Confused and looking for 48v 250w rear hub since Yose won't sell me 250w 36v kit with 15ah battery

[Peter.Bridge]

Did you experience a 36v system before your 48v Bafang? I know the numbers say 33% more torque & speed (not too worried about the latter) but in real life terms, is the difference that big?

Yes, I also have a 36V rear hub XF08C (which my niece has borrowed for uni !) which I think is brilliant - I can get up slightly steeper hills, slightly faster on the Bafang 48V - I can notice a significant difference but it isn't night and day

I don't think you need brake sensors with a bottom bracket torque sensor - the motor is only on while you are applying pedalling torque - it doesn't operate while ghost pedalling.

 

[saneagle]

Yes, I also have a 36V rear hub XF08C (which my niece has borrowed for uni !) which I think is brilliant - I can get up slightly steeper hills, slightly faster on the Bafang 48V - I can notice the difference but it isn't night and day

I don't think you need brake sensors with a bottom bracket torque sensor - the motor is only on while you are applying pedalling torque - it doesn't operate while ghost pedalling.

Is this right? Your 36v bike has a cadence sensor, so you can easily get max power by pedalling. Your 48v bike has a torque sensor, and the power depends on how hard you pedal.

I have a 36v bike with 15A controller and 48v bike with 14A controller. On max power for hill- climbing, the difference is chalk and cheese. Can we deduce from this that your torque sensor makes it difficult to get full power?

 

[Peter.Bridge]

Is this right? Your 36v bike has a cadence sensor, so you can easily get max power by pedalling. Your 48v bike has a torque sensor, and the power depends on how hard you pedal.

I have a 36v bike with 15A controller and 48v bike with 14A controller. On max power for hill- climbing, the difference is chalk and cheese. Can we deduce from this that your torque sensor makes it difficult to get full power?

No - the 48V bike is slightly less powerful since I fitted the torque sensor kit but that is because the controller is now 15A - the original (48v) kit came with an 18A controller. When I set the LCD to show current with the torque sensor, I get to the maximum current for that PAS level on medium pedalling - so the current varies between light and medium pedalling, but then reaches the maximum assistance at medium pedalling and doesn't increase when I pedal 'harder'

There are hills I can cycle up on the 48V Bafang that I can't on the 36V XF08C . I am thinking about one that is 1.5 miles long , between 10-20% gradient and then has a fifty yard stretch where it increases to 28% - it's that bit where I fail on the XF08C. So I probably cycle up the rest of that hill at 5 mph on the XF08C and 6.5mph on the 48V Bafang. It's a noticeable difference but I think the XF08C has a higher winding which probably narrows the gap (the Bafang is winding code 12). Unrestricted top speed on the flat on a full battery there seems a big difference maybe 26.5 mph vs 19.5 mph

 

[saneagle]

No - the 48V bike is slightly less powerful since I fitted the torque sensor kit but that is because the controller is now 15A - the original (48v) kit came with an 18A controller. When I set the LCD to show current with the torque sensor, I get the to the maximum current for that PAS level on medium pedalling - so the current varies between light and medium pedalling, but then reaches the maximum assistance at medium pedalling and doesn't increase when I pedal 'harder'

There are hills I can cycle up on the 48V Bafang that I can't on the 36V XF08C . I am thinking about one that is 1.5 miles long , between 10-20% gradient and then has a fifty yard stretch where it increases to 28% - it's that bit where I fail on the XF08C. So I probably cycle up the rest of that hill at 5 mph on the XF08C and 6.5mph on the 48V Bafang. It's a noticeable difference but I think the XF08C has a higher winding which probably narrows the gap (the Bafang is winding code 12). Unrestricted top speed on the flat on a full battery there is a big difference maybe 26.5 mph vs 19.5 mph

You're not really making sense. The Woosh 36v XF08C kit has an 18A controller. Is that what you have? In that case You would be misleading that guy, who wants to know the difference between 36v and 48v, because you have an 18A controller with the 36v bike that gives 20% more current than the 48v one, leaving a net power difference of only 10% instead of the actual 30% difference.

 

[Peter.Bridge]

The Woosh 36v XF08C kit has an 18A controller. Is that what you have?

Yep

 

[throwawaychap]

Hi gentlemen, first things first Yose replied to my email.
(I asked, if possible, to be informed of their 350w rear hub motor's RPM at 36v)

They first asked me whether it's a freewheel or cassette and what wheel size.

After I replied: cassette, 700c or 28" they responded:

" Hi,
It's 225±10.
Hope this can help you."

So, on 28" wheels, cassette, the motor is either 215, 225 or 235rpm if I understood it correctly.


On another subject, I'll say I read each post here at least twice, every single one of you have been very helpful.

And, I spent most of the day so far fitting what I can of the kit (since I don't have the battery):

Cassette, got a new rotor with 6 bolts since mine is centre-lock,
new inner tube with a Schrader valve, fitted the PAS sensor.
Now onto the rim tape and tyre.
And then try to determine whether or not I'll need a motor extension cable.

I thankfully did not have to file my dropout/frame. I had measured it 10mm when I first got the bike a few months back. Also, I barely even needed to stretch it to fit the motor wheel.

There's a slight disc rub, but with a little tweak I should be able to smooth it out.

My rotor is 160mm, I was worried I'd need to get a 180mm and an adapter since I saw a recent comment on a Yose conversion video on Youtube about a guy saying his calliper with 160mm rotor rubbed on the motor.

I'm still undecided, spent most of the day mulling over whether to go for the easier 36v route or the slightly more complicated and costly but better 48v system.

Having said that, now knowing that the 350w AKM95RX rear cassette motor, fitted to a 700c by Yose is, as they descrive, 225RPM plus or minus 10.

Hopefully that will help people who come across this thread in the future.

 

[throwawaychap]

Back after a few quick calculations:

Given the RPM Yose gave me at 36v on 700c wheels, these would be the RPM of these motors at 48v (30% increase is my math is correct, rounded up or down).

215 = 279

225 = 292

235 = 305

 

[Woosh]

You should start with your maximum desired speed and work from there.
Motors have a sweet zone where it runs at 80% plus yield and delivers a high enough torque for your needs and stays relatively quiet. If you overvolt it, you move not only the sweet zone to higher speed, you will also reduce the maximum torque and reduce the yield too. It's not a simple equation maximum torque = x * volts , it's a lot more complex than that. Motors shed more heat at lower yield, avoid that first.
If you only want 20-22mph as your maximum speed, don't overvolt your 36v kit.

 

[Peter.Bridge]

So, from the data Yose supplied, depending on tyre size, no load speed of around 25mph (40km/h) at 48v ? Slightly faster on a full battery, slightly slower in an empty battery

 

[saneagle]

Hi gentlemen, first things first Yose replied to my email.
(I asked, if possible, to be informed of their 350w rear hub motor's RPM at 36v)

They first asked me whether it's a freewheel or cassette and what wheel size.

After I replied: cassette, 700c or 28" they responded:

" Hi,
It's 225±10.
Hope this can help you."

So, on 28" wheels, cassette, the motor is either 215, 225 or 235rpm if I understood it correctly.


On another subject, I'll say I read each post here at least twice, every single one of you have been very helpful.

And, I spent most of the day so far fitting what I can of the kit (since I don't have the battery):

Cassette, got a new rotor with 6 bolts since mine is centre-lock,
new inner tube with a Schrader valve, fitted the PAS sensor.
Now onto the rim tape and tyre.
And then try to determine whether or not I'll need a motor extension cable.

I thankfully did not have to file my dropout/frame. I had measured it 10mm when I first got the bike a few months back. Also, I barely even needed to stretch it to fit the motor wheel.

There's a slight disc rub, but with a little tweak I should be able to smooth it out.

My rotor is 160mm, I was worried I'd need to get a 180mm and an adapter since I saw a recent comment on a Yose conversion video on Youtube about a guy saying his calliper with 160mm rotor rubbed on the motor.

I'm still undecided, spent most of the day mulling over whether to go for the easier 36v route or the slightly more complicated and costly but better 48v system.

Having said that, now knowing that the 350w AKM95RX rear cassette motor, fitted to a 700c by Yose is, as they descrive, 225RPM plus or minus 10.

Hopefully that will help people who come across this thread in the future.

Nearly every installation of a rear hub motor results in the disc rubbing. I don't know why they don't fix it. The solution for you is very simple - one standard 12mm washer on the axle on the inside of the drop-out on the left side.

 

[saneagle]

Back after a few quick calculations:

Given the RPM Yose gave me at 36v on 700c wheels, these would be the RPM of these motors at 48v (30% increase is my math is correct, rounded up or down).

215 = 279

225 = 292

235 = 305

That looks about right. 225 rpm in a 700c wheel is 18 mph with a 36v battery and 23.4 mph at 48v. Those maxiimum speeds are with the wheel in the air and the battery half-full. the speed would be about 10% higher when the battery is full and 10% less when empty. The speed on the road will be about 15% lower.

36v battery would be about right if you want to limit the speed to 15 mph. The 48v one would also be fine for that speed. The only significant difference would be the additional 30% torque from 48v.

 

[throwawaychap]

Back with some more news.

I ended up going the easier route with a 36v 20ah battery from Greenlance. Hopefully it serves me well and that means I still have a 48v system in the future to look forward to in a few years' time.

I spent most of the week waiting for parts and fitting what I could of the kit.

I still need a motor cable extension and a battery mount adapter.

I managed to connect all the cables this morning, and turn the system on and it all worked (PAS sensor and throttle), thankfully.

Battery was low.

And curiously, as I fiddled with the settings, Yose's kit came with the controller set to 13A.

It's a 18A controller, I know @Cadence has set his to 17A.

I wonder how high I could set mine, given that I have consistent incline on the way back home. I don't want to run the controller too hot.
I'll probably email Yose to see what they have to say.

But I did find it strange its default position is 13a, I thought it'd be 15a or so.

 

[RollingChunder]

It's a 18A controller, I know @Cadence has set his to 17A.

I wonder how high I could set mine

Assuming your battery is this one: E-Bike Battery Samsung Electric Bike Battery 36V 20AH | Greenlance Limited | Greenlance Limited

Set it all the way up to 18A. It has 20A BMS which you won't exceed.

 

[Cadence]

That's a bit strange. I have 3 Yose 18A max controllers - 2 are separate and 1 is integrated into the battery carrier. They all came preset to 16A. The original 15A max controller that came with the 250w kit was preset to 13A.
I've not had any overheating problems with any of the 18A controllers set to 17A. Motors (350w or250w) and controllers still cool to touch even after some sustained climbing. I don't let the motors run too slow though - keeping speed up on the climb with extra leg-power and going down through the gears to keep up momentum.

 

[throwawaychap]

Assuming your battery is this one: E-Bike Battery Samsung Electric Bike Battery 36V 20AH | Greenlance Limited | Greenlance Limited

Set it all the way up to 18A. It has 20A BMS which you won't exceed.

Yes. That's the one I purchased. 20a BMS, Samsung cells, 2 year warranty.

That's reassuring, I'm tempted. I was thinking of using the kit for a bit stock, and the once I'm sure everything is running fine, tinker with the controller settings a bit.

That's a bit strange. I have 3 Yose 18A max controllers - 2 are separate and 1 is integrated into the battery carrier. They all came preset to 16A. The original 15A max controller that came with the 250w kit was preset to 13A.
I've not had any overheating problems with any of the 18A controllers set to 17A. Motors (350w or250w) and controllers still cool to touch even after some sustained climbing. I don't let the motors run too slow though - keeping speed up on the climb with extra leg-power and going down through the gears to keep up momentum.

I'm also surprised. I will check again tomorrow. I went to display settings, then advanced settings following the supplied booklet/manual, and it read 13. It's a separate controller.

That's valuable information your motors have been running well with controllers set to 17a. Thank you.

 

[throwawaychap]

Another update this morning:

Battery now fully charged.

I lifted the 'speed cap' from 32km/h to 40km/h

With the controller preset to 13A it reached 37km/h. (no load)

With the controller set to 17A it reached 37km/h also. (no load)

I'm still the later reached the speed faster, but I don't know precisely.
I haven't tried setting it to 18A yet, I'd probably only do it to test the no-load speed though.

Edit:

I've now tested it with the controller up to 18A.
Same 37km/h no load speed.

It seems that, despite the settings allowing one to raise the speed cap to 40km/h, it's real limit is 37km/h; which is 22.9mph.

 

[saneagle]

You

Another update this morning:

Battery now fully charged.

I lifted the 'speed cap' from 32km/h to 40km/h

With the controller preset to 13A it reached 37km/h. (no load)

With the controller set to 17A it reached 37km/h also. (no load)

I'm still the later reached the speed faster, but I don't know precisely.
I haven't tried setting it to 18A yet, I'd probably only do it to test the no-load speed though.

Edit:

I've now tested it with the controller up to 18A.
Same 37km/h no load speed.

It seems that, despite the settings allowing one to raise the speed cap to 40km/h, it's real limit is 37km/h; which is 22.9mph.

You only need 1A to reach the no-load maximum speed, so it doesn't make any difference what you set the max current to. The current affects the speed on the road, the acceleration and the hill-climbing speed.

 

[throwawaychap]

You

You only need 1A to reach the no-load maximum speed, so it doesn't make any difference what you set the max current to. The current affects the speed on the road, the acceleration and the hill-climbing speed.

Of all the reading I've done so far, this is the first time I've come across this information, it shows how little I still know hehe.

Thank you Saneagle!

 

[throwawaychap]

Unexpected update:

I received an alarming and unexpected email from Ebay last night:

"Hello X,

We take product safety very seriously. We're reaching out to you because an item you purchased may have been recalled or pose a safety hazard. We recommend that you stop using this product. If you have questions about the item(s), please reach out to the seller or the manufacturer.
Item details are listed below.

More specific details provided below.

We wanted to let you know that an item you ordered is no longer on eBay because of an issue with the seller's account.

It's possible your order shipped before the listing was removed so it bay still arrive, but if you do have any problems you're covered by eBay's Money Back Guarantee and can request a refund.

Order number: X
Item details: X 36v 28"(700c) Black Wheel Rear Motor E-bike Hub Conversion Kit for Cassette

We wanted to let you know that an item you ordered is no longer on eBay because of an issue with the seller's account.

If you have any questions, please go to 'Help & Contact' at the top of most eBay pages.

eBay

Please don't reply to this message. It was sent from an address that doesn't accept incoming email."

----------------------------------------------------------------------------------------

Obviously my kit has arrived.

It all looked brand new, and I was impressed by the components quality wise, granted I'm someone who's never dealt with e-bike kits before.

I have bought the kit without the battery. So I don't understand what could be construed as hazardous in the kit.

Since I received my Greenlance battery, I've connected everything and the system worked fine as far as briefly testing no-load speed goes.

There are two Yose Power stores on Ebay:

qx-official-eshopuk / Battery of YS-2020

Security measure

www.ebay.co.uk

(above is the store I ordered my kit from)


ysbatteryuk

Security measure

www.ebay.co.uk

(their other store)

----------------------------------------------------------------------------------

Now, do I ask for a refund since eBay is adamant I do not use the kit?
Will I have to return it?

I have not quite processed the issue fully yet.

My bike is still not finished. I still need a battery mount adapter to complete the job.

Edit: (extra info)
The kit I bought had been sold hundreds of times, and there were only a few left.
It differs from other Yose Power kits because it came with a battery cable adapter (julet to bullet connectors) that you otherwise have to order separately.

 

[Peter.Bridge]

Unexpected update:

I received an alarming and unexpected email from Ebay last night:

"Hello X,

We take product safety very seriously. We're reaching out to you because an item you purchased may have been recalled or pose a safety hazard. We recommend that you stop using this product. If you have questions about the item(s), please reach out to the seller or the manufacturer.
Item details are listed below.

More specific details provided below.

We wanted to let you know that an item you ordered is no longer on eBay because of an issue with the seller's account.

It's possible your order shipped before the listing was removed so it bay still arrive, but if you do have any problems you're covered by eBay's Money Back Guarantee and can request a refund.

Order number: X
Item details: X 36v 28"(700c) Black Wheel Rear Motor E-bike Hub Conversion Kit for Cassette

We wanted to let you know that an item you ordered is no longer on eBay because of an issue with the seller's account.

If you have any questions, please go to 'Help & Contact' at the top of most eBay pages.

eBay

Please don't reply to this message. It was sent from an address that doesn't accept incoming email."

----------------------------------------------------------------------------------------

Obviously my kit has arrived.

It all looked brand new, and I was impressed by the components quality wise, granted I'm someone who's never dealt with e-bike kits before.

I have bought the kit without the battery. So I don't understand what could be construed as hazardous in the kit.

Since I received my Greenlance battery, I've connected everything and the system worked fine as far as briefly testing no-load speed goes.

There are two Yose Power stores on Ebay:

qx-official-eshopuk / Battery of YS-2020

Security measure

www.ebay.co.uk

(above is the store I ordered my kit from)


ysbatteryuk

Security measure

www.ebay.co.uk

(their other store)

----------------------------------------------------------------------------------

Now, do I ask for a refund since eBay is adamant I do not use the kit?
Will I have to return it?

I have not quite processed the issue fully yet.

My bike is still not finished. I still need a battery mount adapter to complete the job.

Was it the 350w kit ? I think Amazon and eBay (I read somewhere on these forums) have a policy of not selling non compliant e bikes / kits, but I suspect this is policed after the sale. I suspect that is the reason for the email, but if you don't return the kit eBay are not liable - but that is conjecture on my part.

Contact Yosepower direct ?

service@yosepower.co.uk