36V Powabyke. Help required please with motor issue.

[Mr.Linnet]

Got a reply from saneagle a couple of days ago in the welcome section ( see copy attached )

Been checking over the Powabyke ( photo attached ) that I recently obtained. Checked the batteries and battery box, all ok. Got three full bars of power illuminating when I turn the throttle key on, however when I turn the throttle you can hear the motor working but its not turning the wheel.

I thought I might have some success as I had already tried a fully charged 12V heavy duty car battery on the front wheel (connected directly to the red and black wires on the motor after dis-connecting them from the wires that go to the controller ) and the wheel did spin albeit slowly.

I have tried to attach a couple of short 5 second video clips to help show what I have just written but the video format is not recognised in the attachment drop down box

Would appreciate some help and assistance as to what I should do next please

 

[saneagle]

Got a reply from saneagle a couple of days ago in the welcome section ( see copy attached )

Been checking over the Powabyke ( photo attached ) that I recently obtained. Checked the batteries and battery box, all ok. Got three full bars of power illuminating when I turn the throttle key on, however when I turn the throttle you can hear the motor working but its not turning the wheel.

I thought I might have some success as I had already tried a fully charged 12V heavy duty car battery on the front wheel (connected directly to the red and black wires on the motor after dis-connecting them from the wires that go to the controller ) and the wheel did spin albeit slowly.

I have tried to attach a couple of short 5 second video clips to help show what I have just written but the video format is not recognised in the attachment drop down box

Would appreciate some help and assistance as to what I should do next please

Upload the videos to Youtube and post a link.
The motor will run at 1/2 the max speed with 12v if it's a 24v motor and 1/3 the speed if its a 36v one.

 

[Mr.Linnet]

Upload the videos to Youtube and post a link.
The motor will run at 1/2 the max speed with 12v if it's a 24v motor and 1/3 the speed if its a 36v one.

Thank you very much for your reply, however, I believe I have managed to resolve the issue.

I dis-connected the red and black motor wires from the junction box again and tried 12V directly into the motor ( see photo 1 ) again. The wheel turned in the direction of the arrow I had drawn on the wheel beforehand to remind me which direction the wheel should turn. I tried 24V and then 36V. The wheel spun correctly on all three attempts getting quicker every time.

I put the red and black wires back into the junction box and fitted the battery box back onto the bike. Switched on the power button, 3 bars illuminated on the throttle switch but when I turned the throttle the wheel stayed stationary but a noise of something attempting to move getting faster and then slower came form the hub as I increased and decreased the throttle movement ( see photo 2 )

With the power light still illuminated I placed a meter across the red and black wires in the junction box whilst twisting the throttle. Much to my amazement I was getting a minus reading of around 36V.

I reversed the wires feeding into the red and black motor wires and bingo the wheel rotated correctly in the direction of the arrow. It sped up and slowed downed in accordance with my throttle movement.

Carried out a road test, everything working fine.

The one thing I am concerned about is the cracks in the motor casing ( see photo 3 ). I did remove the motor from the centre hub when I first got the bike to check inside before electing to leave well alone for the time being. Are the cracks something I should be concerned about?

Many thanks

 

[saneagle]

Thank you very much for your reply, however, I believe I have managed to resolve the issue.

I dis-connected the red and black motor wires from the junction box again and tried 12V directly into the motor ( see photo 1 ) again. The wheel turned in the direction of the arrow I had drawn on the wheel beforehand to remind me which direction the wheel should turn. I tried 24V and then 36V. The wheel spun correctly on all three attempts getting quicker every time.

I put the red and black wires back into the junction box and fitted the battery box back onto the bike. Switched on the power button, 3 bars illuminated on the throttle switch but when I turned the throttle the wheel stayed stationary but a noise of something attempting to move getting faster and then slower came form the hub as I increased and decreased the throttle movement ( see photo 2 )

With the power light still illuminated I placed a meter across the red and black wires in the junction box whilst twisting the throttle. Much to my amazement I was getting a minus reading of around 36V.

I reversed the wires feeding into the red and black motor wires and bingo the wheel rotated correctly in the direction of the arrow. It sped up and slowed downed in accordance with my throttle movement.

Carried out a road test, everything working fine.

The one thing I am concerned about is the cracks in the motor casing ( see photo 3 ). I did remove the motor from the centre hub when I first got the bike to check inside before electing to leave well alone for the time being. Are the cracks something I should be concerned about?

Many thanks

It doesn't look good, but there's not much you can do about it. spares are pretty rare these days. I'd live with it. Maybe check after a few hundred miles to make sure they're not getting worse.

 

[Mr.Linnet]

It doesn't look good, but there's not much you can do about it. spares are pretty rare these days. I'd live with it. Maybe check after a few hundred miles to make sure they're not getting worse.

Thank you very much for your interest in this thread and for the content of your replies. Greatly appreciated.

 

[WheezyRider]

If funds permit, think about upgrading to a modern brushless motor and a lithium battery. It significantly improves the bike. Much lighter and longer range and quieter. That's what I did with mine. Also, as it is pre 2016, you can keep the throttle and comply with the rules. I have an original Powabyke motor in my spares pile, but it is a rear motor. If you are worried about the cracks you could fill them with epoxy, or even do some aluminium brazing with a blow torch.

 

[Mr.Linnet]

If funds permit, think about upgrading to a modern brushless motor and a lithium battery. It significantly improves the bike. Much lighter and longer range and quieter. That's what I did with mine. Also, as it is pre 2016, you can keep the throttle and comply with the rules. I have an original Powabyke motor in my spares pile, but it is a rear motor. If you are worried about the cracks you could fill them with epoxy, or even do some aluminium brazing with a blow torch.

Thank you very much WheezyRider for your reply and for the advice and suggestions you make, much appreciated.

I wanted to experiment and learn from something cheapish. A bit like learning to walk before you can run scenario especially with my very limited electrical knowledge. I am ok with mechanical stuff but anything to do with electrics is very basic.

A brushless motor project was my next aim

I do have a couple of follow on questions from your comments though which I am hoping will help me in the future.

You mention because its pre 2016 I can keep the throttle. I thought I read somewhere that a throttle for a brushed motor ( as fitted to my Powabyke ) would not be compatible with a brushless motor. Have I misunderstood the article I was reading?

Does a brushless motor need to be connected via a Hall sensor in order to work? ( I have recently seen a 48V 1000W Voilamart electric hub for sale locally but its just the hub and need spokes ).

Many thanks in anticipation

 

[WheezyRider]

Thank you very much WheezyRider for your reply and for the advice and suggestions you make, much appreciated.

I wanted to experiment and learn from something cheapish. A bit like learning to walk before you can run scenario especially with my very limited electrical knowledge. I am ok with mechanical stuff but anything to do with electrics is very basic.

A brushless motor project was my next aim

I do have a couple of follow on questions from your comments though which I am hoping will help me in the future.

You mention because its pre 2016 I can keep the throttle. I thought I read somewhere that a throttle for a brushed motor ( as fitted to my Powabyke ) would not be compatible with a brushless motor. Have I misunderstood the article I was reading?

Does a brushless motor need to be connected via a Hall sensor in order to work? ( I have recently seen a 48V 1000W Voilamart electric hub for sale locally but its just the hub and need spokes ).

Many thanks in anticipation

That's a really good way of getting into e-bikes, pick up an old cheap bike and experiment. You will learn a lot.

The Powabyke was a terrible bike, BUT, it was of its time and a pioneer for e-biking in this country. With a little modernisation it can be made into a good utility bike.

I would not put a 1000W kit on the front wheel of any bike if that is your intention. First of all, 1000W is illegal and there is no arguing against that if caught. Second, so much power on the front wheel is a bad idea. Even with a 250W motor on a front wheel in slippery conditions can be challenging when cornering.

If you get an up to date brushless kit, it will probably come with a throttle, so I wouldn't worry about re-using the old one. I found a thumb throttle much better than a twist throttle, which used to give me a pain in the wrist on long journeys.

 

[Mr.Linnet]

That's a really good way of getting into e-bikes, pick up an old cheap bike and experiment. You will learn a lot.

The Powabyke was a terrible bike, BUT, it was of its time and a pioneer for e-biking in this country. With a little modernisation it can be made into a good utility bike.

I would not put a 1000W kit on the front wheel of any bike if that is your intention. First of all, 1000W is illegal and there is no arguing against that if caught. Second, so much power on the front wheel is a bad idea. Even with a 250W motor on a front wheel in slippery conditions can be challenging when cornering.

If you get an up to date brushless kit, it will probably come with a throttle, so I wouldn't worry about re-using the old one. I found a thumb throttle much better than a twist throttle, which used to give me a pain in the wrist on long journeys.

Many thanks for your prompt reply and the information you supply.

I never had any real intention of buying the 48V 1000W hub, I was only using that as an example of what was available locally. I wanted to know your thoughts on the way to proceed next and whether something like this unit would be viable.

I can`t justify spending hundreds of pounds on buying an electric bike, I need to learn and build something suitable for my needs and finances.

I have road tested the Powabyke and it goes reasonably well. My wife also tried it and liked the idea of perhaps using one for her daily commute to work ( weather permitting ). The only issue/comment she had with the Powabyke was the width of the frame complete with battery pack whilst trying to pedal. I perhaps need to look for something that has a battery pack situated behind the seat, whether it be on the frame or on a rear carrier. Any suggestions on models to look for gratefully accepted

Without getting too carried away, I was thinking of powering the next project with a couple of 18V battery drill batteries. I`m assuming thats feasible?

 

[WheezyRider]

I can understand, the last thing you want to do is spend a lot of money on something you have yet to get to grips with and have yet to find out what suits your particular needs.

I'm sure there are loads of people on here who can suggest good low cost or second hand e-bike models to meet your wife's needs, or bikes that can be converted with kits.

The use of 18V drill batteries in series has been done, but you will probably find buying a 36V battery more practical in the long run. Expect to pay about £180 to £190 for a reasonable 15Ah lithium pack you can mount on the down tube:



With the Powabyke, the wide central battery bay does allow you to build an enclosure for different battery types. I made a plywood box to replace the lead acid packs and then I could put a wide range of different batteries into it. The bike has been a useful test bed for me due to its flexibility.

I'm not sure on your Powabyke, but mine being a rear wheel drive, it did have a 155 mm OLD on the back - so quite a large space between the rear forks. This made it ideally suited to the Voilamart 250W rear kit, but I had an accident and blew that motor, then the prices of those kits went way too high for what they were worth. I found I could fit a standard 135 OLD wheel into it as the frame being steel, it would bend as needed, but I just had to be careful when unbolting the wheel. The large battery bay does mean that the chain line is quite far out, especially when using low gears. However, as I have a throttle, I normally just leave it in top gear and pull away with the throttle.

 

[Mr.Linnet]

Thank you very much WheezyRider for your continued help and interest in this topic. I am very grateful to you for taking the time to reply to my posts and for the details/information you supply within your replies.

 

[saneagle]

Thank you very much WheezyRider for your continued help and interest in this topic. I am very grateful to you for taking the time to reply to my posts and for the details/information you supply within your replies.

the Powabyke Euro is not bad at all apart from it's weight. Its motor gives very good torque, so it's weight is tolerable. The only sensible upgrade to that bike is to change the battery from lead to lithium, which saves a lot of weight and makes the bike generally more pleasant to ride.

You can't fit any 36v lithium battery. You need one that can give high current, otherwise it will keep cutting out. I can't remember how much current the Powabyke uses, but I know it's at least 20 amps. If you decide to upgrade to lithium, it might be an idea to check the current first with an Ebay wattmeter, so that you can get a battery with the necessary discharge rate.

 

[WheezyRider]

the Powabyke Euro is not bad at all apart from it's weight. Its motor gives very good torque, so it's weight is tolerable. The only sensible upgrade to that bike is to change the battery from lead to lithium, which saves a lot of weight and makes the bike generally more pleasant to ride.

You can't fit any 36v lithium battery. You need one that can give high current, otherwise it will keep cutting out. I can't remember how much current the Powabyke uses, but I know it's at least 20 amps. If you decide to upgrade to lithium, it might be an idea to check the current first with an Ebay wattmeter, so that you can get a battery with the necessary discharge rate.

I mostly agree with you there, the existing motor is not bad, but a modern brushless motor is a lot lighter, more efficient and less noisy. But as you say, the starting point is the battery, especially if funds are limited.

 

[saneagle]

I mostly agree with you there, the existing motor is not bad, but a modern brushless motor is a lot lighter, more efficient and less noisy. But as you say, the starting point is the battery, especially if funds are limited.

It depends what you want. The powabyke motor is no bigger and heavier than any high torque motor. It can get heavy riders up quite steep hills without pedalling. The lighter modern brushless ones you're thinking of can't do that.

It wouldn't make sense anyway to change the motor. You'd have to change the controller and controls too, then why would you want to save a small amount of weight in the motor, when most of the weight is in the battery and massive frame that holds the battery. With that amount of expense, it would make more sense to get a £10 donor from the scrap man and fit a normal ebike kit to it. while as just changing the battery for a pair of 8AH 5S lipos with monitors would be about £100 and would be a massive improvement.

 

[WheezyRider]

It depends what you want. The powabyke motor is no bigger and heavier than any high torque motor. It can get heavy riders up quite steep hills without pedalling. The lighter modern brushless ones you're thinking of can't do that.

Hmmm, I'm not so sure. My Powabyke motor was close to 6 kg. It was a beast of a motor. The brushless motor I replaced it with was around half that. It had no problems getting the bike up steep hills, even though it was low torque. I did improve it by eventually running that one at 48V, which made hill climbing a breeze. Currently it has a Yose Power 250W front motor, (about 35 Nm I think) running at 36 V and it runs fine, even if I don't pedal. With the updates I did to the to the bike, I easily took 10kg off the weight of the bike, which may have helped.

But, so long as it is working fine, he may as well stick with the original motor for now and focus on the battery. If those cracks get worse, or the brushes go, then it will be time to think about the motor update

 

[Mr.Linnet]

It depends what you want. The powabyke motor is no bigger and heavier than any high torque motor. It can get heavy riders up quite steep hills without pedalling. The lighter modern brushless ones you're thinking of can't do that.

It wouldn't make sense anyway to change the motor. You'd have to change the controller and controls too, then why would you want to save a small amount of weight in the motor, when most of the weight is in the battery and massive frame that holds the battery. With that amount of expense, it would make more sense to get a £10 donor from the scrap man and fit a normal ebike kit to it. while as just changing the battery for a pair of 8AH 5S lipos with monitors would be about £100 and would be a massive improvement.

Thank you very much for your reply and the comments you make. Its given me something to ponder on. I also need to do some research, your part comment "while as just changing the battery for a pair of 8AH 5S lipos with monitors" has gone right over the top of my head, I haven`t a clue what you are talking about . If you happen to read this message I wouldn`t mind a reply back with a link showing exactly what you mean just so a novice like me doesn`t get confused .

 

[Mr.Linnet]

Hmmm, I'm not so sure. My Powabyke motor was close to 6 kg. It was a beast of a motor. The brushless motor I replaced it with was around half that. It had no problems getting the bike up steep hills, even though it was low torque. I did improve it by eventually running that one at 48V, which made hill climbing a breeze. Currently it has a Yose Power 250W front motor, (about 35 Nm I think) running at 36 V and it runs fine, even if I don't pedal. With the updates I did to the to the bike, I easily took 10kg off the weight of the bike, which may have helped.

But, so long as it is working fine, he may as well stick with the original motor for now and focus on the battery. If those cracks get worse, or the brushes go, then it will be time to think about the motor update

Many thanks for your latest reply and the comments you make. Have road tested the bike this afternoon and rode it about 6 miles. It went along quite well and it was still showing three bars when I returned home. I did place a meter across the terminals and it read 36.8V so my pedal assist riding certainly helped.

Apart from a few minor tweaks I think I am going to leave well alone. I will look into a replacement lithium battery pack as suggested which I can perhaps also incorporate into my next project of a brushless motor cycle when I find a suitable donor

 

[portals]

"while as just changing the battery for a pair of 8AH 5S lipos with monitors" has gone right over the top of my head, I haven`t a clue what you are talking about

He means you need two batteries both rated at minimum of 8Ah (amp hours - higher number is better for range).

5S means 5 cells in series meaning your battery pack has five cells in series and also some in parallel to to deliver the higher current.

If you know the voltage of the motor eg: 24V/36V etc, you divide that number by 5 to see what voltage the cells should be.

I think

 

[WheezyRider]

It wouldn't make sense anyway to change the motor. You'd have to change the controller and controls too, then why would you want to save a small amount of weight in the motor, when most of the weight is in the battery and massive frame that holds the battery. With that amount of expense, it would make more sense to get a £10 donor from the scrap man and fit a normal ebike kit to it. while as just changing the battery for a pair of 8AH 5S lipos with monitors would be about £100 and would be a massive improvement.

You might ask, "why do this to a 24 year old e-bike?" The bike belonged to my dad originally, so it had some sentimental value to keep it running. Then it kind of became my main bike when I had to have some leg operations which meant I couldn't get my leg over a cross bar on my normal bike. It was a lot of fun to ride, very stable and the fat tyres were good at absorbing the bumps. The big battery enclosure meant that it could be adapted to take almost anything and I experimented with long trips and big batteries - it became a great test bed for stuff. In addition, because of it's age I could have a throttle, which was important after my leg ops which left me hardly able to pedal. The other motivation to reduce its weight was that I sometimes had to get it up steps. The conversion to a modern set up was not expensive, the initial kit was a Voilamart front wheel, which only cost just over £100 back then. They have since increased in price and the latest iteration on the bike is a Yose Power 250W front wheel kit, which cost £170.

The only thing I haven't been able to sort out yet is the bottom bracket. It uses a wider than standard axle which is hard to find. I even asked Powabyke, but they don't have any more old stock.

 

[WheezyRider]

Many thanks for your latest reply and the comments you make. Have road tested the bike this afternoon and rode it about 6 miles. It went along quite well and it was still showing three bars when I returned home. I did place a meter across the terminals and it read 36.8V so my pedal assist riding certainly helped.

Apart from a few minor tweaks I think I am going to leave well alone. I will look into a replacement lithium battery pack as suggested which I can perhaps also incorporate into my next project of a brushless motor cycle when I find a suitable donor

Sounds good. From the voltage after 6 miles, that would be approx 60% full charge remaining. You don't want to go much below 20% (around 35V) but you could probably get another 6 and do 12miles in total on a charge - obviously that will depend on your effort put in, the wind, how hilly, outdoor temperature etc. If 6 miles does the job for you for now, then stick with it until the batteries fade to the point where they don't hold enough charge any longer.

I would not go for Lipo packs, an ordinary e-bike pack will be fine. I usually go for 15Ah or more and you certainly have the space for it on the Powabyke.