Wisper rear Bafang and front Dapu motors.....

[flecc]

Wow! That is huge Flecc, though I think I can guess the bike!

All the best

David

Sadly it's no better with the latest batteries higher capacity batteries, due just to a fundamentally greedy combination of design factors.

However, it's valuable in the way it shows how vital even the smallest design details can be to getting the best possible compromise of all performance factors in a very limited power vehicle.
.

 

[Wisper Bikes]

Anecdotally, our clients report numbers which imply anywhere between 5 and 8 Wh/mile. What about yours, David?

It so depends on the use and assist setting Bruce, our top level of assist is very powerful and produces a lot of torque. Hence the 6 levels of assistance on the Alpino bikes.

We have achieved figures of 6 and 7Wh/m and I know we can improve massively on that, however what's the point? Anyone can restrict the amount of power available to the motor to the point where there is no assistance.... we could achieve 0Wh/mile or even less with a regen! On a tough ride can go to as many as 15+Wh/mile on full assist and no doubt more. The point is we offer the choice to the rider.

Obviously I would rather not give too much away!

Best regards

David

 

[NRG]

Yes, and remember it's continuous use of the battery that's relevant, IE taking it to an extreme a rider could go 35 miles or more with no assist and then use all of the battery in the last mile climbing a 'wall' (with no limit on the controller)...the consumption should be measured over that last mile.

Also, there comes a point where assistance is so low that it's of no practical use, getting to 5Wh / mile on a hub powered bike is boardering on the "is it worth it" 'line. Even the super effective Panasonic system which gets down to around 7Wh is questionable at this point although it's certainly more effective driving through the gears than a hub system.



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Posting from my iPhone using Tapatalk

 

[rog_london]

Funny, isn't it, how so many people never get a grasp of the compromises which come into play on designing and riding ebikes!

(1) To get the best out of any bike - with or without a motor - you've got to be prepared to pedal. The more effort you can put in, the more rewarding the experience will be.

(2) Raising the top assisted speed even a little bit will cause the battery to have a much harder life - out of proportion to any speed advantage you may gain - see part 1!

(3) If you really *need* an invalid scooter, don't buy an ebike. You'll be disappointed. See part 1!

(4) Irrespective of the motor, controller or bike, buy the biggest capacity battery you can get. The increase in range and battery lifetime far outweighs the increase in capacity.

(5) Weight is an even bigger problem for an ebike than it is for you. Go easy on the pies.

These aren't hard and fast rules. They're also just my opinion, and if you think I'm talking rubbish you're welcome. I know there are some on here with quite serious physical disabilities who manage ebikes very well - they have my admiration, and it goes to prove that determination can overcome many obstacles.

Apart from that if power and speed are what you crave buy a moped, and progress to a motorbike. Even a small motorbike will leave an ebike for dead. You shouldn't be looking to cheat the system on a machine which is, or should be, designed for a specific purpose. Much over 15 MPH and you're on your own, or you ought to be.

Rog.

 

[Wisper Bikes]

Funny, isn't it, how so many people never get a grasp of the compromises which come into play on designing and riding ebikes!

Rog.

Absolutely Rog, that is what makes it so interesting, an art rather than a science.

I think most of us try to be all things to all men when we should probably be specialising at one end of the scale or the other, the super light bike with a little extra boost or a virtual moped.

There is no doubt that both will sell well. As the market becomes more sophisticated I am sure these different styles will develop.

All the best

David

 

[flecc]

That's certainly not rubbish Rog, it's all good sound commonsense.

As I so often observe, these are electric-assist bikes, not electric bikes and not pedal-assisted bikes.

In other words the sole function of the electric motor is supposed to be assisting what is fundamentally a human powered bike.
.

 

[rog_london]

Absolutely Rog, that is what makes it so interesting, an art rather than a science.

I think most of us try to be all things to all men when we should probably be specialising at one end of the scale or the other, the super light bike with a little extra boost or a virtual moped.

There is no doubt that both will sell well. As the market becomes more sophisticated I am sure these different styles will develop.

All the best

David

I have the feeling that the 905SE was designed with you in mind! With me on board it goes like a ferret up a rat hole....

If that's not a product endorsement I don't know what is.

Rog.

 

[Wisper Bikes]

Do you know, every so often a perfect post is made on this site, thanks Rog for another. That's put me in a great mood for the rest of the night!!

Splendid!

David

 

[umazooma]

dapu and bafang

Apart from rubbish names for the European & N.American markets, i have used both on front wheels and they both work fine for at least 18 months without abuse. Dapu seems to be Japanese but i believe construction, like much Shimano stuff, takes place in mainland China. The Dapu is noisier that is for sure. The build quality seems to be very similar but i prefer the Bafang because the power cord does not come out of the centre of the axle which goes against my sensibilities. To my understanding you cannot consider a motor without considering its controller so power and efficiency comparisons are hard. I find Bafang smoother and i do not use Hall sensors on either. The Dapu website is not very helpful. If you wish to soup up either of these motors, i suggest getting a thermal cut out fitted inside or to the surface of the hub to avoid cooking everything.

 

[Wisper Bikes]

I agree Umazooma, 8fun?? I think Ba is Chinese for 8 or similar and fun sounds like fang! That was the reason I was given anyway! IMO Bafang sounds much better.

The Dapu motors are made at Dapush or Dapu Shanghai to exacting Japanese standards, we even have to wear slippers in the factory! This is the same factory as all the circuit boards for virtually every Japanese washing machine, A/C unit etcetera that you have ever heard of come from. I believe Dapu motors though expensive are simply the best in the world, especially the new breed now on the market. Dapu don't encourage anyone to soup up their motors but they are amazing when working with a manufacturer.

Dapu have just started manufacturing a new controller which quietens the motor noise considerably, their hall effect motor just about to be launched is near silent. We have run massive currents through these motors for long periods of time and simply cannot cook them, however the control system we use will not allow the throttle to be used when the bike has been immobilised or the demand is very high, such as a large rider starting of on a very steep hill under throttle only. We utilise the hall effect 350W Dapu in Canada and USA which has truly amazing torque.

Bafang make splendid motors considering the cost, not as bullet proof as Dapu but not bad at all.

All the best

David

 

[Oxygen Bicycles]

If I can squeeze my two words about Dapu I can also confirm they made in Shanghai by Chubutsu Electronics originating from Japan but now producing in China. Chubutsu / Dapu mainly makes the motherboards for air conditioning, fridges and dishwashers but they also make quite good motors.

And yes you have to wear a slippers in the factory that just proves how good they are about standards and quality. The Dapu / Chubutsu team are very friendly with MD from Japan and bunch of very smart Chinese engineers that currently work damn bloody hard to improve and eliminate the issues they had with their motors ( I mean noise and poor throttle performance)

At the time I visited the factory I wasn't prepared to use them as I found above mentioned weak points too significant but currently I know Dapu improved massively and I look forward to visit them again on my next trip to China. I'll report soon I put my hands on the new Dapu.

Merry Christmas to you all

Andrew

 

[Wisper Bikes]

It is nice to hear from you again Andrew, I was told that you were staying in Europe more and more now?

It is strange but for the last year or so we have only had superb kit from Dapu, very much better than Bafang. I am always flattered Andrew by the way you like to emulate our bikes!

I see from your signature that you are now a member of BEBA. I wasn't aware. Welcome, we are really doing a lot in 2012 to promote electric bikes, good to have you on board.

All the best

David

 

[Oxygen Bicycles]

nothing to emulate about your bikes David , we are now introducing our own range of motors with internal ratchet clutch and no drag at all, defo moving away from 8FUN and very glad Dapu is improving too. I really like the DAPU team and certainly respect them for their potential and capabilities. 8FUN have been in the motor industry for forever, Dapu in a lot shorter time seems they already took over Bafangs by miles away.

I also see you have an intelligence working very well for you and certainly know where it's coming from, good to know now but yes I try to spend bit more time with my lovely little boy now when its more quiet so yes spending my time half UK, half EU.

all the best and Merry Christmas, speak soon

Andrew

 

[Kenny]

Quote; we are now introducing our own range of motors with internal ratchet clutch and no drag at all,

Hi Andrew, please keep us updated on your new motors. As a keen cyclist, the one thing that has always put me off hub driven bikes is the motor drag, so it sounds like a great developement.
The Tongxin is the only one to interest me previously, but from what I've read their reliability is not up to scratch with other motors. I'm suprised the Tongxin hasn't been developed further to "beef it up" because otherwise, with its light weight and zero drag, it ticks all the boxes.

 

[Mussels]

Hi Andrew, please keep us updated on your new motors. As a keen cyclist, the one thing that has always put me off hub driven bikes is the motor drag, so it sounds like a great developement.
The Tongxin is the only one to interest me previously, but from what I've read their reliability is not up to scratch with other motors. I'm suprised the Tongxin hasn't been developed further to "beef it up" because otherwise, with its light weight and zero drag, it ticks all the boxes.

I've got one of the first Dapu motors Wisper used and it's a massive improvement over the SB, I used to hate riding without power but with the Dapu motor the 'wading through treacle' feeling seems to have gone and it's more like riding a heavy bike.

 

[eddieo]

I've got one of the first Dapu motors Wisper used and it's a massive improvement over the SB, I used to hate riding without power but with the Dapu motor the 'wading through treacle' feeling seems to have gone and it's more like riding a heavy bike.

Yes my DaaHub with front Dapu motor feels better then the bafang....Unrestricted it has a lot more get up and go as well!

 

[Kenny]

Thanks Mussels and Eddie, I'd love to try it side by side with my PCS for a direct comparison. Unfortunately, where I live, I seem to be the only ebike rider.

 

[Wisper Bikes]

Thanks Guys, it is am amazing motor, by far the best we have ever tried. We have been working very closely with Dapu over the last year and have stopped using the old out sourced controller in favour of a new Dapu controller, it manages the system very well, gives superb diagnostic facilities and has quietened the motor quite dramatically. The other huge advantage of using the dapu motor is the very low drag when cycling without power.

The new 905sel utilises the latest rear motor from Dapu, the torque is insane. We are lucky to have recently received rave reviews in the French cycling press for the bike which I have to say is absolutely fantastic, it whips my not inconsiderable (19stone) bulk up and down the north downs in Kent with ease. We really do need to get on with promoting this bike!

All the best

David

 

[Wisper Bikes]

Oh and thanks Andrew, Merry Chrismas to you and your family too!

Best regards

David

 

[Deleted member 4366]

Hi Andrew, please keep us updated on your new motors. As a keen cyclist, the one thing that has always put me off hub driven bikes is the motor drag, so it sounds like a great developement.
The Tongxin is the only one to interest me previously, but from what I've read their reliability is not up to scratch with other motors. I'm suprised the Tongxin hasn't been developed further to "beef it up" because otherwise, with its light weight and zero drag, it ticks all the boxes.

I have to say it again, because I still think there's a few myths floating round, probably based on something from history. I've ridden loads of hub-motored bikes with nearly all the Bafang variants, plus other manufacturers and I've never noticed any drag on any of them bar one 350w BPM that had some insignificant drag that I noticed when it was new, which loosened up after about 100 miles and then became unnoticeable to the extent that I just about hit 40mph free-wheeling down a long hill. Strangely, my clutch jammed a couple of times, which I knew because I could hear the motor turning while I free-wheeled, but I hardly noticed any drag. Please don't draw the conclusion from this that I'm incapable of noticing drag!