Latest designs...

[JohnInStockie]

Hi everyone,

Thought I'd start a thread on the latest designs to the market and ask a couple of questions/opinions.

Looking at the new Torq Trekking and the Forza, both bikes now come in at over 25Kg and both have front hub motors. How does this effect the bikes ridability when the battery power is gone do people think?

Also of interest to me is the Wisper 905e/905se, and looking at the Forza vs the Wisper, is there much in it between those 2 bikes? The Wisper comes in at 22.6Kg vs the Forza's 26.3Kg, and of course the Wisper has a rear hub motor. How much could these factors effect the ridability of the bike?

With all 3 bikes, and the current trend towards hub motors and all the advantages that they bring with reliability, are trends moving away from 'power-assisted' pedal bikes and closer to motorised-bikes with pedal assistance of the motor (the difference being that in one the motor is helping the rider, whislt in the other the rider is helping the motor)?

What are peoples thoughts on this?

John

 

[Ian]

My own veiw is that e-bikes should be bicycles with a motor to help out when the going gets tough and I feel my Torq is just that. I agree that the latest batch of bikes give the impression of being motorcycles with pedals which aren't really to my taste.

On the subject of weight obviously lighter is better but while a couple of kg is very relevant to a racer how much difference does it really make to a loaded e-bike. By the time I'm loaded with a spare battery, locks, wet weather gear, drinks, sandwiches etc a small weight saving becomes insignificant, yet I still do what I can to save weight!

I guess I'm probably in the minority, judging from many posts it seems that a lot of users want as much power as possible, perhaps the nearest thing to a motorcycle without the hassle.

 

[JohnInStockie]

Just to follow up on the question I'm asking above, its interesting how the trends are moving away from bikes like the crank drive Giant Twist, and more towards the hub drive due to their reliability advantages due to simplicity. However, it is interesting how the hub driven bikes with their inbuilt gearing resistance to riding without power and suspension, would seem to be going in completely the opposite direction to what most would regard as a 'power-assisted bicycle', which probably the best example I know of would be the Cybien seen here.

Why does this seem to be happening?

What insights can we make from the people buying these type of bikes, why are they successful?

Anyone have any thoughts?

John

[Ian - just overlapped your post ]

 

[Ian]

The concept of the Cybien appeals to me a great deal but I have reservations about the drive method. The reality is that hub motors work extremely well and most offer negligible resistance when freewheeling, if the Cybien had a compact hub motor it could be a serious contender for my money, especially as the new Torq has been spoilt with suspension.

 

[fishingpaul]

i think most people, want a bike that rides well on the flat without assistance from the motor, but is easy to ride up a steep hill,personally i brought an electric bike for exercise,after thinking i could still ride up hills, after a 20 year lay off from cycling.obviouslly i could not do this with a conventional bike,but my electric bike has helped improve my fitness,and helped me up hills that i would not have managed on a standard bike.

 

[flecc]

I think there's an inherent problem in e-bikes.

Most buyers are in older age groups and primarily want the hills to be made easy, but the only ways to do that are by drive through gear systems or very powerful hub motors.

I've covered the subject of drive through gears and it's numerous disadvantages in the Technical section here so won't go through all that again.

That leaves us with the powerful hub motor systems that cope with the hills, but as an accidental by product have excess power for flat riding, and therefore have motorcycle characteristics. And of course, they are nothing like as nice to ride without motor power as good normal bikes.

The Torq has the same without-power pedalling disadvantages but overcomes the excess power problem by having it's motor 40% overgeared from the legal speed requirements norm, but in consequence suffers hill climbing which is inadequate for most of the main customer group mentioned above.
.

 

[JohnInStockie]

The reality is that hub motors work extremely well and most offer negligible resistance when freewheeling.

Sorry, I was under the impression that some hub motors offer quite noticable resistance, or is that more relative to the rider and their fitness?

From all the evidence though, hubs are in fact an extremely successfull innovation for electric bicycle development.

But it does seem as of the electric bicycle is becoming something other than a power assisted bicycle however given the current desired characteristics of the electric bicycle versus a normal bicycle.

Does the assistance factor now look like 'Pedal Cycle -> Electric Bike -> Moped -> Motor-Bike' rather than classifying a pedal cycle and pedelec together (as I always had in my mind)?

John

 

[jac]

hi i think we need as many variations and drive systems as possible that way everyone should be able to get something to suit them. panasonic drive systems are used in various bikes also yamaha and the opti bike all use crank drive systems which are very reliable thats why gazelle can offer 2year warranty on all electrics on there bikes thats a warranty you dont see on many hub motor bikes

 

[flecc]

hi i think we need as many variations and drive systems as possible that way everyone should be able to get something to suit them. panasonic drive systems are used in various bikes also yamaha and the opti bike all use crank drive systems which are very reliable thats why gazelle can offer 2year warranty on all electrics on there bikes thats a warranty you dont see on many hub motor bikes

In fact hub motors are more reliable than the Panasonic system or other crank drive systems. Hub motors normally outlive the bikes they are fitted in, and there are always many of them on the second hand market for that reason.

In contrast, I know of many failed Panasonic drive through gear motor systems that were between two and six years old, made worse by there being no way of getting them repaired due to sealed in components and no spares available. The other problem with them is that they can also cause hub gear failure, since the gears have to cope with the double load of both the rider and the motor driving through them, which those gears were never designed to do. I'm sure those are the reasons why they've tended to disappear from the mass market, in favour of the simpler and more reliable hub motors.
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[jac]

we should be getting a much better deal on warranty than we are if that is the case also on an earlier posting we had someone riding a forza who could not get up a 10% hill without bike stopping after quarter of the way up this on one of most powerfull bikes around

 

[coops]

I recall that the Forza's stopping was most likely a combination of power supply from the lithium battery "cutting out" under heavy load (the 10% hill being a mile long ) plus a possible lack of sustained rider pedal contribution, quite understandable I'd say for anyone on a hill that long and steep, except perhaps professional cyclists , rather than the forza's motor lacking the power to climb the hill, which it does not, especially for a rider of the weight in that example - around 10.5 stone if I recall? .

I agree that more drive systems would be a good thing for bikes to be more suitable for all, but one in particular: the sooner someone implements Flecc's (patent pending ) motor gear system in hub motor manufacture, the better! I guess that's more "future designs" than "latest" designs though... unless anyone knows otherwise?

Its relevant to your questions though I think John, because such a "smarter" and (dare I say it...) more efficient supply of battery power to the motor would possibly allow relatively light and more moderately powerful motors e.g. Torq / quando standard motor, to be used to make ebikes rather more versatile on hills, with more power at low speed aswell as power geared for speed too, and all more energy-efficiently too than at present. That is, you'd have an ebike which hopefully still feels more like a bike than a motorbike, but would also be, in principle, more efficient and economical than they are now - especially if one stop-starts a lot, or if used much on steep hills.

I'd definitely strongly consider buying a bike with such a motor!

Stuart.

 

[flecc]

we should be getting a much better deal on warranty than we are if that is the case also on an earlier posting we had someone riding a forza who could not get up a 10% hill without bike stopping after quarter of the way up this on one of most powerfull bikes around

As coops said, that was the lithium battery rather than the bike. With the NiMh battery in there the Forza would climb very much steeper hills without any possibility of cutting out.

The trouble with taking any of these cases literally is we don't know any of the circumstances. If, for example, a 17 stone person tries to make an e-bike climb a steep hill without any pedal help, of course it will fail. Too many people forget that these are electric assist bikes, and the motor is only there to give a bit of help. It's not there to do the whole job, and it follows that this goes for the battery as well.

Those who want a motor vehicle should buy one, not unrealistically expect an e-bike to perform as one.
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[Ian]

One thing the vast majority of the latest designs feature is a lithium battery, often hyped as the latest technology, and yet time after time we read read posts from users complaining about cutting out and rapid deterioration of capacity. Isn't it time manufacturers acknowledged that this battery type is not well suited to the higher power bikes, any capacity/weight advantage the battery may start with is eroded after a few months of use. At least with the Ezee models there is the option to downgrade (although that should perhaps be read as upgrade) to a NiMh battery, an option not available on many other bikes.

 

[Jimblob]

also yamaha and the opti bike all use crank drive systems which are very reliable thats why gazelle can offer 2year warranty on all electrics on there bikes thats a warranty you dont see on many hub motor bikes

Actually, all Powacycle motors are backed with a 2 year warrantee, which we honour, and have hardly ever needed to take advantage of!

My experience with crank drive is, it's a real nightmare if/when it does need servicing and repair. Hub motors are undoubtedly the way.

Electric Bike Sales - Home

 

[jac]

the warranty on gazelle includes the battery also most people would assume if you buy the more expensive lithium battery you are buying the best of the two options not the worst there are some high quality lithium batteries out there they just happen to be more expensive as you can see when you look at the performance on the kilacycle

 

[Ian]

The gazelle is a relatively low power design so may be suited to a lithium battery. The cutting out and short life of of Lithium types has little to do with battery quality, short term chemical exhaustion under high load is simply a fact of life with lithium batteries as is short cycle life with repeated use of the full battery capacity. The only solution in both cases is specify a much larger battery than is actually required as is done to satisfy military and aerospace requirements (And in the kilacycle). The cost and weight penalty though excludes this solution from consumer products.

 

[Canadian Cadence]

With my limited use of hub motors I think the gearing on the bike is very important to help "assist" the motor when hill climbing. I have found that with my set up the choice of 24 different gear ratios and the rapid fire gear shifters will tame any hill with a very modest effort on my part. Changing the gears on a climb so that there is the assist to the hub motor keeps the motor in or around its power band and it crests hills at very good speeds.
I have also found there is very little drag with this motor (350 w Bionx brushless gearless motor) and find I use it on rides with other people in the unassisted mode (they do not have electrics) and the bike keeps up with them when coasting down hill!!
I really think the improvements in e bikes in the future will be with the bike it self ...lighter, gearing etc but still using the dependable hub motors. Of course a new 2kg battery that will get 200 miles per charge and is affordable would be a great breakthrough ....but ....

 

[flecc]

It's true that direct drive motors like the BionX have potentially the lowest drag, as they haven't got the orbital gearset of most hub motors that has to be driven by the wheel when unpowered. The snag with direct drive of course is the relative lack of low speed torque, which on the UK 250 watt limited versions of the BionX leaves it inadequate for our steeper hill areas. Likewise the direct drive Sparta Ion M gear.

In support of what Ian has said, Lithium batteries are only any good on low powered bikes up to around 350 watts peak gross power. The more powerful motors of around 450 watts or more gross draw more power on continuous load than current lithium batteries can deliver for more than a few minutes, the cathode chemical interface unable to cope.

Once all the bugs of iron based cathodes have been fixed, Lithium Iron (LiFePO4) batteries may solve this since iron is the best cathode material known for this application. Until then, all higher power bikes should come with NiMh batteries as standard, since at present they are not wholly fit for purpose.
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