Recommend a bike for touring

[flecc]

That result flies in the face of reason Leonardo, as your query implies.

The test could not have covered all degrees of hill climbing. The eZee hub motors are some of the most powerful, the Sprint peaking at 500 watts withg maximum torque at 8 to 9 mph. Obviously this means it will outrun a Swiss Flyer on the more gentle slopes, but conversely, on steeper hills where speed drops below 8 mph, the Flyer will be better.

As an example, I can climb a continuous 12% pulling a 14 kilo fat tyred trailer with minimal pedal assistance on my Twist with the Flyer type power unit. I know the Sprint couldn't do that without a huge input from me to keep it at 9 mph or more.

As you know, with the Flyer and Twist there's no need to keep up a minimum speed, we can just change down for hills in the manner we do with cars.

 

[Flying Kiwi]

Looking at the Extraenergy test results, I see that the Ezee Sprint “uphill factor” is rated at 5.3, while it is 2.8 for the Giant Twist and 2.1 for the Flyer T8. I’m not very sure about the methods they use

You're correct with your instincts that those uphill factors aren't a realistic comparison of those bikes suitability for hill climbing, particulary with steep hills. No legal hub motor powered electric bicycle is going to beat the ability to shift down and have the motor remain running at it's most efficient speed for hill climbing. Hub motor bikes may be easier to design and build for the manufacturer, and consequently sometimes cheaper but they just cannot offer the flexibility that comes from having the motor power transferred through the gear train.

 

[Leonardo]

Thank you Flecc, I didn't think at the speed matter. It explains all.
And thank you Flying Kiwi for confirming my impression. No really steep hills. I see now that they measured on the basis of the following "Mountain Track The 1/3 miles long route begins with an 8% incline and then decreases into a 7 % incline. Here, assistance factor and mountain range were measured."

 

[Tim]

I agree with Flying Kiwi regarding the Twist, I routinely ride mine for miles without switching on the power, even when towing a large trailer on the flat, but wouldn't dream of trying that with the Torq or any other electric bike I've tried.

I'd strongly advise you not to choose the Torq without a thorough hills trial first. The hub motor is geared 50% higher than other electrics, with maximum torque at 12 mph instead of about 8 mph on most hub motor bikes. That means if the hill is too steep to maintain 12 mph up it, the power drops off rapidly as the speed falls and you're left inceasingly on your own. But that's no good since you can't help then, as it's derailleur bottom gear is also very high at 58", which is a generally accepted middle gear on road bikes. Indeed, it's the middle gear on the 3 speed Twist. The Torq has no low gears at all.

50cycles can easily and inexpensively fit a range of gear options, including a Shimano single speed nexus chainset with a 38t ring on it which would give a very low gear ratio and coupled with a lower ratio 8 or 9sp cassette would be ideal for very hilly areas. The Torq is just too good to eliminate like that!

 

[Miles]

50cycles can easily and inexpensively fit a range of gear options, including a Shimano single speed nexus chainset with a 38t ring on it which would give a very low gear ratio and coupled with a lower ratio 8 or 9sp cassette would be ideal for very hilly areas. The Torq is just too good to eliminate like that!

So, just when you need the most help you're on your own, with the additional burden of the weight of the motor and batteries

 

[Flying Kiwi]

So, just when you need the most help you're on your own, with the additional burden of the weight of the motor and batteries

I agree! If the manufacturer really wanted to do the right thing, they'd take the time to design and offer a proper system, where the motor power goes through the gear train rather than the current compromise situation.

 

[flecc]

Sorry Tim, but as Miles posts, gearing down the bike further to allow for hill climbing doesn't help as the motor power diminishes rapidly as speed drops at anything below 12 mph, the point of maximum torque. Then you end up increasingly on your own with 24 kilos plus and fat tyres. It's little more effort to use an unassisted light bike, say 12 kilos, with slim low rolling resistance tyres, since that can be ridden up at the lower speeds without the weight and drag penalty.

Electric bikes are electric assist, and that demands the gearing of motor and rider gears are aligned. Creating a huge disparity between the two just doesn't work.

As I've pointed out before, there is no Torq motor as such, that motor in the Torq was designed for the Quando using a 20" wheel, and in that it's geared in agreement with virttually all hub motor bikes including all the other eZee models except the Torq, with maximum torque at about 8 to 9 mph. Experience has shown that this is the best compromise to enable both reasonable hill climbing with attainment of the legal speed.

The Heinzmann versions illustrate these points well. They can be in the standard gearing for the above performance, with lower gearing to give better hill climbing at the expense of speed, or with high gearing to give 19 mph at the expense of hill climbing.

With it's 28" wheel, the Torq is geared up by no less than 40% from it's Quando design specification, and that's very much at the expense of steep hill ability. The same motor cannot gain in both directions at once. After all, eZee give it's limitation as 1 in 10 hills, which is not terribly steep in this country.

I'm certainly not just writing off the Torq, I'm just presenting it's limitations, as it's not a universal bike and a less good choice for very hilly territory. In less demanding territory I think it's possibly the best electric bike in the world available at a sensible price, and for sheer fun it's unbeatable. But what I don't like to see is people buying it in the belief that it will make steep hills easy, because that is just not possible. The only way to avoid that happening is realism about both the facts and the bike's abilities.

Finally, VroomVroom is going touring, and bikes doing that often look like skinny pack mules with all the gear hung on them. All that extra weight requires lower gearing, and a motor geared up so much is the opposite of what's wanted to give assistance.

 

[flecc]

Tim

In less demanding territory I think it's possibly the best electric bike in the world available at a sensible price, and for sheer fun it's unbeatable.

To show no anti bias, I've extracted this quote from my own post, since I wish to add that I think the eZee bikes are far and away the most important electric bikes on the UK market. Against a tide of low powered hub motor bikes mainly only good for the Dutch market that are coming in now, eZee are the only up to the minute designs providing real power with their hub motors.
That's very welcome in the absence of new viable through chain drive bikes.

 

[VroomVroom]

Interesting discussion people, got a lot out of it, carry on. Cheers for the links 50cycles, everything helps.

So the Flyer and old Twist are on the list at the moment. I will test a secondhand old version Twist this weekend hopefully, just 740 euros and 500kms on it. With the money I would save I could get an extra Lithium-ion battery....or 2.

look like skinny pack mules with all the gear hung on them

Haha, nice one flecc.

 

[Leonardo]

500 kms seem me a very (too much?) little use… price is really attractive. You should have a look at flecc’s page to understand which model you’re buying (3 / 4 / 5 speeds). It is not a fast bike in my experience (but neither the Flyer T-series are, although more speeds and the bigger wheels help a little): try to understand how you feel without assistance in the high speed. Furthermore, since probably you’ll not be able to check the battery range, you should consider the possibility that you have to re-cell the battery and/or buy a new one (in that case be sure to buy the new 9ah battery, which has much more range than the old 6.5ah: check for price and availability in your country). The old Twist doesn’t use Lithium batteries; however its NiMh battery weights only 3.7 kgs (may be a bit more the 9ah one). Good luck!

 

[Flying Kiwi]

Over to battery type now

Interesting discussion people, got a lot out of it, carry on. Cheers for the links 50cycles, everything helps.

So the Flyer and old Twist are on the list at the moment. I will test a secondhand old version Twist this weekend hopefully, just 740 euros and 500kms on it. With the money I would save I could get an extra Lithium-ion battery....or 2.

I wonder why you specifically want Lithium-ion batteries? To make them fit the original style twist, there'd be quite a bit of redesign work involved including the need for a different charger. Whats wrong with the classic 24 Volt Nickel Metal Hydride batteries used (other than the giant price tag for additional original batteries)? You do realise although some manufacturers try to claim massive advantages of Lithium Ion over NiMH for marketing purposes, there are in fact distinct advantages to each type?

 

[flecc]

I'll second that Flying Kiwi, the more I use both types, the more I like NiMh, and the comparison is between both on each of two bikes.

The proven NiMh life of four years and still usable, but with reduced capacity, on the Twist batteries is not to be dismissed either.

 

[VroomVroom]

From what I read by users, they are lighter and you can do some more kms. Their overall lifespan seems lower but that doesn't outweigh the former advantages for me. It makes a huge difference when touring, even if it's let's say 1 kgs lighter and gives you only 5 kms more, it all adds up to the overall sum. And it seems the numbers are higher than that.

For your normal everyday use (commuting/etc), I'm sure it's not necessary.

 

[flecc]

Indeed they can give longer range as a result of capacity increase, and they are lighter. However, life is never that simple is it?

The range increase depends to some extent on terrain, since in high drain situations Li-ion batteries can suffer some chemical exhaustion after a while. Resting the battery can recover some of that loss, but it's not all recoverable, the greater the exhaustion, the greater the loss. The battery isn't damaged though, the loss is just journey based.

Another factor is the type of Li-ion. The cobalt based chemistry gives the largest capacity gain, as much as 40%, but has a reputation for instability that can lead to sudden failure and even fire. The manganese based chemistry is much safer but sacrifices much of the capacity gain, which is often only 10% more than NiMh. Since they also suffer the exhaustion I mentioned, the range in difficult terrain can be the same, and I even achieved a lower range from manganese Li-ion on one of my most difficult routes.

However, I mustn't give the impression that they are not worth considering. In average terrain they give a real range increase, and in easy conditions the increase can be very large.

 

[Flying Kiwi]

From what I read by users, they are lighter and you can do some more kms. Their overall lifespan seems lower but that doesn't outweigh the former advantages for me. It makes a huge difference when touring, even if it's let's say 1 kgs lighter and gives you only 5 kms more, it all adds up to the overall sum. And it seems the numbers are higher than that.

Those users haven't told you the whole story then. I get the impression that for marketing purposes Li Ion is being bandied about as the magic battery, it's not!

Did you see the news about Lithium laptop batteries catching fire on TV recently? Although I'm not aware of any electric bike batteries catching fire, Lithium Ion batteries as a whole are less "tried and tested" than Ni MH and they definitely require much more careful charging and power management to avoid damage or destruction. As a whole, they're less robust than NiMH. As well as the lifespan often being fewer cycles (dependant on how its discharged for both types), the cost is generally much higher.

For your normal everyday use (commuting/etc), I'm sure it's not necessary.

For commuting purposes, just as in your case, it will depend what values the rider assigns to each of the benifits and disadvantages of each type. The marketing people will be very keen to make Lithium Ion look the clear "high performance" option but the price is currently still very high and its very questionable whether they offer better value for electric cycle riders in terms of bang for buck. When the price comes much closer to NiMH and they're more tried and proven then things will be clearer.

 

[Miles]

In terms of "bang for buck" there's nothing to beat NiCd

 

[flecc]

Did you see the news about Lithium laptop batteries catching fire on TV recently? Although I'm not aware of any electric bike batteries catching fire, Lithium Ion batteries as a whole are less "tried and tested" than Ni MH and they definitely require much more careful charging and power management to avoid damage or destruction. As a whole, they're less robust than NiMH.

Apparently at least one did rather disastrously, when a cobalt based one burnt down a lady's house in Germany.

Not nice, getting attacked by one's bike.

 

[flecc]

In terms of "bang for buck" there's nothing to beat NiCd

Yup! And I love the way they can surrender everything they've got very quickly and without complications. For ultimate power it's a good way to go. Experienced Heinzmann didn't stick with them for so long for no reason.

 

[Leonardo]

There was an interesting article about the dangers of Lithium batteries on the French pedelec forum (a very good forum, indeed).

Best Lithium batteries are now with the Manganese Cathode – as the Ezee and the Flyer. Furthermore Flyer (Panasonic?) batteries are built in a quite strange way: 14 cells of 4 A and 3,72 V in two series of 7 cells, that in parallel give a battery pack of 26 V 8 A - every cell linked with its small cable to the circuit of control (and therefore loaded individually?)… On the Italian pedelec forum we opened one to try to understand something, but the only hypothesis till now is that that strange construction depends upon security reasons.



@VroomVroom: You should consider that the old Twist batteries are really light, a couple of them are easy to carry and give you a large range.

 

[Miles]

There's quite a good overview of Li-Ion batteries by Tony Castles, in the latest issue of AtoB