I have owned electric bikes for 12 years

[fizzking]

Greetings,
I started off with a Thompson in 2004, which I had for 7 years. Sold it and bought a Powabyke shopper 6 speed in 2011.
I use it for local shopping, because it's quicker than driving/parking. In a race with a car I beat it home -approx 3/4 mile- by a minute or so, without breaking any laws such as one way streets or red traffic lights.
Having said that I own three cars, so I am in favour of both types of transportation.
I wonder whether anybody can offer advice?
My Powabyke has developed a fault. In cold weather it cuts off the power when I am in Power mode on anything less than a flat road. It requires the Ignition to be turned off and back on to provide any power. In warmer weather power is restored by pedalling.
The LED power indicators read Maximum at rest and drop to 1 or 2 (out of 4) bars on full throttle.
I don't think it's the batteries because I would expect a gradual decline not an abrupt stop.
Also I use the bike no more than one or twice a week, so the batteries have had 400 charges or fewer and I always charge after every ride, on a timer, to avoid overcharging.
Powabyke suggest a dry soldered joint. A Google search suggests a faulty throttle.
Help, please.

 

[flecc]

They have had a few throttle troubles, and a dry joint is always possible. However, since this has happened quite suddenly I suspect one or more cells of one of the batteries could have gone down. If you have a multimeter or DC voltmeter, check the voltages of the three batteries after a short run. You may find one markedly down on the other two.

If that's not the case, then try checking and remaking all of the battery terminal connections, since if one has gone high resistance it could cause this current drop problem.

And congratulations on being an early entrant to e-biking, there weren't many of us back then and those low price Thompson bikes were a common introduction path.
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[fizzking]

Thanks for the kind remarks and useful advice.
I have a multimeter, essential for my classic car.
However I did open the battery case and was bewildered by the complexity of the wiring. I had the impression that I would see 3 batts and 6 spade connectors. There is a lot of wiring, low and high amperage and all the batts have covers into which these wires disappear.
I tried to prise off one lid but was afraid to damage it, so it remained in place.
The wiring diag from Powabyke does not show anythiong more complicated than the batts and interlinks.

 

[flecc]

Once you prise off those covers you'll see the expected six connectors and their thick current carrying wires. The rest is just all the other wiring led through the battery box to keep it hidden and won't affect your battery voltage readings.

I'm not familiar with these later model Powabyke battery covers so not sure how they fit.
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[Cyclezee]

I wonder who was the first forum member to get an electric bike, could it have been Flecc?

 

[flecc]

I wonder who was the first forum member to get an electric bike, could it have been Flecc?

I don't know, but I very much doubt it was me. Despite over half a century of interest and involvement in assisted bikes, I resolutely cycled unpowered until August 2003 when I bought a Giant Lafree for assisted trailer pulling.

E-bike sales had started taking off in 1999 with the popular Yamaha PAS coming to Britain and the popular Lafree followed in 2001. Powabyke also rapidly expanded from their inception in 1999.

This forum started in October 2006 when I was its first member, so it's likely that at least one or two of the early members had bikes that pre-dated mine. And of course a few members have owned the petrol add-on motors of 1950 to the early 1980s, so were also assisted cyclists many years ago.
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[Cyclezee]

I'm a relative late comer, it was 2007 when I got my first Lafree and joined the forum shortly afterwards.

 

[fizzking]

They have had a few throttle troubles, and a dry joint is always possible. However, since this has happened quite suddenly I suspect one or more cells of one of the batteries could have gone down. If you have a multimeter or DC voltmeter, check the voltages of the three batteries after a short run. You may find one markedly down on the other two.

If that's not the case, then try checking and remaking all of the battery terminal connections, since if one has gone high resistance it could cause this current drop problem.

And congratulations on being an early entrant to e-biking, there weren't many of us back then and those low price Thompson bikes were a common introduction path.
.

I have had a look but there were problems
1. I could not remove the individual battery covers. They are secured by 4 screws, which look like Posidrive but are not. The closest I could see from my security driver bits was one called a Torq GR6, a 4 wing shape.
Unfortunately I could not use it because the screws are shrouded and the hex shank of the bit was too fat to go in.
2. I decided to test the voltage across the 3 batts, after a short ride. btw the Power LEDs were all over the place during the ride.
40.1Volts measured, which seems more than enough for 3x12V batts, so I assume the prob lies elsewhere. ( The voltage on my classic car was 13V, giving a fair degree of agreement)
3. The throttle cable disappears into the frame. 6 screws to remove the cover. There were 5 wires in the cable, Black, Red, Blue, Orange and Green. Presumably the first 3 for the throttle and the latter 2 for the power LEDs.
What now?

 

[trex]

treat yourself to a new e-bike?

 

[flecc]

Those shrouded special screws are a menace. I'm stumped on what to suggest trying next since it's still likely to be a connection problem.

The power LEDs wil often fluctate while riding, depending on how far the throttle is opened and how hard the motor is working. However, if the LEDs drop to almost nothing under high load shortly after a charge, that can still indicate one or more duff battery cells.

Maybe a Powabyke dealer can help, you'll find the information on locating them on this page.
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