Dengfu E22 Frame Thread

[bram.biesiekierski]

Yes you are correct in your senario the torque at the rear wheel would be the same but your missing my point and proving my point at the same time in essence you saying exactly what I'm telling you. All I'm saying is felt force or torque i guess on the cassette is measured by the rsstance required to stop the force and the fat guy requires more for the same result thus putting more tension on the cassette . doesnt matter who accelerates faster in your scenario yes both riders are putting equal force on there chains but the lighter guy is faster his doesn't matter the fat guy is still trying to achieve the same result and will need more force to get there ..

No. You are still wrong my friend. In my example with the 2 riders. The torque in each bike is IDENTICAL.

THE MOTOR IS THE SAME.

THE MOTOR PRODUCES THE SAME TORQUE AT FULL THROTTLE / PEDDLE ASSIST.

THE TORQUE IN THE CHAIN RING IS THE SAME.

THE TENSION IN THE CHAIN IS THE SAME.

THE TORQUE INTO THE CASSETTE IS ALSO, YOU GUESSED IT. THE FUCKING SAME.

 

[bram.biesiekierski]

Felt force is nonsensical. There is torque. There is tension. There is compression. There is shear.

But there is no such thing as felt force. It doesn't exist

 

[CaptainBobt]

I think you are going about it back to front in your head. The motor is the source of the torque/power. This is where you must start in trying to understand whats happening. It seams you are thinking about this in back to front logic. You are thinking about it from the rear wheel forwards. Not from the motor back.

When you request power by either pushing the throttle, or request power via peddalling with peddle assist switched on. The motor begins generating torque. The motor doesn't know what gear ratio your in etc. It just starts putting force into rotating its output shaft (the chainring.)

This rotational force goes through the drivetrain, through a gear reduction or multiplication depending on what gear ratio you have selected. And then into the rear wheel, and ultimately begins accelerating you and the bike.

The motor generates torque dependent on how much you press the throttle, or what level pedal assist you have selected. You seem to be confused at this part. You seam to think the motor only generates as much torque as it takes to rotate the wheel, and no more. Where infact the motor generates only as much torque as you request (either via throttle or peddal assist level).

This motor torque ultimately starts rotaing the rear wheel. If the gear ratio selected is very high, or the rider is very heavy, or there's a steep hill, (what you call resistence) the amount the rear wheel accelerates is will be less. If the gear ratio is very pow, or the rider is light, or your going down hill, it won't change how much torque the motor makes. It's only going to change how much acceleration results from that torque.

I hope I explained that in a way you can wrap your head around

Okay listen, please, Torque is measured and purely measured alone by the force required to stop that force .. acceleration has nothing to do with it. That is a result . it doesn't matter what you apply it to if you are trying to achieve a certain result in your case faster acceleration to a given speed a bike with more resistance will have or need to have higher torque to reach that outcome than a bike with less.. thus putting much more strain on the components. If you chose to use a small gog up a hill your are essentially creating resistance by asking to go fast wich will determine how much torque will be applied .

 

[CaptainBobt]

Okay listen, please, Torque is measured and purely measured alone by the force required to stop that force .. acceleration has nothing to do with it. That is a result . it doesn't matter what you apply it to if you are trying to achieve a certain result in your case faster acceleration to a given speed a bike with more resistance will have or need to have higher torque to reach that outcome than a bike with less.. thus putting much more strain on the components. If you chose to use a small gog up a hill your are essentially creating resistance by asking to go fast wich will determine how much torque will be applied .

Okay listen, please, Torque is measured and purely measured alone by the force required to stop that force .. acceleration has nothing to do with it. That is a result . it doesn't matter what you apply it to if you are trying to achieve a certain result in your case faster acceleration to a given speed a bike with more resistance will have or need to have higher torque to reach that outcome than a bike with less.. thus putting much more strain on the components. If you chose to use a small gog up a hill your are essentially creating resistance by asking to go fast wich will determine how much torque will be applied .

No. You are still wrong my friend. In my example with the 2 riders. The torque in each bike is IDENTICAL.

THE MOTOR IS THE SAME.

THE MOTOR PRODUCES THE SAME TORQUE AT FULL THROTTLE / PEDDLE ASSIST.

THE TORQUE IN THE CHAIN RING IS THE SAME.

THE TENSION IN THE CHAIN IS THE SAME.

THE TORQUE INTO THE CASSETTE IS ALSO, YOU GUESSED IT. THE FUCKING SAME.

If you think anytime you give your bike full throttle you applying 160nm of torque to your cassette no matter what gear what speed what weight hell how much wind even, your delusional..

 

[bram.biesiekierski]

Okay listen, please, Torque is measured and purely measured alone by the force required to stop that force .. acceleration has nothing to do with it. That is a result . it doesn't matter what you apply it to if you are trying to achieve a certain result in your case faster acceleration to a given speed a bike with more resistance will have or need to have higher torque to reach that outcome than a bike with less.. thus putting much more strain on the components. If you chose to use a small gog up a hill your are essentially creating resistance by asking to go fast wich will determine how much torque will be applied .

Acceleration has everything to do with it. F=MA it is fundamental to this whole debate.

We know the motors are identical. We know they produce the same torque. We know the drivetrains and tyres are the same. And they are in the same gear.

There is no such thing as "FELT FORCE". It doesn't exist. It's nonsensical. There is no such thing. There is no calculations for felt force. It doesn't not appear in any physics formulas. It simply is not a thing.

The only variable I'm the above examples is acceleration. That is the only thing that changes.

 

[bram.biesiekierski]

Th

Okay listen, please, Torque is measured and purely measured alone by the force required to stop that force .. acceleration has nothing to do with it. That is a result . it doesn't matter what you apply it to if you are trying to achieve a certain result in your case faster acceleration to a given speed a bike with more resistance will have or need to have higher torque to reach that outcome than a bike with less.. thus putting much more strain on the components. If you chose to use a small gog up a hill your are essentially creating resistance by asking to go fast wich will determine how much torque will be applied .

The motors ARE THE SAME. The heavy riders bike has the same motor as the light rider. It has the same torque. The same power. The same everything.

One can not simply make more torque than the other, simply because there is a lighter or heavier rider on it. It is physically impossible.

 

[bram.biesiekierski]

I remember back to a quote.

"Never get into an argument with stupid, it will drag you down to its level, and then beat you with experience."

 

[bram.biesiekierski]

Let's say I have a 500hp car. If I take the seats amd spare tyre out, the car will be lighter. The engine will not be any more or less powerfull.

 

[CaptainBobt]

Acceleration has everything to do with it. F=MA it is fundamental to this whole debate.

We know the motors are identical. We know they produce the same torque. We know the drivetrains and tyres are the same. And they are in the same gear.

There is no such thing as "FELT FORCE". It doesn't exist. It's nonsensical. There is no such thing. There is no calculations for felt force. It doesn't not appear in any physics formulas. It simply is not a thing.

The only variable I'm the above examples is acceleration. That is the only thing that

Th

The motors ARE THE SAME. The heavy riders bike has the same motor as the light rider. It has the same torque. The same power. The same everything.

One can not simply make more torque than the other, simply because there is a lighter or heavier rider on it. It is physically impossible.

Torque isn't made it is measured on how much rotational force the power of a motor can apply. and again it is a direct measurement of how much resistance that power can overcome. sorry that doesn't make sense to you . Do you own a torque wrench..? That's why I used felt force to try and explain why torque of a motor has no ability to break things unless it faces resistance . But I don't think that's going to sink in either .

 

[bram.biesiekierski]

Torque isn't made it is measured on how much rotational force the power of a motor can apply. and again it is a direct measurement of how much resistance that power can overcome. sorry that doesn't make sense to you . Do you own a torque wrench..? That's why I used felt force to try and explain why torque of a motor has no ability to break things unless it faces resistance . But I don't think that's going to sink in either .

The "rotational force a motor can apply" is torque. That is the literal definition.

The "power" of a motor is dependant on its torque, and the RPM at which it generates that torque.

Torque is a physical thing. Not just something that "can be measured".

Your grasp on physics is borderline illiterate. I'm not sure I can explain this any simpler than I am.

Yes I own 5 torque wrenchs. I have 3 electronic ones, and 2 deflecting beam wrenchs. In half inch square all the way down to 1/4" hex. I am very well versed in what torque is and how it is measured.

Lastly. There is always going to be "RESISTANCE". (Unless you know how to magically make your body and bike mass-less.) Because our bikes and bodies have mass, it means there must be resistance. Accelerating the mass is the resistance. Any difference in mass, is only going to change the resulting acceleration. The resistence is always going to be equal. It will not and can not change force, felt or otherwise.


And just incase you missed it. "Felt force" does not exist. It is nonsensical. There is no such thing. There are no physics formulas to calculate felt force. It doesn't appear in any physics textbooks.

 

[BootsDave]

Hey guys. The straight forward answer to avoid breaking your chain/cassette is use a lower gear. Even with my M500, I managed to break a chain being in too high a gear on a steep climb, and I’m only 67kg.

 

[CaptainBobt]

Hey guys. The straight forward answer to avoid breaking your chain/cassette is use a lower gear. Even with my M500, I managed to break a chain being in too high a gear on a steep climb, and I’m only 67kg.

The "rotational force a motor can apply" is torque. That is the literal definition.

The "power" of a motor is dependant on its torque, and the RPM at which it generates that torque.

Torque is a physical thing. Not just something that "can be measured".

Your grasp on physics is borderline illiterate. I'm not sure I can explain this any simpler than I am.

Yes I own 5 torque wrenchs. I have 3 electronic ones, and 2 deflecting beam wrenchs. In half inch square all the way down to 1/4" hex. I am very well versed in what torque is and how it is measured.

Lastly. There is always going to be "RESISTANCE". (Unless you know how to magically make your body and bike mass-less.) Because our bikes and bodies have mass, it means there must be resistance. Accelerating the mass is the resistance. Any difference in mass, is only going to change the resulting acceleration. The resistence is always going to be equal. It will not and can not change force, felt or otherwise.

Hey guys. The straight forward answer to avoid breaking your chain/cassette is use a lower gear. Even with my M500, I managed to break a chain being in too high a gear on a steep climb, and I’m only 67kg.

Thank y
And just incase you missed it. "Felt force" does not exist. It is nonsensical. There is no such thing. There are no physics formulas to calculate felt force. It doesn't appear in any physics textbooks.
Felt force is something is certainly something I dont remeber ever saying it wasa term in physics.. say I punch you in the Face with 400 nm and your backing up as I do will you feel that force less..? Say I punch you in the face while you ri ning towards meAll I kow is if you think every time on't remember did I e

Hey guys. The straight forward answer to avoid breaking your chain/cassette is use a lower gear. Even with my M500, I managed to break a chain being in too high a gear on a steep climb, and I’m only 67kg.

Thank you,

 

[CaptainBobt]

The "rotational force a motor can apply" is torque. That is the literal definition.

The "power" of a motor is dependant on its torque, and the RPM at which it generates that torque.

Torque is a physical thing. Not just something that "can be measured".

Your grasp on physics is borderline illiterate. I'm not sure I can explain this any simpler than I am.

Yes I own 5 torque wrenchs. I have 3 electronic ones, and 2 deflecting beam wrenchs. In half inch square all the way down to 1/4" hex. I am very well versed in what torque is and how it is measured.

Lastly. There is always going to be "RESISTANCE". (Unless you know how to magically make your body and bike mass-less.) Because our bikes and bodies have mass, it means there must be resistance. Accelerating the mass is the resistance. Any difference in mass, is only going to change the resulting acceleration. The resistence is always going to be equal. It will not and can not change force, felt or otherwise.


And just incase you missed it. "Felt force" does not exist. It is nonsensical. There is no such thing. There are no physics formulas to calculate felt force. It doesn't appear in any physics textbooks.

What are you talking a out now If you think we run around all day putting 160nm of torque

 

[CaptainBobt]

The "rotational force a motor can apply" is torque. That is the literal definition.

The "power" of a motor is dependant on its torque, and the RPM at which it generates that torque.

Torque is a physical thing. Not just something that "can be measured".

Your grasp on physics is borderline illiterate. I'm not sure I can explain this any simpler than I am.

Yes I own 5 torque wrenchs. I have 3 electronic ones, and 2 deflecting beam wrenchs. In half inch square all the way down to 1/4" hex. I am very well versed in what torque is and how it is measured.

Lastly. There is always going to be "RESISTANCE". (Unless you know how to magically make your body and bike mass-less.) Because our bikes and bodies have mass, it means there must be resistance. Accelerating the mass is the resistance. Any difference in mass, is only going to change the resulting acceleration. The resistence is always going to be equal. It will not and can not change force, felt or otherwise.


And just incase you missed it. "Felt force" does not exist. It is nonsensical. There is no such thing. There are no physics formulas to calculate felt force. It doesn't appear in any physics textbooks.

I never said felt force was a physics term sorry you took that personally. IMO you have missed my whole point because you wrapped up in how much torque our motors have. What your missing is where that torque can break stuff and why. Fr
Or maybe the person on here who doest have reflector beam wrenches. I'm sorry but you certain can change the amount of torque and stress you putting on the parts on your bike just by losing weight and proper gears election if you don't thi k that then your delusional.

 

[Neeko DeVinchi]

Anywho, changing the subject slightly

This is what my suspension chap has provided me via WhatsApp after having my E22 for a week and a bit.

Please note, Dengfu have not provided me this. Rather this leverage curve rate has been provided by a third party suspension experts.

I have sent an email to Dengfu, for them to comment on the above. I'll keep you posted on their response.
Nevertheless, my suspension chap remains confident that this will aid others in dialing in the suspension (air or coil)

 

[bram.biesiekierski]

What are you talking a out now If you think we run around all day putting 160nm of torque

I do. When i want to ride fast and feel adrenilin. I keep it in level 5 sport, and use the throttle liberally.

 

[bram.biesiekierski]

Anywho, changing the subject slightly
View attachment 92597

This is what my suspension chap has provided me via WhatsApp after having my E22 for a week and a bit.

Please note, Dengfu have not provided me this. Rather this leverage curve rate has been provided by a third party suspension experts.

I have sent an email to Dengfu, for them to comment on the above. I'll keep you posted on their response.
Nevertheless, my suspension chap remains confident that this will aid others in dialing in the suspension (air or coil)

Nice. I was wondering how that was going.

Looks nice and progressive. Leveridge ratio starting up over 3:1 and finishing under 2.5:1.

Did your suspension guys comment on on any of the other characteristics of the design, such as anti-rise/sqaut, peddle kick, peddle bob, or axle path?

 

[bram.biesiekierski]

What are you talking a out now If you think we run around all day putting 160nm of torque

Once again. You have completely missed the point.

It doesn't matter if you use full throttle or full pedal assist only 5% of the time, or 50% of the time. The drivetrain needs to be able to transmit that power to the wheel.

Here another basic analogy for you. Let's say you have a 500hp car, and every time you drive that car, and use wide open throttle, the clutch slips.

Doesn't matter if you use it once per month to overtake a slow moving truck, or everytime you drive it. It's a problem right???

You have 2 choices.

A - Leave it alone, and simply never use wide open throttle again.

Or

B - Remove and replace the clutch with something more heavy duty. Perhaps a clutch with higher clamp force. Or higher coefficient friction material. Or perhaps a multiple plate clutch.

I know what I would do. I would fix the problem. Because I enjoy the feeling I get when I use full throttle. It seams some people on here throw thier hands up in the air, and say, well I must be driving it wrong. Or it's all too hard, I'm just not gonna use full throttle. Or maybe I will take the car down to the tune shop, and asked them to make my 500hp car into a 400hp car. The logic is all backwards.

 

[Waynemarlow]

I do. When i want to ride fast and feel adrenilin. I keep it in level 5 sport, and use the throttle liberally.

And only very momentarily will you use the full 160Nm of torque available and that will be for incrediably short periods of time. The chances of using full power constantly and converting that into a steady speed is almost never going to happen.

By any chance do you have the torque curve of the engine, if you do you will see that the 160Nm will not be at 0 revs, there's far too much risk of overheating the engine for any manufacturer to allow full power in lower rpm situations and will prevent it electronically. Equally the manufacturer will almost certainly be using field weakening to get a flatter torque curve, so the 160Nm will be at mid revs which almost certainly will be whilst on the move ( again electronically controlled ) which almost certainly will mean whilst under accelaration or change of speed for tiny periods of time.

Theres so many variables here on power being absorbed by the drivetrain and where its failure point will be, that it would cost many millions in FEA analysis to prove. No manufacturer is going to do that, its far cheaper to use known failure of components in the millions of miles from 100 years + of use.

Sorry guys Nm's is almost meaningless unless we know the full story. However Watts of energy being used, now thats a whole lot more useful. Put a logger on your battery and you may well get the answer you want to know.

 

[bexamous]

160nm doesn't seem like that much... 205lbs person with cranks level if they stand on one foot that's 160nm torque. I'm like 215lbs and not afraid of that breaking a chain.

Heh googling, not sure if this is true:

> The German Industrial Standard sets minimum breaking loads for standard bicycle chains at 8,200 Newton and at 10,000 Newton for derailleur bicycle chains. The industry follows these standards pretty well.

And another site:

> Wippermann's internal standard is 9,500-11,000 Newtons of breaking force for its bicycle chains,

So 100kg person standing on pedals with the stock chainring, holding up ruler it seems roughly 87mm radius, that would be:

>>> 100*9.8*0.175/0.087
1971.264367816092

2000N on a chain rated for least 8000N? Doubling that for motor's 160nm torque still half what it should be rated for.

But not sure where this 160nm rating comes from really.. like 1000watts is 160nm toque with 60rpm cadence.. but like when struggling in climb at 30rpm cadence and bafang display says motor is doing 1000watts... how is not doing >160nm of torque? And like controller doesn't monitor phase current.. how would it limit torque? Maybe why stock controller sets Spd0's max current to 20%? As way to limit torque/heat at lower rpm? I'd guess if you raised up Spd0's max current you'd be more likely to break chains. But I dont' really have an experience with the stock controller.

FWIW I generally just try to be in a reasonable gear.. I actually find bike rides better with I target a higher cadence.. especially with shorter 160mm crank arms. Main thing through is when I do end up in the wrong gear, I don't rely on motor to power through. I'll jump off and redo whatever. Oh and when I had throttle hooked up I just avoided slaming on throttle when at a dead stop. First chain I think i got 800-1000 miles.. which seems pretty reasonable.

 

[bram.biesiekierski]

And only very momentarily will you use the full 160Nm of torque available and that will be for incrediably short periods of time. The chances of using full power constantly and converting that into a steady speed is almost never going to happen.

By any chance do you have the torque curve of the engine, if you do you will see that the 160Nm will not be at 0 revs, there's far too much risk of overheating the engine for any manufacturer to allow full power in lower rpm situations and will prevent it electronically. Equally the manufacturer will almost certainly be using field weakening to get a flatter torque curve, so the 160Nm will be at mid revs which almost certainly will be whilst on the move ( again electronically controlled ) which almost certainly will mean whilst under accelaration or change of speed for tiny periods of time.

Theres so many variables here on power being absorbed by the drivetrain and where its failure point will be, that it would cost many millions in FEA analysis to prove. No manufacturer is going to do that, its far cheaper to use known failure of components in the millions of miles from 100 years + of use.

Sorry guys Nm's is almost meaningless unless we know the full story. However Watts of energy being used, now thats a whole lot more useful. Put a logger on your battery and you may well get the answer you want to know.

Yes. I have seen some torque curves for the bafang ultra, with stock 750w controller, stock 1000w controller and Archon X1 controller at various power levels.

Interestingly, the graph X axis is showing MPH though, and there is no mention of gear ratio, or wheel size. I would have expected it to show RPMs??? I'm suspect perhaps the measurements are taken at the wheel, as opposed to at the output shaft of the motor.

The 1000w bafang ultra torque output oscillates between 80nm and 140nm early on. But is overall very flat/linear all the way up to 30mph. I would expect it to be very linear once you apply some basic smoothing to the graph. (This is very standard with dyno graphs.) It looks like the plots for the Archon X1 have had smoothing applied.

I presume the reason the graph is measuring 140nm, and the motor manufactures claim output of 160nm is possibly due to the way it was measured. Given that the graph shows MPH and not RPM, I think we can assume it's a wheel measurement as setup and mounted to a bike, as opposed to a measurement taken directly at the motor output. Or it could even be a theoretical/calculated graph, based off logged electrical outputs from the controller into the motor.

There is as you say, very little torque at 0mph, but it quickly ramps up to its peak before 5mph. And apart from the oscillations, it remains relatively flat and linear all the way up to 30mph. Although this is kind of useless I fo without knowing the motor RPMs, or the ratio and wheel size.

 

[bram.biesiekierski]

And only very momentarily will you use the full 160Nm of torque available and that will be for incrediably short periods of time. The chances of using full power constantly and converting that into a steady speed is almost never going to happen.

By any chance do you have the torque curve of the engine, if you do you will see that the 160Nm will not be at 0 revs, there's far too much risk of overheating the engine for any manufacturer to allow full power in lower rpm situations and will prevent it electronically. Equally the manufacturer will almost certainly be using field weakening to get a flatter torque curve, so the 160Nm will be at mid revs which almost certainly will be whilst on the move ( again electronically controlled ) which almost certainly will mean whilst under accelaration or change of speed for tiny periods of time.

Theres so many variables here on power being absorbed by the drivetrain and where its failure point will be, that it would cost many millions in FEA analysis to prove. No manufacturer is going to do that, its far cheaper to use known failure of components in the millions of miles from 100 years + of use.

Sorry guys Nm's is almost meaningless unless we know the full story. However Watts of energy being used, now thats a whole lot more useful. Put a logger on your battery and you may well get the answer you want to know.

I also agree with you that absolute NMs are meaningless for us. I think anyone that's ridden a bafang ultra can simply agree they have alot of ooomph.

But using NM it is still usefull in explaining the physical concept of what's happening in the drivetrain. How gear reduction/multiplication works. How force is converted from rotational to linear and back to rotational in the chain gear drivetrain. How changing the size of our front or rear gears affects gear ratios and also loads though the various components. These concepts are very important, and understanding them will help us improve the reliability of our bikes.

The absolute numbers don't matter. It's what is happening inside the drivetrain that is. And even more important than that, what we can do to increase our reliability.

 

[bram.biesiekierski]

I have looked at my setup, inspected what failed, and theorised why. I have applied some basic physics concepts to understand what's happening, and what I can do to improve my setup. I have now made the changes that I believe will increase reliability.

As I mentioned before. I have used a larger chainring than before, which will reduce the load into the chain, and into the cassette at any given gear ratio. I have explained exactly how this is possible earlier in this thread. I even explained how going from a 36t to a 44t chainring, and making a corresponding change at the cassette keeps exactly the same top gear ratio, while simultaneously reducing loads through the components.

I have used a thicker chain. Which is matched to a cassette with thicker teeth. Obviously increasing cross sectional area will spread loads over more material, reducing pressure on the contact points.

Both of these changes are a step in the right direction, and easily confirmed with simple physics concepts.

I have no way of measuring/comparing the different material properties, so I can only assume it's like for like.

 

[bram.biesiekierski]

160nm doesn't seem like that much... 205lbs person with cranks level if they stand on one foot that's 160nm torque. I'm like 215lbs and not afraid of that breaking a chain.

Heh googling, not sure if this is true:

> The German Industrial Standard sets minimum breaking loads for standard bicycle chains at 8,200 Newton and at 10,000 Newton for derailleur bicycle chains. The industry follows these standards pretty well.

And another site:

> Wippermann's internal standard is 9,500-11,000 Newtons of breaking force for its bicycle chains,

So 100kg person standing on pedals with the stock chainring, holding up ruler it seems roughly 87mm radius, that would be:

>>> 100*9.8*0.175/0.087
1971.264367816092

2000N on a chain rated for least 8000N? Doubling that for motor's 160nm torque still half what it should be rated for.

But not sure where this 160nm rating comes from really.. like 1000watts is 160nm toque with 60rpm cadence.. but like when struggling in climb at 30rpm cadence and bafang display says motor is doing 1000watts... how is not doing >160nm of torque? And like controller doesn't monitor phase current.. how would it limit torque? Maybe why stock controller sets Spd0's max current to 20%? As way to limit torque/heat at lower rpm? I'd guess if you raised up Spd0's max current you'd be more likely to break chains. But I dont' really have an experience with the stock controller.

FWIW I generally just try to be in a reasonable gear.. I actually find bike rides better with I target a higher cadence.. especially with shorter 160mm crank arms. Main thing through is when I do end up in the wrong gear, I don't rely on motor to power through. I'll jump off and redo whatever. Oh and when I had throttle hooked up I just avoided slaming on throttle when at a dead stop. First chain I think i got 800-1000 miles.. which seems pretty reasonable.

Interesting about the chain ratings. I never knew there were any standards that applied.

I would expect a 100kg person to be able to put even more than 170nm into the cranks. When peddling hard, you don't just stand statically on the crank arm and let gravity do the work. You stand up on it as it goes down, accelerating your mass up, as the peddle descends. And when your really cranking hard, you simultaneously tilt the bike over, away from the pedal that is descending. This will increase the force into the cranks even more.

As for the 160nm, that's Bafangs claim. I don't think we have any way of measuring this, or confirming it, or even what RPMs it may happen at. Although I do see your point about it being odd that the same power in, at different RPMs, is still potentially producing the same torque. You would assume the with same power in, it would result in twice the torque at half the RPM, or half the torque at twice the RPM.

I think one difference with the motor output vs human output, that makes it feel more powerful, is that the output is continuous through the rotation. Whereas human output would have 2 distinct peaks per revolution.

In my experience, it wasn't the chain that had problems. My cassette teeth wore down and rounded over at the tips. So bad that the chain was skipping over them with high motor output and / or assist. It was happening on all the highest 5 or 6 gears. And it happened in less than 50kms of use!

 

[agro_86]

I would appreciate it if this post could be shared to the relevant Dengfu E10/Cheeb threads on the forum. Nevertheless,
View attachment 92297
This is the DZ41 display. A display which CANBus protocol bafang emtb riders have been waiting for.
View attachment 92298
Power button is located on the bottom of the display.
View attachment 92299
The display uses a 2.5mm allen key to secure onto the handlebars.
View attachment 92300
Please note, the display does not include a 2.5mm allen key (nore introductions for navigation).

The DZ41 display I opted for is the CANBus protocol.
View attachment 92301
However, you can get these displays in the UART protocol.
View attachment 92302
Connecting the display onto the E10 took less than 5min (obviously factoring in your cockpit preferences).
View attachment 92303
Although the display cable isn't straight in the above pic, the cable is measuring at 56.5cm
View attachment 92304
Plenty long enough to be mounted on my 820mm 35mm Raceface Atlas handlebars outboard.
View attachment 92305
The buttons have a good tactile response (a satisfying click). Ergonomically moulded perfectly for your left thumb to press the up or down button without fear of accidentally pressing the opposing button.
View attachment 92306
The above image probably doesn't show how clear the display is when booted up. However, all readouts to my eyes are clear and big to see.
View attachment 92308
Battery level is shown in 20% increments on the bottom. PAS level is shown towards the top left in red. The speedometer is shown in the middle.

Advanced settings of the display can only be accessed within the initial 5sec of booting up the display. Simply power on the display and then hold the mode button *M* for 3sec. You'll then be able to go into the parameters of the display such as:-
*Imperial or Metric
*Auto off time period
*Top speed adjust (only the UART variants can adjust top speed)
*Wheel size (only the UART variants can adjust wheel size)
*Wheel circumference (only the UART variants can adjust the wheel circumference).

Sadly, there doesn't seem to be an ability to adjust screen brightness. But by holding up to activate the light feature, it will dim the display.
View attachment 92309
Just in case if anyone wants to know the serial number of the CANBus version of the DZ41 display.

Anywho, I'll make a full vid explaining everything and compare the DZ41 display to other displays from bafang along with other manufacturers.

Any questions, feel free to let me know.

Again, please share this information to the relevant threads

Hi Neeko
I am in the process of ordering all my parts for my E22 build. I like the look of this display and it's perfect for me because ill be using 35mm bars for the build. I noticed that in the very early stages of your build some photos show you using the 500c display with a round UART type plug and in this post I see that you ordered a CANBUS type plug. I'm wondering firstly if somehow you managed to integrate them which I'm thinking is unlikely. More importantly if you are using the CANBUS version of the M620 have you or anyone else here succeeded in tweaking the motors torque setting on the CANBUS version. My M620 has already been shipped and by the time I found out mine is the CANBUS plug it was too late todo anything about it.

 

[Neeko DeVinchi]

Hi Neeko
I am in the process of ordering all my parts for my E22 build. I like the look of this display and it's perfect for me because ill be using 35mm bars for the build. I noticed that in the very early stages of your build some photos show you using the 500c display with a round UART type plug and in this post I see that you ordered a CANBUS type plug. I'm wondering firstly if somehow you managed to integrate them which I'm thinking is unlikely. More importantly if you are using the CANBUS version of the M620 have you or anyone else here succeeded in tweaking the motors torque setting on the CANBUS version. My M620 has already been shipped and by the time I found out mine is the CANBUS plug it was too late todo anything about it.

Apologies for the delay @agro_86.
The full video regarding the DZ41 display will drop tomorrow. I opted to test the CANBus version, as most new models of motors from Bafang are using CANBus protocol. As such, the display has been installed on my E10v1.
My E22 is running the UART protocol which explains why I'm able to use the 500c display.
Sadly, development of an adapter cable from UART to CANBus and vice versa is proving tricky.

Granted, the wiring schematics aren't difficult to understand. Moreso, it's the interface in terms of functions of the display which is proving to be the complex matter. But I'll spread the word of any developments.

For now (not to give anything away), this will be the display I'll use on any CANBus protocol bafang ebike.......until something better comes out

 

[Mabman]

"More importantly if you are using the CANBUS version of the M620 have you or anyone else here succeeded in tweaking the motors torque setting on the CANBUS version."

Didn't notice Neeko addressing this so I will jump in to say a hard no to CANBUS tweaking but it is being worked on. The only way to +/- motor torque is to adjust the Amp level limit which is possible on UART. I am not sure what Amp level the CANBUS motor comes programmed with but my UART stock was 30A and I believe Neeko said awhile ago he had reduced his to 20A? Regardless it really isn't an issue because all you have to do is select a lower assist level which will decrease available torque also. It's not like you have 160nm torque on tap at all times.

Being able to tune the PAS and throttle output settings to an individuals preference which CANBUS at this point doesn't allow as UART did is the main issue it seems.

 

[Neeko DeVinchi]

@Mabman is correct. Progress by myself and fellow fanatic bafang users Is slow.

To put context to our perdicament, I'll share some images which highlights differences between the UART M620 & CANBus M620

 

[Mabman]

Just be aware that if your M620 Ultra controller goes bad then it is not a 5 minute fix. More than likely will require a shipping fee/time expenditure to send it to a qualified service facility as the new controller has to be calibrated to the motor. Best to do this ASAP as issue is diagnosed. Ask me how I know or just bear in my pain at losing my bike at prime riding time here, feels like I just scratched in the TDF due to a mechanical

 

[rivets]

Just be aware that if your M620 Ultra controller goes bad then it is not a 5 minute fix. More than likely will require a shipping fee/time expenditure to send it to a qualified service facility as the new controller has to be calibrated to the motor. Best to do this ASAP as issue is diagnosed. Ask me how I know or just bear in my pain at losing my bike at prime riding time here, feels like I just scratched in the TDF due to a mechanical

Good to know. Sounds like a good opportunity to get it innotraced or archon'd, if it hasn't been already?