Tour of Britain – Stage 3 , eZee vs Kalkhoff

[flecc]

Assuming that your 8FUN motors are similar to the new eZee motor and current limit is set to about 21 Amps then peak power would be just at the point when the current limit comes off. That's about 18 mph. Below that speed, power and efficiency are reduced (at full throttle). In fact at 478 watts the eZee motor would be doing about 10 mph at 68 % efficiency (ebikes.ca sim).

Different bike John, my non-pedalling motor only measurements are primarily on the Quando, same battery, controller, motor set, but the motor in a 20" wheel. Also this original Quando/Torq motor is not as you describe the new eZee motor, the peak power occurring in the Quando at just about 10 mph.

The Torq 1 isn't a bike on which practical motor only climb measurements can be made, since it only just about reluctantly manages 6%. The Quando with it's normally geared motor in the 20" wheel enables practical measurements at and on both sides of the peak power point without any pedalling need, so no guesswork.

There's a lot that's odd about this matter. For example A to B couldn't have got their 576 watts measure from the restricted current since the restrictor didn't exist at the time of their Torq test. Their Torq was a prototype made from a Quando electrical set which has no restrictor, and they use a DrainBrain (now CycleAnalyst). There's also long been a misunderstanding about the Li-ion cutting out and the associated manufacturer's pursuit of maximum current delivery. That was never the problem, plenty of current available initially, even the earliest battery easily capable of over 20 amps. The problem was one of chemical tiring under sustained load over time dropping the voltage below safety cutout point.

As ever, I opt for the practical, and I'm happy with knowing the power that I actually get from my two eZee motors. I'm not too worried about how much they waste when vehicles of up to hundreds of kiloWatts are flying past me all the time.
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[john]

I'm not too worried about how much they waste when vehicles of up to hundreds of kiloWatts are flying past me all the time.
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I'd certainly go along with that. The main issue with e-bike efficiency being the range obtained from a given battery.

 

[john]

The Torq 1 isn't a bike on which practical motor only climb measurements can be made, since it only just about reluctantly manages 6%. The Quando with it's normally geared motor in the 20" wheel enables practical measurements at and on both sides of the peak power point without any pedalling need, so no guesswork.

That's something that's been puzzling me for a while. If a Torq 1 can only manage 6%, doesn't that mean that a Quando should only be able to manage about 8-9% ? But I'm sure you said it could do much better than that.

 

[coops]

One factor is that a Torq1 uses more power just to move along at climb speed, so has less power available to actually climb with & so will manage lesser gradients that the relative gearing difference might at first suggest.

I imagine there are probably other subtle factors too which together might account for any observed difference.

I'll post on the main thread topic next chance I get, though I'm afraid the several long 10-15% climbs with parts maybe up to 20% would be beyond me on my Torq1 at the moment, maybe even with Torq 'hill-climb' batteries...

Stuart.

 

[Gaynor]

We no longer stock ezee battery but we will buy some at £150.

I noticed there were no batterys for sale, 150 sounds very reasonable.

 

[flecc]

That's something that's been puzzling me for a while. If a Torq 1 can only manage 6%, doesn't that mean that a Quando should only be able to manage about 8-9% ? But I'm sure you said it could do much better than that.

The Quando with my 70 odd kilos and a few other bits can climb 12% unaided with ease and just about scrape a 14% for a while. A to B findings are the same.

The Torq gradually dies to a stall on 7% and is not confident on 6%. This is simply because it's motor is so grossly overgeared for the power to weight, torque and power curves etc. Ask anyone in motor sport and they regard gearing anything up by 10% as a bit extreme, but the Torq is geared up by 40% from the ideal of the Quando.

Another pointer to this is the maximum speed. On a good Li-ion battery fresh off the charger the Quando will run up to over 18 mph on the flat in still air. On the same battery in the same conditions the Torq should run up to over 25 mph, but as any owner knows, about 22 is the limit and then only when everything is favourable.

In fact if the Torq had a 26" wheel instead of 28", it would still have the same top speed and climb better, and would almost have the same top speed with a 24" wheel and climb even better yet, again indicating how over the top that 40% overgearing is. I posted all this well over a year ago, but at that time the Torq craze was at it's height and no-one would agree. Of course they didn't have Quandos with the identical electrics so weren't in a position to judge, though happy to say I was wrong.
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[john]

The Quando with my 70 odd kilos and a few other bits can climb 12% unaided with ease and just about scrape a 14% for a while. A to B findings are the same.

The Torq gradually dies to a stall on 7% and is not confident on 6%. This is simply because it's motor is so grossly overgeared for the power to weight, torque and power curves etc. Ask anyone in motor sport and they regard gearing anything up by 10% as a bit extreme, but the Torq is geared up by 40% from the ideal of the Quando.

Another pointer to this is the maximum speed. On a good Li-ion battery fresh off the charger the Quando will run up to over 18 mph on the flat in still air. On the same battery in the same conditions the Torq should run up to over 25 mph, but as any owner knows, about 22 is the limit and then only when everything is favourable.

In fact if the Torq had a 26" wheel instead of 28", it would still have the same top speed and climb better, and would almost have the same top speed with a 24" wheel and climb even better yet, again indicating how over the top that 40% overgearing is. I posted all this well over a year ago, but at that time the Torq craze was at it's height and no-one would agree. Of course they didn't have Quandos with the identical electrics so weren't in a position to judge, though happy to say I was wrong.
.

I wouldn't expect the Torq to go 25 mph, 40% faster than the Quando, because power requirement does not increase linearly with speed. However, thrust required (often loosely referred to as torque) does increase linearly with slope and the thrust produced by the Quando should be about 40% greater than the Torq, meaning 40% greater climbing ability (actually a little better than 40% due to the lower wind resistance at lower speed).

I don't for a minute doubt your measurements, but to me, the reason still remains a mystery.

 

[flecc]

I wouldn't expect the Torq to go 25 mph, 40% faster than the Quando, because power requirement does not increase linearly with speed. However, thrust required (often loosely referred to as torque) does increase linearly with slope and the thrust produced by the Quando should be about 40% greater than the Torq, meaning 40% greater climbing ability (actually a little better than 40% due to the lower wind resistance at lower speed).

I don't for a minute doubt your measurements, but to me, the reason still remains a mystery.

Of course John, but the speed loss is still far greater than would be expected and it's due to the over gearing of that motor in the Torq 1. The wheel size examples illustrate that, the same speed available at 20% overgeared and almost the same at only 10% overgeared. That is the clearest possible evidence of the overgearing of 40%.

The experiences aren't just mine of course, David at A to B has exactly the same experiences with the prototype Torq 1, a later model and an early Quando.
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[john]

Had a look back and found this post...

4) Rider unfit, early 60s, 20 stone/ 127 kilos

Torq: 1 in 13.3/7.5%, Sprint: 1 in 11/9%, Quando: 1 in 9.4/10.6%

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...which is more what I would expect.

 

[coops]

I did a very quick & rough Gmap of the route, with elevation profile 'Tour de France/Britain' style .

I'll try to do a more accurate one for better profile & double check the route.

No overall height gained shown sadly, but looks to be (roughly) at least 1250m of ascent, at least one climb (the last one...) being a long 10-14% stretch with several 14-20% graded sections.

Stuart.

 

[ElephantsGerald]

I did a very quick & rough Gmap of the route, with elevation profile 'Tour de France/Britain' style .

I exported your GMap route as a GPX file and shoved it into www.Bikely.com to get the following elevation profile:


Looks reasonably painful!

Regards,

Elephants

 

[Tiberius]

Hmm,

I get worried when I see the words "painful" and "reasonably" in the same sentence.

Coops, Elephants, am I doing something wrong; those links don't seem to take me to the right place?

Nick

Now, where did I put those performance enhancing Lithium based chemicals?

 

[ElephantsGerald]

Coops, Elephants, am I doing something wrong; those links don't seem to take me to the right place?

My link to www.Bikely.com takes you to the front page of the Bikely web site, where you can register and log in.

I've just made this route publicly visible in Bikely, so you should be able to see it here. Click on Show/Elevation Profile to see the elevation graph.

Regards,

Elephants

 

[flecc]

Had a look back and found this post...



...which is more what I would expect.

But that's with the rider input as well John, a hopelessly inaccurate way of measuring motor ability.

I would never measure motor ability that way, and as I said above, I'm speaking of motor only measurements, without any pedalling.

The post you quote is of expectations of a rider and motor combined, which in that case greatly favours the Torq 1 since the rider has gears, the Quando only having a single 70" gear. Therefore it's got no chance of reflecting the motor's relative ability in the two bikes, with both the gearing mismatching and rider input corrupting the outcome. In fact with those factors taken into account, it proves how poor the Torq 1 motor's climb ability really is
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[coops]

Thanks Elephants

I've redone the route with more points to try to improve the profile accuracy:

Gmaps
Bikely

Both should be publicly viewable, the bikely profile looks little different from before & is rather too stretched vertically to be useful, but the total ascent now given as 1980m the Gmaps profile gives a better impression of the terrain in my view, and the redone route shows some gradients/small hills which may have been smoothed over in the earlier rough & ready profile... some of it is probably not entirely accurate, as sanoodi showed, and doing it without any contours visible doesn't help, but I'd say its at least a guide.

So thats close to twice the total climb of the Alpe d'Huez and 14.5 times the total distance traveled, or over twice the Jurassic Test climb, and nearly 4 times as far...

Hope you're seeing them ok now Nick? If so, you might have some ideas where to put those performance enhancing (lithium) chemicals...

Stuart.

 

[Django]

Brilliant effort Coops & Elephants, thanks.

Related, this Tour de France street level view is fantastic.

 

[coops]

I think we're a step closer to doing a 'virtual' test... almost as good as watching it on the telly! .

Stuart.

 

[stokepa31_mk2]

Cycling plus this week is plugging a 3000 rider public stage of the tour calling it a mass participation event. it will be a rerun of the yorkshire stage starting in hull. september 21st is the date. perhaps an organised event would allow more ebikers to take part. Tour Ride 2007 will have details soon

 

[stokepa31_mk2]

Route

Okm Kingston upon Hull 10:00
10km Barton-upon-Humber : Sprint 10:45
15km Barrow-upon-Humber 10:50
30km South Ferriby 11:10
53km Beverley 11:45
74km Hornsea 12:15
96km Bridlington : Sprint 12:45
116km Filey 13:15
126km Scarborough : Sprint 13:35
138km Falsgrave : KOM 13:45
152km North Side : KOM 14:05
155km Dalby Forest : KOM 14:10
168km Dalby Forest Visitor Centre 14:30


Links
Welcome to Hull & East Yorkshire | Official Visit Hull and East Yorkshire Tourism Website

 

[Tiberius]

Cycling plus this week is plugging a 3000 rider public stage of the tour calling it a mass participation event. it will be a rerun of the yorkshire stage starting in hull. september 21st is the date. perhaps an organised event would allow more ebikers to take part. Tour Ride 2007 will have details soon

Now that would be neat, a mass participation event - provided there was a class for ebikes, or even just ebikes allowed to join in and form their own class. As I said earlier in the thread, and event of a different format to the Tour de Prestiegne, and at the other end of the season, would be good.

I notice on the T de F, there are motorbikes in amongst the riders with cameramen on the back. Suppose we had them there in a big ebike marathon. Every so often the pillion rider could hand a charging cable across to the ebike. Mid-air refuelling!

Nick