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The eBike thread

unkel

A quick look seems that this doesn't really seem to fit in the cycling forum. So starting a thread here about all things eBike

I'll get the ball rolling. I have zero experience with eBikes. But I was going to build myself a battery anyway, for various reasons (like in bringing with me in my EV as a "petrol can")

I'm going to buy a solderless kit to make the battery (with 18650 cells I have removed from dead / old laptop batteries). This kit cah handle 20A max, and I would like the battery pack to produce 1kW constant. P=V*I so 1000W = 50V * 20A

This dictates that my battery needs to be nominal 48V (was thinking of making a 24V battery pack, but that won't be able to charge my car)

A quick browse on eBay and Amazon shows that you could buy a powerful 1000W bike conversion kit with everything needed except the battery for about GBP120 (a bit more from Amazon but peace of mind)

What to buy though, front wheel or rear wheel kit? Pros and cons? Any other advice?

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John Hutton

loughside wrote: »

Hi john, I take it you checked your BB size and all is ok?
Your rear QR `should` be ok, i have that on my HD conversion so far holding up ok, tho saying that i never have to go over PAS4 (out of nine) so try to keep torque in check
You may need this spanner.. see pic.. you`ll find this has to be really tight
The left crank will come loose over time, needs Loctite or similar
If you`re not using the brake levers provided, one of the brake sensors is enough
And before you fit whip off the motor cover, six Allens iirc, and check there`s enough grease on those steel cogs, its common to find little or no grease in there, use AeroShell or similar not the ordinary stuff.
The loom will also be too long, i tidied it into one of those bar bags.
Programming software can be dowmloaded here https://www.poweredride.com/info/bbshd-and-bbs02-configuration-programming-resources
I read in PSW`s ad this `Hot rod programmed for ultimate performance` not something i`d recommend, i`d pull the amps down to 20 for starters, when you`re touring you dont want everything running at peak power.

good luck with the build, you`ll like it!

Yeah the BB is just a regular 68 one.

Speaking of connecting the battery, I think it comes with bullet connectors, should I bother swapping them for Anderson connectors or just slap a load of tape on the bullets to keep water out?

Good call on that tool, I'll buy one.

loughside

John Hutton wrote: »

Speaking of connecting the battery, I think it comes with bullet connectors, should I bother swapping them for Anderson connectors or just slap a load of tape on the bullets to keep water out?

My 02 came with the bullets, never changed them, just make sure they fit tight and you keep the water out.

John Hutton

Ah cool. Looking forward to it all arriving and putting it together, I'll share some pics when I'm done

unkel

I got a cheap 26" wheel with an old ABB 3 phase motor cheaply a while back. Because I still don't have my bike back, I thought I'd give the other components a try. Wired up controller to throttle and to battery. Have voltage at throttle, which apparently is a good sign everything works.

Here's the wheel:

Here's the connector of the wheel:

Brown is neutral / unused? Obviously no hall sensor here.

Connect the 3 phase wires randomly to the white, black and blue (in any combination) and as soon as I press the throttle, there is a distinct but not very loud single click from the motor (I also tried the brown, pretty much the same result)

Here's my video on it:

Linky

You can hear the click from the motor (left audio channel) and then the release click from the throttle much closer by (right audio channel)

Any ideas? Motor broken most likely? Looks like controller, throttle and battery at least are all connected up right?

Joe1919

unkel wrote: »

Motor broken most likely?

Maybe not. Try spinning the motor in the proper direction before flicking the throttle. This gives the controller the opportunity to figure out the motor positions and directions by sensing the voltages (back emf) on the cables before applying power. (I believe in the earlier days of these 3 phase type motors, it was always necessary to pedal the bike initially to get the motor going). This was improved and was not necessary later by using hall sensors or alternatively (sensorless) by fitting some type of learning procedure/learning wires/jumper on controller. As far as I know, this works better on direct drives, as the geared motor freewheel stops motor from turning.
However, I don't have any specific or practical knowledge of this setup.

PS. Dont damage your controller. It would be safer if you could fit some type of overcurrent protection on battery lead e.g. 6amp RCD or fuse. Even a small flick of many throttles will allow full current to motor.
Direct drive motors are relatively easy to test. The motor disconnected should turn with a small lumpy resistance.. Putting a short circuit between the phases (3 combinations, one at a time, with controller disconnected) should make yhe wheel very heavy and stiff to turn. (quick test) If you have a meter, test continuity, colour code etc
I would be a bit worried about that neutral wire i.e. It might need its own controller with 4 wires to be compatible.

[Deleted User]

You have to get the timing right Unkel, hall wires + motor phases, it all has to be in Sync and it can be a pure bitch to get working.

Is it a geared hub ?

[Deleted User]

For testing motor/controller I used to use one of these, I don't know where it went to since I moved House.

unkel

Thanks lads, I'll give that a try.

Deleted User wrote: »

You have to get the timing right Unkel, hall wires + motor phases, it all has to be in Sync and it can be a pure bitch to get working.

Now you're confusing me. Could you please have another look at the pics, only 4 wires coming out of the motor, looks like 3 phase wires and 1 neutral / ground? Seems the motor has no hall wires? What Joe1919 says about the voltages on the phase wires makes some sense. A 3 phase motor is in fact a generator, creating a voltage on the 3 phase wires when spinning even when not connected to anything

Deleted User wrote: »

Is it a geared hub ?

Not 100% sure if it's a direct drive or a geared hub motor

Maybe direct drives don't have hall sensors and geared hub motors do, or is that too much of a generalisation?

I actually bought a very similar tester a few weeks ago for less than a tenner including shipping, it's on its way to me from Chinaland

[Deleted User]

unkel wrote: »

Thanks lads, I'll give that a try.

Now you're confusing me. Could you please have another look at the pics, only 4 wires coming out of the motor, looks like 3 phase wires and 1 neutral / ground? Seems the motor has no hall wires? What Joe1919 says about the voltages on the phase wires makes some sense. A 3 phase motor is in fact a generator, creating a voltage on the 3 phase wires when spinning even when not connected to anything

Not 100% sure if it's a direct drive or a geared hub motor

Maybe direct drives don't have hall sensors and geared hub motors do, or is that too much of a generalisation?

I actually bought a very similar tester a few weeks ago for less than a tenner including shipping, it's on its way to me from Chinaland

Most motors have halls regardless to make starting from a stop easier.

Without halls you need to move the motor to get it to work but this requires a sensorless controller because if a sensored controller is expecting input from the halls and doesn't receive it then it's not going to work.

If a motor has halls and they fail and you don't want to replace them then a sensorless controller is required and it's easy fix the halls just a bit of a bitch to get everything apart and back together especially if it's a geared hub.

The motor in the pics looks like it's a sensorless motor then because there doesn't seem to be hall wires. the 4th wire anyone's guess , perhaps a temp sensor ?

unkel

Deleted User wrote: »

Without halls you need to move the motor to get it to work

Deleted User wrote: »

The motor in the pics looks like it's a sensorless motor then because there doesn't seem to be hall wires.

Yes, that's starting to make sense. This motor does not have hall sensors, so I need to move it

Deleted User wrote: »

Without halls you need to move the motor to get it to work but this requires a sensorless controller because if a sensored controller is expecting input from the halls and doesn't receive it then it's not going to work.

My controller was advertised specifically that it can work with motors both with and without hall sensors, so I hope it will do what it says on the tin!

[Deleted User]

unkel wrote: »

Yes, that's starting to make sense. This motor does not have hall sensors, so I need to move it

My controller was advertised specifically that it can work with motors both with and without hall sensors, so I hope it will do what it says on the tin!

Hopefully it will work.

Geared hubs make a distinctive sound so it should be obvious if it's a geared hub, perhaps while it's off the bike open it up, clear out all the grease and regrrease it. Can only do it good.

Joe1919

Geared motor usually have a freewheel type clutch fitted. This is easily felt by moving the wheel in one direction and then the opposite. The wheel will be free in the normal direction and stiff in the opposite.
The very good booklet from Toshiba pdf below (page 22) give a detailed explanation how sensorless works. It uses a gap (every 60 degrees in the motor timing when the mosfets are off) to sense the motor coil back emf. The motor coils do the job of the hall sensors but not as good.

Sensorless motor control does not use any sensors to detect the rotor position. Instead, the back-EMF voltages from the motor windings can be used for rotor position detection. Back-EMF is the voltage induced in a coil that opposes the change in its magnetic flux that induced it. However, the back-EMF induced in the motor winding of each phase cannot always be detected while a motor is rotating.
Motor terminals cannot be used to measure back-EMF while drive voltages are being applied to them. With 120° commutation, two of the three phases are conducting current at any one time while the other one is not. Back-EMF appears at the terminal of the non-conducting phase, which is measured for rotor position detection. More specifically, the zero-crossing points of back-EMF that appears at each phase terminal are detected.

https://toshiba.semicon-storage.com/info/docget.jsp?did=61176

John Hutton

So, all my stuff arrived and I'm in the process of installing.

Bit of a snag, the battery won't mount on the downtube in the normal orientation as the screw holes are too low down. I can turn it around at mount it the other way around. Is there any issue with mounting the battery the wrong way around?

unkel

Doesn't matter what way you mount the battery.

unkel

Got my fat bike back from Beecycles (SCR)

Linky

Dara, the owner, did a splendid job lacing the hub motor into the fat wheel (with custom order spokes that had to come from Germany) and then fitting the wheel to the bike (with complications like the axle of the hub motor which was too short really for the fork width of the fat bike - so the fork had to be taken out and bent in - and the brake disc system no longer fitted this new setup, so had to be replaced). He also upgraded the shifter and the brake handles (which were both very poor quality, letting the rest of the bike down)

Pleasantly surprised that the whole big fat bike fitted into my humble Hyundai Ioniq, with the boot closed and all

Got the bike home and tested the electric setup. Motor ran, but wheel did not turn (and I had clearly colour matched the 3 phase wires and the 5 hall sensor wires. Messing around the hall sensor wires made no difference but then I remembered that the controller had a "learning wire". Connected that and lo and behold, the wheel was spinning. Disconnected it and it still worked. Hope to hook it all up on the bike and go for a spin over the weekend

[Deleted User]

Cool looking forward to some pics and motor review.

Joe1919

John Hutton wrote: »

Is there any issue with mounting the battery the wrong way around?

Remember the battery is going to be exposed to rain, so I think it would be better mounted the right way up in case there is a small vent on the bottom (or a gap in the gasket) to allow some air to escape (as the battery heats up during use) and its during its cooling stage afterwards , it can draw in moisture.
Some people have used 'rivnuts' (available on ebay) to fit extra eyelets on frame. The battery is heavy and wants to be well mounted.
https://bikepacking.com/gear/rivnut-bottle-cage-mounts/

loughside

John Hutton wrote: »

Is there any issue with mounting the battery the wrong way around?

You mean `upside down`?

Yes!
Rain getting at those contacts.
Rivnuts is the answer if you`ve difficulty lining up those mounting holes.
Or possibly drill a hole in the mounting plate.

John Hutton

loughside wrote: »

You mean `upside down`?

Yes!
Rain getting at those contacts.
Rivnuts is the answer if you`ve difficulty lining up those mounting holes.
Or possibly drill a hole in the mounting plate.

Ok so the battery has a slanted at the front that is supposed to face upwards towards the stem, and a more square end that is supposed to be facing down towards the BB.

It will not fit on in this normal orientation, but if I switch it around so the slanted end is at the BB and the square bit is up at the stem it will fit.

John Hutton

https://sc02.alicdn.com/kf/HTB1CqS5FxGYBuNjy0Fnq6x5lpXam/223340858/HTB1CqS5FxGYBuNjy0Fnq6x5lpXam.jpg

So the opposite way around of how it is mounted on this pic.

loughside

https://en.wikipedia.org/wiki/Dawes_Galaxy#/media/File:1995_Dawes_Galaxy.jpg

If this is your Dawes there should be no problem in fitting a battery in there, that`s a massive frame area compared to some...

Or is it just the bottle holes aren`t lining up for you?
Like has been said drill a couple of holes and fit Rivnuts. I got away with drilling another hole in the holder that i lined up with the second existing bottle cage holder.

John Hutton

loughside wrote: »

https://en.wikipedia.org/wiki/Dawes_Galaxy#/media/File:1995_Dawes_Galaxy.jpg

If this is your Dawes there should be no problem in fitting a battery in there, that`s a massive frame area compared to some...

Or is it just the bottle holes aren`t lining up for you?
Like has been said drill a couple of holes and fit Rivnuts. I got away with drilling another hole in the holder that i lined up with the second existing bottle cage holder.

Bottle holes aren't lining up.

Wouldn't trust myself to drill the frame tbh.

Drilling the mount might be better, would like to avoid drilling at all if possible.

Might mount it the other way around for the time being and buy something that attaches bosses without having to drill holes, like a hinge clamp or something

loughside

I would go for another hole in the mount that lines up..... it shouldn`t be more than hard plastic or aluminium you`re going through, fit a wide washer as well to spread the load.

Suppose an outside possibility if you`re away touring and have those deep saddlebags would be to put it in there out of the way maybe.

John Hutton

Mounted it the way I was referring to, am happy enough with it, have some straps etc on it too.

Took it for a very quick spin. It's powerful! Absolutely powered me up a hill. Speed is limited to 25kph but will increase that a little.

Still waiting for the gear sensor to arrive, So I will fit that then and the programming cable is to arrive as well.

Btw PSWPOWER were excellent, good price and delivered from Germany so no extra taxes etc.

John Hutton

So I took the bike for a approx 30km spin. Some notes:

- Surprised at how little watts were being pulled once I got up to speed. Happily trucked along at 25/30 on the flat with almost no watts being pulled until I either slowed my cadence, even then it only took a little to maintain my speed.
- Hard to gauge battery usage but I'd say I used about 25% at most.
- 25km/hr is too slow. Upped the limit to 40km/hr which was a bit scary fast. It easily achieved that speed. Going to leave it at 35 I think. I'm only using pedal assist with 9 levels. Top speed only reached in level 8 or 9, goes up per assist level, so for instance level five does about 22.
- Found the steepest hill near me, stuck it in assist level 9 and on a big ring at the back and it just zipped up, pulling about 600watts. I was seriously impressed.
- Will take some practice to remember to change gears and assist levels when coming to a stop. Started off from zero at lights with it in assist level 9 and it was actually proper dangerous, nearly ran away with me as I didn't expect it.
- very happy overall, it will be perfect for leisure spins of 60 km or so, maybe more once I get an idea of the range I will get given how I cycle.
- Tried cycling the bike with the assist on zero. Given the extra weight it is more difficult than normal to start from zero, but it is doable and not massively noticable. It felt a bit like when I would previously haul two panniers full of shopping but more steady as the weight is low down. I won't be too worried about having to cycle a little if battery ran out.
- Speed sensor is pretty accurate, was getting roughly the same on my Garmin etrex.
- It was tremendous fun! I did get some exercise, afterwards I felt like I had gone for a decent moderate paced walk, I wasn't really tired at all.

I did pass a Garda car at one stage and had a little anxiety about the legality of the thing. I don't have a throttle so I'm ok there. Where I am running foul is the power of the motor and the speed.

Regarding the speed I think it should be ok as long as I don't draw attention to myself. If I'm doing 35 and visibly pedaling at a decent cadence I say I should be ok as it's plausible that I could be doing that speed under my own power. Any faster and it gets questionable. I'm thinking it is just a case of not taking the piss in town and it should be ok.

Regarding the wattage, I don't see how a Garda could actually tell? In any case I purchased the following sticker off eBay to stick on the bottom.of the motor in the unlikely case a Garda gets nosy.

https://i.ebayimg.com/images/g/HfgAAOSwI2RccsHH/s-l400.jpg

Bigus

Genius on the sticker John , any chance of pictures , of the completed project ?

loughside

Good job John, did you notice how silent it is?
Whats your gearing there, did they send a 44 or 46T ring??

"I did pass a Garda car at one stage" LOL!

I got this metal one off ebay as well..

John Hutton

loughside wrote: »

Good job John, did you notice how silent it is?
Whats your gearing there, did they send a 44 or 46T ring??

"I did pass a Garda car at one stage" LOL!

I got this metal one off ebay as well..

Yes very quiet!! You can only really hear it at low speed when accelerating, even then it is just a low whirr. Once at any speed the road and wind noise cancels it out.

I see yours says 250w at the side as well, very good.

Luckily the Garda was stopped in traffic and I was taking it relatively easy ðŸ˜‚

John Hutton

Bigus wrote: »

Genius on the sticker John , any chance of pictures , of the completed project ?

Sure, I'll take one tonight

John Hutton

loughside wrote: »

Good job John, did you notice how silent it is?
Whats your gearing there, did they send a 44 or 46T ring??

"I did pass a Garda car at one stage" LOL!

I got this metal one off ebay as well..

Sorry it was a 44t