It will always get more power from the controller on the highest level, so don't waste your time trying the lower levels. The only difference between the levels is the speed at which the power starts ramping down, which is lower for the lower levels. Your best solution would be to run a blob of solder up one leg of the shunt, with the aim to cover about 25% of the length of the whole shunt and no more. That will give you 25% more torque.

 

Doing things on the cheap gives you a cheap solution. You should never buy a controller unless it tells you its max current. Now, the only way to find out is with an £8 wattmeter from Ebay.

It will always get more power from the controller on the highest level, so don't waste your time trying the lower levels. The only difference between the levels is the speed at which the power starts ramping down, which is lower for the lower levels. Your best solution would be to run a blob of solder up one leg of the shunt, with the aim to cover about 25% of the length of the whole shunt and no more. That will give you 25% more torque.

 

Doing things on the cheap gives you a cheap solution. You should never buy a controller unless it tells you its max current. Now, the only way to find out is with an £8 wattmeter from Ebay.

Are you saying that the reported wattage on the display isn't accurate?

I wondered if the fact that this is a 24v motor with a 36v battery would make the *no load" speed 50% higher, so at low speeds it would take this motor out of its efficient operating zone. I wondered as you approached the level 1 and 2 limit speeds, does a speed controller reduce the voltage or reduce the current ? If it reduced the voltage the "no load" speed would reduce and the motor speed might fall into the efficient zone and provide more power. I suspect from what [mention=3847]saneagle[/mention] says that it is the current that reduces, that wouldn't help.

The display and any wattmeter you might add can only measure the power taken from the battery, not the power delivered by the motor. At low speeds the efficiency of a hub motor drops off badly, so delivered power can be much lower than that displayed.

 

Going back to the hill, are you able to maintain constant speed up it, and is the gradient even, or does speed drop off as you go up, or is gradient steeper at the top? The motor casing remains cool: what about the controller?

I'll do some more testing if it ever stops raining.

The display and any wattmeter you might add can only measure the power taken from the battery, not the power delivered by the motor. At low speeds the efficiency of a hub motor drops off badly, so delivered power can be much lower than that displayed.

 

Going back to the hill, are you able to maintain constant speed up it, and is the gradient even, or does speed drop off as you go up, or is gradient steeper at the top? The motor casing remains cool: what about the controller?

 

 

The controller is screwed to a flat metal plate that is welded to the frame, so I doubt that it's getting hot, but hard to check without taking the covers off.

I could attach a temperature sensor, but there are already too many cables and connectors vying for space.

Are you saying that the reported wattage on the display isn't accurate?

It's not definitive, neither does it say whether it's a maximum or rating. Most controllers are definitive. They say something like "Max Current 15A, Rated Current 7A".

 

Is there a specification in the listing from where you bought it?

It's not definitive, neither does it say whether it's a maximum or rating. Most controllers are definitive. They say something like "Max Current 15A, Rated Current 7A".

 

Is there a specification in the listing from where you bought it?

https://amzn.eu/d/io12pGf

https://amzn.eu/d/io12pGf

This looks like the same one. It has 13A max current written on the label. Does yours have that?

https://www.amazon.co.uk/dp/B07WYMMQTD/ref=sspa_dk_detail_1?psc=1&pd_rd_i=B07WYMMQTD&pd_rd_w=eDPYE&content-id=amzn1.sym.46187d6a-4306-4bc6-830c-7b2085e0e39f&pf_rd_p=46187d6a-4306-4bc6-830c-7b2085e0e39f&pf_rd_r=S016X68A3CTYVAHBQ77D&pd_rd_wg=rymTN&pd_rd_r=b0e496ea-b452-4ec7-8ac8-e4787b924c81&s=sports&sp_csd=d2lkZ2V0TmFtZT1zcF9kZXRhaWw

 

If yours is 13A, that's the reason for the lack of power. Soldering 25% of the shunt will get it up to a more useful 16.5A.

This looks like the same one. It has 13A max current written on the label. Does yours have that?

https://www.amazon.co.uk/dp/B07WYMMQTD/ref=sspa_dk_detail_1?psc=1&pd_rd_i=B07WYMMQTD&pd_rd_w=eDPYE&content-id=amzn1.sym.46187d6a-4306-4bc6-830c-7b2085e0e39f&pf_rd_p=46187d6a-4306-4bc6-830c-7b2085e0e39f&pf_rd_r=S016X68A3CTYVAHBQ77D&pd_rd_wg=rymTN&pd_rd_r=b0e496ea-b452-4ec7-8ac8-e4787b924c81&s=sports&sp_csd=d2lkZ2V0TmFtZT1zcF9kZXRhaWw

 

If yours is 13A, that's the reason for the lack of power. Soldering 25% of the shunt will get it up to a more useful 16.5A.

 

On the Amazon listing the OP linked to the sticker on it said current 11a limiting 13a

On the Amazon listing the OP linked to the sticker on it said current 11a limiting 13a

On the Amazon listing the OP linked to the sticker on it said current 11a limiting 13a

Maybe you're viewing it on a computer, I can't read that on my phone.

Maybe you're viewing it on a computer, I can't read that on my phone.

Took a screenshot and used the Google photo editing wizardry, it's very faint on the listing :-)

 

Edited December 1, 20241 yr by Peter.Bridge

This looks like the same one. It has 13A max current written on the label. Does yours have that?

https://www.amazon.co.uk/dp/B07WYMMQTD/ref=sspa_dk_detail_1?psc=1&pd_rd_i=B07WYMMQTD&pd_rd_w=eDPYE&content-id=amzn1.sym.46187d6a-4306-4bc6-830c-7b2085e0e39f&pf_rd_p=46187d6a-4306-4bc6-830c-7b2085e0e39f&pf_rd_r=S016X68A3CTYVAHBQ77D&pd_rd_wg=rymTN&pd_rd_r=b0e496ea-b452-4ec7-8ac8-e4787b924c81&s=sports&sp_csd=d2lkZ2V0TmFtZT1zcF9kZXRhaWw

 

If yours is 13A, that's the reason for the lack of power. Soldering 25% of the shunt will get it up to a more useful 16.5A.

It's not like a lack of power, it feels more like it just cuts out. At the top of the hill everything's fine again...

It's not like a lack of power, it feels more like it just cuts out. At the top of the hill everything's fine again...

It doesn't seem like a long/steep/high enough hill to trigger low voltage cutoff or thermal cutoff, no brake switches to go wrong, cadence sensor working fine, I can't see an answer from afar!

How fast is the bike moving at cut out.

It doesn't seem like a long/steep/high enough hill to trigger low voltage cutoff or thermal cutoff, no brake switches to go wrong, cadence sensor working fine, I can't see an answer from afar!

I know, weird? It's probably just user error. I'll get out there again, stay in low gear and make sure I pedal constantly to the top. The problem is that cars keep driving up and down and I don't have the confidence I had 5 or 10 years ago. And the potholes...

How fast is the bike moving at cut out.

Once again, I don't really know, there's too much going on at once.

Alternatively, I could jury rig a throttle, just for experimental purposes, but that's not my aim.

I would also be interested in the "no load" speed (with the motor wheel lifted off the ground). I suspect this might be too high for strong hill climbing although the controller shunt mod will definitely help

I would also be interested in the "no load" speed (with the motor wheel lifted off the ground). I suspect this might be too high for strong hill climbing although the controller shunt mod will definitely help

Hard to say, without moving the spoke magnet sensor to the front(driven) wheel.

Did you try the bike using a lower assist level on that hill ?

Only just got back to this - had to clad our new oak framed garage, supervise the slate roof and all manner of other things. Played around in our paddock today, and I now totally understand what you've all been saying about speed based rather than power based. It doesn't really feel like pedal assist, it feels like pedal a revolution or something, motor tries to achieve a fixed speed, stop pedalling and after a (too long for my liking) delay, motor cuts out. All the ebikes I've ridden before feel more like I have bionic legs, which is what I'm after. So I guess I'm going to throw some more cash at the problem and buy a KT controller and compatible display.

Found this on eBay, any thoughts?

https://ebay.us/m/vTa66t

I think 30a would be too much, 20a here

 

https://www.pswpower.com/products/kt-kunteng-electric-bicycle-motor-ebike-controller-24v-36v-48v-250w-500w-1000w-brushless-dc-sine-wave-sensor-controller-331

Only just got back to this - had to clad our new oak framed garage, supervise the slate roof and all manner of other things. Played around in our paddock today, and I now totally understand what you've all been saying about speed based rather than power based. It doesn't really feel like pedal assist, it feels like pedal a revolution or something, motor tries to achieve a fixed speed, stop pedalling and after a (too long for my liking) delay, motor cuts out. All the ebikes I've ridden before feel more like I have bionic legs, which is what I'm after. So I guess I'm going to throw some more cash at the problem and buy a KT controller and compatible display.

Found this on eBay, any thoughts?

https://ebay.us/m/vTa66t

Can you remind us which battery and motor you have? Are you currently running with 36v or still on 24v?

Giant sync drive front hub motor, 36v 10.5ah battery from Yosepower..