Is there any hub drive bike worth paying more than £1700?

[GaRRy]

I think we are at cross purposes here, risking comparing apples with oranges. A hub motor alone cannot be fairly compared with a crank drive unit.
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Agree and also going way of topic again as the question was not about the relatve merits of Hub V Crank but whether there is a market for £1700 + Hub Bikes.

 

[flecc]

Yes, I forgot about that one, but even then we've know idea about whether it had been interfered with. It's easy to re-route the wiring wrongly if you take the wheel off to fix a pucture oy whatever.

And of course I wasn't speaking of motor water ingress which is fairly rare. As can be seen, I was speaking of whole system water ingress causing connection/shorting problems.

 

[flecc]

Agree and also going way of topic again as the question was not about the relatve merits of Hub V Crank but whether there is a market for £1700 + Hub Bikes.

The matter is related though, Kudos clearly asked in the context of named crank drive bikes, prices in comparison.

 

[NRG]

Because it has massive torque and a lot of power, so if anybody can figure a way to get a EN15194 certificate, as has been achieved by BH Emotion, then they have a big sales advantage. You only have to ride one to see what I mean. It's a similar situation with the Heinzman motors, which can somehow run legally at 28amps with 36v = over 1KW fromthe battery. They also climb pretty well - not surprisingly.

Yes I understand that what I don't understand is how it passes the current EN regs.

 

[jhruk]

Even testing using the method in 4.2.7.2 required the motor to produce no more power than 250w +10% under the current regs. Now, I'm aware this may change in the future but today even with a current limiter / soft start / current map or whatever you must limit amps.

My reading of this, admittedly only brief, is that for the purposes of the regulation the maximum power at the wheel can be determined solely by the acceleration test in D3. I don’t see anywhere that this test requires current measurement to determine maximum power …but I may well have missed something.

 

[flecc]

Yes I understand that what I don't understand is how it passes the current EN regs.

How do any of them pass? Given that they easily have 75% efficiency, some better, 36/37 volt systems should be limited to controllers of around 9 amps capability to output no more than 250 watts maximum continuous power.

In practice today's "legal" e-bikes mostly use controllers with between 12 and 20 Amps continuous capability, the odd ones with up to 30 Amps. It baffles me how the testing labs manage to "lose" up to two-thirds of the net power output.

My reading of this, admittedly only brief, is that for the purposes of the regulation the maximum power at the wheel can be determined solely by the acceleration test in D3. I don’t see anywhere that this test requires current measurement to determine maximum power …but I may well have missed something.

Some at least of the issued certificates on these over-powered bikes state the output was measured at the motor shaft, clearly impossible to do anyway on some of the designs in question. With such indications of truth-stretching present, it's likely that the labs practice some extreme tolerance in their measurement techniques.
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[NRG]

Torque is directly related to current, acceleration is related to torque so limiting current will limit the acceleration.

 

[NRG]

How do any of them pass? Given that they easily have 75% efficiency, some better, 36/37 volt systems should be limited to controllers of around 9 amps capability to output no more than 250 watts maximum continuous power.

In practice today's "legal" e-bikes mostly use controllers with between 12 and 20 Amps continuous capability, the odd ones with up to 30 Amps. It baffles me how the testing labs manage to "lose" up to two-thirds of the net power output.

Exactly, that was what I was driving towards Flecc...

 

[flecc]

And of course the other simple proof is that the actual continuous hill climb performance proves that well in excess of 250 watts continuous net output is present on almost all e-bikes. Double is far from uncommon.

 

[Deleted member 4366]

Torque is directly related to current, acceleration is related to torque so limiting current will limit the acceleration.

All you have to do is put a ramp in the controller's power algorithm so that when you open the throttle fully, instead of giving full power you only get it slowwly ramped up. For the few seconds of the test, only a slight ramp is enough to get a pass. The ramp actually makes the bike more controllable and can be applied to the throttle or PAS.. The requiremnt of the standard is that the motor should be labelled as being rated at no moore than 250w, so you take the 350w label off and put a 250w one on. The manufacturer can decide on the rated power of their motors, so they can put on whatever label they want - hence the BPM now being available in "250w" version, but it's the same size weight and power as the 350w one as far as I can tell.

 

[flecc]

That's the sort of "stretching" I'm speaking of above, a few seconds of test only to specify the continuous maximum power is clearly not in compliance with the requirements of the construction and use law.

 

[NRG]

Makes a complete mockery of the EN regulation. The sooner the 250w limit is removed the better... Also prospective purchasers of 'EN certified' bikes should take that particular sales pitch with a large bag of sodium chloride.

 

[funkylyn]

All you have to do is put a ramp in the controller's power algorithm so that when you open the throttle fully, instead of giving full power you only get it slowwly ramped up. For the few seconds of the test, only a slight ramp is enough to get a pass. The ramp actually makes the bike more controllable and can be applied to the throttle or PAS.. The requiremnt of the standard is that the motor should be labelled as being rated at no moore than 250w, so you take the 350w label off and put a 250w one on. The manufacturer can decide on the rated power of their motors, so they can put on whatever label they want - hence the BPM now being available in "250w" version, but it's the same size weight and power as the 350w one as far as I can tell.

Where exactly are these motors being tested ?

Surely not in the E.U. ?.......must be in China lol

Wherever it is....... its sounding more interesting to me by the minute

So ......are you saying that actually now a LOT more bikes are arriving with these more powerful motors masquerading as 250's ?

Or is it still just odd ones ?

If so, it rather makes a mockery of the legal/illegal bike debate that a lot of people like to take umbrage with

Lynda

 

[flecc]

It's a variety of independent laboratories Lynda, usually in Europe.

As I remarked above, almost all e-bikes output well over 250 watts, your Tonaro does. With only 250 watts it would struggle to pull the skin off a rice pudding.

I think the legal/illegal bike arguments are mostly centred on the speed issue more than power.
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[funkylyn]

It just sounded to me flecc that dave was talking about a specific motor that was a LOT more powerful, as opposed to the 'nominally' more powerful motors we have at the moment.

Interesting that they are being tested in Europe.

I wont even try to go into the legal/illegal argument again......I dont feel fit enough at the moment .......suffice to say that I am looking forward to trying a hub motored bike with a 'legal' but MUCH more powerful motor.......that is legal !

They really need to sort these laws out sooner rather than later....its patently ridiculous.....

Lynda

 

[flecc]

They are already here Lynda, and not only the BPM motor that Dave is speaking of. He also mentioned the Heinzmann hub motor, and the eZee one delivers at least 550 watts of net power, all certified legal.

If the move by the European parliament to have all power limits removed isn't enacted, and I doubt it will be, the existing power law is unlikely to be sorted out. Complacency rules while those in power think it's working.

 

[funkylyn]

I already know about the eZee one....so which is the more powerful then..........eZee or BPM ?

Lynda

 

[flecc]

I don't know the usual controller's current rating for the BPM motor, I'd guess it must be at least 20 Amps and up to 30 Amps. The present eZee controller is a 20 Amp one, but some while ago they used a 30 Amp one on some models, In very rough terms with a nominal 36 Volt battery:

20 Amp controller = 720 watts consumption = 540 Watts power output

30 Amp controller = 1080 Watts consumption = 810 Watts power output
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[funkylyn]

Thanks Flecc

Lynda

 

[jhruk]

Maybe the EN test is similar to an MOT in that it depends where you take it - and helps if you know the tester.