Powabyke cuts out on full throttle.

bestyman

Finding my (electric) wheels
Sep 29, 2011
10
0
Hi all,

I`ve recently purchsed a Powabyke on ebay and I`m not happy.

It works ok , but when the throttle is fully open it cuts out, so when using it I only put the throttle on half to 3/4.

I thought the batterys may be the problem so replaced them .

The problem still occours with the bike on its stand, so load is not an issue.

Any suggestions of possible faults and how to check would be appreaciated.

Thanks

Mark
 

bestyman

Finding my (electric) wheels
Sep 29, 2011
10
0
Hi,
Its a Powerbyke euro 6 speed. The seller states that it is two years old.

Don`t know if this is relevant, but there are no wires going to the left hand brake lever, it seems like they have been cut off but I am not sure as I have nothoing to compare it to.

The problem is there if the key is in 1 or 2 position.

Cheers
 
D

Deleted member 4366

Guest
The brake wire being cut off shouldn't be a problem as long as the wire to the controller and its connector were removed to avoid the cut ends shorting out. If the bare ends touched, that would cutoff your power, but it wouldn't be related to the thottle. My guess is a faulty throttle - possibly a magnet dislodged. You can get a new throttle from Ebay. If you want to test that its not a controller problem, you can get a 10k linear potentiometer from Maplin. Wire the red and black throttle wires to the outer two connections and the other wire (green, or white normally) to the middle connection. When you turn the shaft , it should work just like a throttle.
 

bestyman

Finding my (electric) wheels
Sep 29, 2011
10
0
Thanks for the help. It would seem none on ebay for the search "powabyke throttle" or "Euro bike throttle".
I did find one online though for £35. Is this a fair price?
Cheers
 
D

Deleted member 4366

Guest
Thanks for the help. It would seem none on ebay for the search "powabyke throttle" or "Euro bike throttle".
I did find one online though for £35. Is this a fair price?
Cheers
No, they cost about £2.50 from BMSbattery.com. You don't need a Powabyke throttle. They nearly all work on the same principle. Some throttles have LED battery indicator lights in, some have an on/off switch. Could you describe yours and tell us what voltage your bike is and I'll find you a throttle? Before buying a new one, you should do the Potentiometer test. You can get one for about £1.5 from Maplin. Do you have any electrical knowledge?
 

bestyman

Finding my (electric) wheels
Sep 29, 2011
10
0
Thank you for the links.
Because the throttle is only £8 , I think its worth a punt without testing first ( I`m lazy).

I`m by no means an electrical engineer, in fact I`m a plumber but I do own a multimeter and can follow a wiring diagram , so should be ok with this one.
 
D

Deleted member 4366

Guest
Thank you for the links.
Because the throttle is only £8 , I think its worth a punt without testing first ( I`m lazy).

I`m by no means an electrical engineer, in fact I`m a plumber but I do own a multimeter and can follow a wiring diagram , so should be ok with this one.
It looks like some that I bought. If it's the same, you have to be careful.. They're not very strong. If you go over a bump while holding full throttle, they break.. I've broken three of them like that, so I use thumb throttles now.
It'll at least be ok to see if it fixes your problem. let us know how you get on. Incidentally, can you get full power with the pedal sensor?
 

bestyman

Finding my (electric) wheels
Sep 29, 2011
10
0
I dont know what you mean by pedal sensor, but I still have the same problem when the key is in position 1 or 2. ( hope that makes sense)
 
D

Deleted member 4366

Guest
I dont know what you mean by pedal sensor, but I still have the same problem when the key is in position 1 or 2. ( hope that makes sense)
Most electric bikes have a sensor on the crank so that when you pedal, the motor gives power without using the throttle. I just looked at the manual for the shopper and it seems that it doesn't work like that. Instead, the pedalling enables the use of the throttle. Is yours the same? if not, how does it work?
 

bestyman

Finding my (electric) wheels
Sep 29, 2011
10
0
The key has 2 positions. In position 1 the bike can be used without pedaling, although you do have to pedal once to get started.
In position 2 the motor cuts in when you pedal but the rider still has to twist the throttle.

In position 2 I still get the same problem in that if I open the throttle fully I get no motor assistance at all.
 

bestyman

Finding my (electric) wheels
Sep 29, 2011
10
0
The throttle arrived and I fitted it and pleased to say that the throttle was the fault ( never realised it was so fast), but I still have one small issue.

When the throttle is in the off position the bike goes at full speed and when the throttle is on full the bike stops. I assume that I have a wire crossed somewhere.
I have
red to red
green to green
and the middle wires are black to yellow.

Any info on what wire should go where or if not what I should be checking for with a meter.

Thanks again
 

NRG

Esteemed Pedelecer
Oct 6, 2009
2,592
10
I'd try and swap the green and yellow over...
 

bestyman

Finding my (electric) wheels
Sep 29, 2011
10
0
Im still stuck here.

From the bike I have red yellow and green. From the thtrottle I have red yellow and black.

So far combinations I have tried are:

BIKE RED - G B R G R B
BIKE YELLOW - R R B B G G
BIKE GREEN - B G G R B R

As far as I know there are only 6 possible combinations and I have tried them all?

The only combinations that does anything is Y - Y
R - R
G - B

Any ideas please?
 

bestyman

Finding my (electric) wheels
Sep 29, 2011
10
0
A thumd throttle was mentioned earlier, would this solve the issue and where do I get one from please?

Any suggestions at all apreaciated, Im going away this weekend!
Thanks
 
D

Deleted member 4366

Guest
If the throttle is working in reverse, I don't believe that changing the wiring will fix it, because the hall sensor in the throttle only accepts 5v on one pin and 0v on another, and the third gives the return signal. The return signal depends on magnetism at the hall sensor. There's a lot if different hall sensors that behave in different ways. To get yours working the correct way, you'd need to change the magnets from N to S and vice versa: There's normally two magnets in a throttle, although some have a magnetic strip (can't be changed) and some only have one magnet.. Nearly all ebike throttles work the same way: i.e. when the throttle is closed, they give a low voltage and when they're open, they give a higher voltage. It's possible that your original throttle works the other way round. You'd have to test it by applying 5v between the red and black wires and measuring what happens on the third pin when you open the throttle. It's also possible that your new throttle has been put together wrongly, so you'd need to do the same check. Whatever the problem, you can fix it by turning the magnets over (if possible). You'd have to open the throttle to see what's inside. For that, you need to remove it from the handlebar first. Buying another throttle might or might not fix your problem. You'd need to do the above tests to determine that. Most mobile phone chargers are 5v (Check the writing on the charger) so you can use one of them or USB chargers or anything like that, or 3 AA cells for 4.5v would work.
 

bestyman

Finding my (electric) wheels
Sep 29, 2011
10
0
Thank you very much for the info.

I took the throttle apart andchanged the 2 magnets around and now the throttle works. I since realised that the bike does not reach full power so I must have put one of the magents in wrong. I will have another go at it later, at least I know what the problem is now.
 

sheryck

Finding my (electric) wheels
Sep 16, 2011
10
0
East Riding of Yorkshire
Just had the same problem and sorted it thanks to this thread and d8veh. The magnets were both south on the faces towards each other (used a compass). Marked them, pried them out and super-glued them back in with north facing north. Also for info, red wire to red, green to green, and black to yellow.