10 times a week!

My fault is doin it with fully charged batteries which register 40.05v fully charged

My bike

 

[shemozzle999]

Have a look at this old thread:

http://www.pedelecs.co.uk/forum/electric-bicycles/6433-powabyke-breakdown-help-sought.html#post82002

 

[Deleted member 4366]

40.5v seems a bit low. You need to open up the case and measure the three batteries separately. Do it when they're hot off the charger, and after the cutting-out before charging.

 

[ady347]

Thanks for that, I will test each battery tomorrow. It starts cutting out even when batteries are fresh off charge.

 

[johnc461165]

I have 2 powabykes and on both of them I have a bungee cord wrapped around the battery up near the controller because I had the same problem as you. The battery can bounce away from the contacts and cut off power momentarily. I hope that this is some help to you. John

 

[ady347]

Hi thanks for advice, when the motor cuts in and out the led lights do not go off. they go from say half to full when motor cuts out , then back to half when motor kicks back in.
This motor cutting in and out happens in a split second and can do it about 3 times in one minute. Then it can be fine for 5 mins and do it again. When I purposely go over bumps it doesn't make the bike do it, it can do it on smooth Tarmac.

I have charged batteries and the total voltage was 40.2.

Battery 1 is 13.2v
Battery 2 is 13.3v
Battery 3 is 13.3v

Like I say they are Lucas 12v 12ah approx 4-5 months old and have been recharged around 120 to 140 times estimated

 

[oigoi]

I think the lights surging up to full is indicating that the power going to the motor is being cut. This would create sudden rise in voltage in the system before the motor because the power that was going to the motor suddenly has nowhere to go.
Therefore possible faults I can think of might be a loose connection or damaged wire between the controller and the motor, or a brake switch playing up, got to be something that shuts off power to the motor very suddenly to make the voltage rise the way it is.

 

[ady347]

Ok thanks, I wondered throttle possibly? The only thing I have found is that when you pull break levers (either) should the motor cut out? As it doesn't

 

[oigoi]

Do your brake switches have electrical wires going to them or just the brake cables?

 

[ady347]

They just have a cable wrapped in a white protective plastic,I followed the cable and it just goes to brakes, no wires going off to controller.
Back to work tonight for 4 nites so the next 80 miles could be fun!

 

[shemozzle999]

Hi ady347,

Another old thread:

http://www.pedelecs.co.uk/forum/electric-bicycles/11367-powabyke-carbon-brushes.html#post136849

Members photo showing known problem battery connectors:

http://www.pedelecs.co.uk/forum/gallery/showimage.php?i=225&c=9

It could be worn down brushes or brushes could be sticking in their guides, it might be worth giving them a clean.
I would also recheck your internal battery leads - give the push on connectors a firm wiggle to make sure they are still crimped tight on the wires.

Or try and get in touch with the contact member mentioned in the thread.

I hope this helps.

 

[johnc461165]

I have some internal motor photos if you need them.

 

[ady347]

Hi appreciating the advice. It certainly played up more on way to work tonite. Then it can be fine for 10mins. I will check all connections tomorrow, if I have a battery terminal issue would the led lights not go off intermittently?
I am keen to strip motor and do a regrease and inspection but even though I am competent not sure how to dismantle it.

 

[103Alex1]

The only thing I have found is that when you pull break levers (either) should the motor cut out? As it doesn't

Personally wouldn't ride the bike or until you sort that ... if the throttle sticks or breaks you may not be able to stop the bike. Could be messy, painful and/or expensive (!) Brake cutoff switches are a fundamental safety issue - all eBikes should have working ones ... can mean difference between life and death in an emergency situation.

Unfortunately don't know whether you have one on that model and it's not working (seems odd that there's no wiring run to the controller) or you don't have one - in which case I'd make it a "must do" priority to fit one. I'm sure someone who knows or can find out will tell you.

 

[ady347]

It's an original untampered with bike for sure. The guy I had it off used it about 3 times. It still had the bobbly bits on tyres. The pic I attached before was how I got it like brand new.
I have 3 wires coming out speed controller. 1 to motor, 1 to pedal sensor and 1 to throttle. Their are no additional holes in bottom of controller where any other wires can go in. The cables from brake levers on handle bars are deffo just cables no wiring.
I also read about some have motion sensors on back wheel? But I can't see that on mine either

 

[ady347]

Be a bit lost without bike, I live 9 miles from work, I work nites too! No buses, couldn't afford taxis. Cannot drive now due to medical reasons, got a young baby so can't rely on wife to ferry me round.

All good fun! Can't complain though when the bike goes wrong I owe alot to this bike!

 

[103Alex1]

There will be a fix for it I'm sure if it's not set up right or not working. Appreciate your position - be good if the members who can help out technically are able get you safe again ASAP, especially with those responsibilities at home !

This is a step-thru - but specifically refers to 2 cables coming from brake levers, one for motor cutoff and the other for braking @ 0m27 on the Powabyke. Thought it might help. Does yours have 2 cables from each brake lever (or either brake lever) ?

electric bike top speed. Legal UK limit experiment.PowaByke Shopper with detailed walk around. - YouTube

Haven't seen one of these bikes so it's very hard to 2nd guess, but just applying basic logic based on what you've said about the cable routings to the controller, I'm just wondering whether the signal for brake cutoff runs from the brake levers but through the same wiring housing that also carries the throttle wires to the controller. They both originate from more or less the same area of the bike. On some systems I believe it's just a single signal wire that needs routing to the controller so that's probably not impossible for manufacturer to design in. Just a thought.

 

[johnc461165]

Hi ady, just to clear up a few points, the brake levers on this model do not have cut out switches, I have 2 of these bikes and they are both the same regarding switches, the older model has a rotation sensor on the back wheel but the newer model like yours does not. Does the cutting out occur in both pedal assist, and throttle only, if it only happens in one mode it could be the key switch contacts. The motor is not difficult to open up and only requires basic tools, phillips screwdriver and a spanner but I doubt whether you problem lies there. John