A possible issue with the Pro Connect 10 is that, being 10 gears, the chain would be narrower, and therefore more likely to break, given the high torque and strain from the Impulse 2 mid-motor.

 

However, 9 gears are probably sufficient for most people, and could be more robust.

Is a narrower chain necessarily weaker?

If the side plates and rivets are still the same size and thickness as a wider chain, I would think that the strength is the same.

It's a German brand-

Kalkhoffer?

Kalkhoffen?

 

das Kalkhoff for singular, die Kalkhoff for plural.

Is a narrower chain necessarily weaker?

If the side plates and rivets are still the same size and thickness as a wider chain, I would think that the strength is the same.

 

I am not a mechanical bike expect, but that's what I have read. Also, several people have reported breaking chains on a Pro Connect bike, which is not great, when you are out and miles from home.

 

I guess the combination of high number of gears/narrow chains, derailleur and high torque is straining the chains, and that's why Kalkhoff is moving to belts and hub gears on its most expensive bikes.

Although I rarely find any argument with your posts Tillson, I find that statement a little contentious. I have to think you are referring to front hub motors as rear motors and the pedaller do have the benefit of gears.....unless I'm missing something.

 

Tillson means the common hub motor hasn't selectable gears, so whether front or rear can't run at optimum efficiency at all road speeds. They are only at maximum efficiency at one road speed, usually about 80% of the maximum assist speed.

 

The rider's gears do not affect that.

 

Having said that, although crank motors drive through the bike gears, the gear a rider chooses for themselves will only occasionally match the motor's optimum efficiency, so they also have their weakness.

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Isn't there a third way? Efficiency. If a motor is running at its optimum efficiency, which it is more likely to be doing if driving the wheel through a set of gears, then the energy stored in the battery will be used more efficiently, hence greater range. A hub motor, of which most are stuck in one gear, can be horribly inefficient at certain speeds. It more or less becomes an electric fire when stalled.

one of my commutes is a hilly, fast (bad shoulderless b road) 27 miles, I do it regularly on a 13 ah 36v hub kitted bike - usually loaded with stuff (all up weight often around 95 kgs), hammering along at 20 to 24 mph. I get 30 miles out of the 13 ah battery. ive don eteh same journey on a tasman with impulse 2 of a friend, and got slightly less mileage out fo what iirc was an 11 a/h battery - so more or less identical efficiency in my real world experience. im not sure why - I can see the logic of what youre saying, but it doesn't translate into real world experience for me. maybe its because electric motors don't deliver torque in a curve (more or less same at low and high speed), maybe its because as flecc says human judgement goes awry and riders make crank drives run inefficiently. maybe its apples and pears: I do the commute faster on the hub drive than crank drive, but its a racer versus a sit up and beg. either way, in my life there isn't a lot in it.

I think this is the ongoing debate about hub driven pedelecs vs. mid-motor/crank driven ones.

 

From what I have seen so far, doing some market research before purchasing my bike, all premium/top of the range models seem to adopt a crank driven system (Bosch, Panasonic, Kalkhoff's own Impulse etc), whereas all the entry level ones are hub-driven.

 

Surely, this is an indication that crank-driven bikes must be better, either in term of assistance provided, or efficiency.

 

In term of efficiency, all crank-driven bikes need inputs from the rider, and therefore it's difficult to compare like for like.

 

From what I have tested, I much prefer a crank-driven bike, as it feels more like a bike with proportional assistance, as opposed to an electric moped with an independent motor from the chain. They also have the benefit of having standard mechanical bicycle components on most of the bike.

 

Of course, for people with more limited budget, or wanting to have a throttle and a lot of independent assistance, a hub-driven "bike" may be a better choice.

 

For cyclists looking for assistance (during climbs, or to increase their range), as opposed to a scooter, I think crank-driven bikes are a better fit.

I think this is the ongoing debate about hub driven pedelecs vs. mid-motor/crank driven ones.

 

From what I have seen so far, doing some market research before purchasing my bike, all premium/top of the range models seem to adopt a crank driven system (Bosch, Panasonic, Kalkhoff's own Impulse etc), whereas all the entry level ones are hub-driven.

 

Surely, this is an indication that crank-driven bikes must be better, either in term of assistance provided, or efficiency.

 

In term of efficiency, all crank-driven bikes need inputs from the rider, and therefore it's difficult to compare like for like.

 

From what I have tested, I much prefer a crank-driven bike, as it feels more like a bike with proportional assistance, as opposed to an electric moped with an independent motor from the chain.

 

Of course, for people with more limited budget, or wanting to have a throttle and a lot of independent assistance, a hub-driven "bike" may be a better choice.

 

For cyclists looking for assistance (during climbs, or to increase their range), as opposed to a scooter, I think crank-driven bikes are a better fit.

yes, if one believes marketing hype all of that is no doubt very true (and wearing Armani knickers and Lynx while driving a little BMW is also no doubt scientific symptoms of virility). It all depends on the hub drive itself: I have a 36V 15 ah that provides a gentle hill of torque that allows me to exercise within my optimal zone while travelling further rand not being entirely hammered when I get to work (but trust me I'm much fitter now than before I started commuting this way). I've built a 3kw bpm hub bike and even that isn't entirely the moped you'd imagine (one still gets a workout if one finds the right kind of challenging terrain). these posts can be very divisive - the only rational thing I recommend is that whoever reads this should try a few bikes for themselves to judge rather than go by parochial views here.

yes, if one believes marketing hype all of that is no doubt very true (and wearing Armani knickers and Lynx while driving a little BMW is also no doubt scientific symptoms of virility)

 

Well, if your argument is that a BMW/Audi is basically the same car as a Ford, then I guess there will be no convincing (usually from someone driving a Ford). There is surely a premium for the brand, but there are also some more objectives reasons to charge a higher price, in term of performance, build quality etc. There is also the depreciation/retained value, which means buying a more expensive German car is not necessarily a complete waste of money.

 

The Kalkhoff bikes for instance are more expensive than the Chinese ones, but then there is build quality, ongoing support/parts from the leading European manufacturer, associated warranty, lower depreciation etc, so not everything is down to the "badge" value/perception.

 

Clearly, the trend for all leading manufacturers is to move to crank driven systems. It does not mean there is no market for hub driven ones, but they are two very different propositions, and as you have advised, people should really test various bikes. If their budget is below £1,500, this would limit the number of options anyway.

 

I believe 99% of the Kalkhoff range is now crank-driven bikes, and there is no argument that Kalkhoff (or related brands from the same group) is the biggest manufacturer in Europe.

Well, if your argument is that a BMW/Audi is basically the same car as a Ford, then I guess there will be no convincing (usually from someone driving a Ford). There is surely a premium for the brand, but there are also some more objectives reasons to charge a higher price, in term of performance, build quality etc. There is also the depreciation/retained value, which means buying a more expensive German car is not necessarily a complete waste of money.

 

The Kalkhoff bikes for instance are more expensive than the Chinese ones, but then there is build quality, ongoing support/parts from the leading European manufacturer, associated warranty, lower depreciation etc, so not everything is down to the "badge" value/perception.

 

Clearly, the trend for all leading manufacturers is to move to crank driven systems. It does not mean there is no market for hub driven ones, but they are two very different propositions, and as you have advised, people should really test various bikes. If their budget is below £1,500, this would limit the number of options anyway.

 

I believe 99% of the Kalkhoff range is now crank-driven bikes, and there is no argument that Kalkhoff (or related brands from the same group) is the biggest manufacturer in Europe.

to some degree I agree with you - the geometry of the Tasman I tried was spot on, I like magura hydraulic hub brakes - I liked the bike in fact.

 

there's two things - one is - as you say - whoever reads this, don't make up you mind beforehand - try all the various designs you can (if you don't you may well end up with something that you "think" is right and then keep on justifying to yourself (and perhaps the world)must be right while missing out on a whole realm of other possibilities, some of which may well - and with pedelecs are in my experience - really really great). before i tried the hub drive i got i was absolutely convinced a 36v 15A hub drive would be "way too weak for my use".

 

the second is that im not at all sure about the quality part: I've had great support with my hub motor kit (controller replaced at no cost at the beginning technical advice etc all really quickly) and its been completely reliable (despite regular abuse). I've read about some other users very different nightmarish experiences here with kalkhoff and bosch. i can afford a tasman, i chose the hub kit by preference (it isn't all about money). quality also isn't all about money: e.g. in the long run IMHO a shimano hydraulic disc brake (say a £30 one from chainreaction)is, for example, far more durable than a magura hydraulic hub that costs three times as much - one has to judge stuff on their own functional merit

I think this is the ongoing debate about hub driven pedelecs vs. mid-motor/crank driven ones.

 

From what I have seen so far, doing some market research before purchasing my bike, all premium/top of the range models seem to adopt a crank driven system (Bosch, Panasonic, Kalkhoff's own Impulse etc), whereas all the entry level ones are hub-driven.

 

What sort of market research did you do? Of course if you only looked at premium bikes with crank motors, that's what you will find. Even your favourite manufacturer, Kalkhoffhave a range of bikes with hub-motors, or don't you consider Kalkhoff a premium brand.

Surely, this is an indication that crank-driven bikes must be better, either in term of assistance provided, or efficiency.

If you do your research wrong, you'll draw the wrong conclusions

In term of efficiency, all crank-driven bikes need inputs from the rider, and therefore it's difficult to compare like for like.

You can get crank-drive bikes with throttles. Loads of us have them. Time for a bit more research, maybe.

From what I have tested, I much prefer a crank-driven bike, as it feels more like a bike with proportional assistance, as opposed to an elecric moped.

You can get hub-motors with exactly the same control system and input as any crank-drive.

 

It seems to me that you're suffering from tunnel vision.

 

Also, in case you don't know, most people that have bikes with throttles rarely use the throttle. They nearly all have adjustable pedal assistance that they turn up and down just like you do. Adding an independent throttle to a bike doesn't have any effect on the way or the effort with which you pedal.

From what I have seen so far, doing some market research before purchasing my bike, all premium/top of the range models seem to adopt a crank driven system (Bosch, Panasonic, Kalkhoff's own Impulse etc), whereas all the entry level ones are hub-driven.

 

Surely, this is an indication that crank-driven bikes must be better, either in term of assistance provided, or efficiency.

 

It's no more than fashion and other irrelevances, the e-bike market has swung one way and the other several times over the years.

 

In the 1980s the early UK ones were crank drive, which then gave way to hub motors and other drives until 1999 when crank drives again took over the main market for a while. They then progressively lost out to hub motors and by 2006 the two remaining crank drives had been discontinued and hub motors ruled for a while across the whole market.

 

Then late 2007 second generation Panasonic crank units returned in two makes and the Kalkhoff e-bikes with them became good sellers. That was of course noticed in Germany and Japan and others started to jump on that crank unit bandwagon, first Daum, then Bosch, then Yamaha. Kalkhoff adopting Bosch as well meant that crank unit make gained from the Kallkhoff success in the market.

 

As the biggest seller, Kalkhoff saw the benefit of having their own crank unit, so adopted the earlier Daum design, modifying it to become the Impulse unit. And of course, China not to be left out now also make a choice of crank units.

 

So the current trend has more to do with "me too" than any considerations of what is best. Don't imagine it will necessarily last, as the history shows, the pendulum swings very easily.

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Edited June 19, 201510 yr by flecc

What sort of market research did you do?

 

I created an RFP document containing about 102 questions and issued it to the various manufacturers. I then created a balance scorecard with the responses (allocated scores). For the short listed vendors, I did some visits to their factories, and then tested their bikes in various conditions, including crash tests, stress tests etc.

 

It took me a long time. I guess thinking about it now, I should have just used a web search engine instead.

 

 

It seems to me that you're suffering from tunnel vision.

 

It seems to me that you are blessed with infinite wisdom. Unfortunately, not all of us are. I haven't seen many hub-driven bikes in the premium segment (e.g. > £2,000).

 

Hopefully, there is however some light at the end of the tunnel??

 

Also, in case you don't know, most people that have bikes with throttles rarely use the throttle.

 

What was your statistical method for getting to such conclusion? How many people were surveyed?

 

I apologise for calling a bike with a throttle an "electric moped".

Edited June 19, 201510 yr by Tomtomato

 

Then late 2007 second generation Panasonic crank units returned in two makes and the Kalkhoff e-bikes with them became good sellers.

.

 

So to summarise: the biggest manufacturer in Europe started selling a lot of crank-driven bikes and then developed its own system... So lots of people were purchasing bikes with crank drive: I guess there must be some reasons behind this...

 

Let me try an theory: maybe they liked the bikes?

...

I created an RFP document containing about 102 questions and issued it to the various manufacturers.

...

.

if you had sent woosh a questionaire, they apparently sell as many hub driven bikes as crank drive bikes.

 

What was your statistical method for getting to such conclusion?

It's not a statistical method. It's called logic. Why would anybody want to use the throttle when they can get the power automatically by pedalling, like you do? All bikes with throttles have a pedal assist system except a few DIY ones, where people don't understand how PAS works or can't be bothered with the extra work to fit one. Ask anybody on this forum how they use their throttle. You'll struggle to find anybody that uses it most of the time. We've discussed it and surveyed it on this forum several times. Also, I've looked after the test fleet of some OEM bikes at various shows. I never saw anybody only using the throttle except when I specifically asked them to so that they could see how it worked.

 

Do you think my statement about my use of throttles is wrong or are you just trying to score points in an argument? I pointed out your research as wrong because it is, and it's misleading for other people who read it and believe it.

The poster also has an upper second class degree from Oxford University but, like all other human beings, makes the odd grammar mistake now and then, despite being an insufferable stickler for correct grammar himself.

 

I share your view about how important this is, RobF. I'm mortified. If you could go over all my previous posts on here, all the copy on the 50cycles.com website and all my blog posts, making a list of all the grammar mistakes as you go, I would be genuinely grateful.

Tim, It's shame you didn't get the same education as D8veh, your grammar would have been perfect.....but you wouldn't be able to spell;)

if you had sent woosh a questionaire, they apparently sell as many hub driven bikes as crank drive bikes.

 

Yep, and why wouldn't they. Both systems have their advantages and disadvantages, and it's certainly not possible to state that one system is better than the other. It simply comes down to personal preference, and mine is for hub drive.

 

A possible issue with the Pro Connect 10 is that, being 10 gears, the chain would be narrower, and therefore more likely to break, given the high torque and strain from the Impulse 2 mid-motor.

 

You have edited out the comment that you made to being left stranded miles from anywhere with a snapped chain, but I really don't see why a ten speed chain would ever be likely to snap through normal use. I can't find any written evidence to back your claim up, but if as you say chains are snapping, then it would more than likely come down to poor quality original equipment, along with the possibility of poor gear selection.

I run ten speed chains, and mine probably have to put up with more arduous use in the space of just a few hundred miles, than most others are ever likely to put their chains through, after a life time of use.

Whilst I have worn chains out in mileage ranging anything from 100ish miles - 600miles, and cassettes and front sprockets in less than 600 miles, I have yet to have a chain snap.

It'll probably happen to me on the one day that I leave both my spare chain, chain tool, and spare snap links behind at home.

It's certainly no biggie if a chain did snap though, as it's just a couple of minutes work to replace a link, and I wouldn't be worrying about it.

The weak link for me, is the crank drive motor. The first bearing failure happened at roughly 600-650 miles, and the second bearing failure after a further 400 miles or so. By using your logic, that certainly doesn't make crank drive the better motor, and would make hub drive far superior.That damning and sweeping statement, would neither be correct or true.

Edited June 19, 201510 yr by EddiePJ

So to summarise: the biggest manufacturer in Europe started selling a lot of crank-driven bikes and then developed its own system... So lots of people were purchasing bikes with crank drive: I guess there must be some reasons behind this...

 

Let me try an theory: maybe they liked the bikes?

 

I prefer the theory that the Germans bought them because the e-bikes were German. Once Kalkhoff changed the crank unit from the Japanese Panasonic to the German Bosch one, the sales in Germany increased even more.

 

But The Netherlands population with the biggest e-bike sales in Europe stopped buying crank drives and now all their Dutch made e-bikes have hub motors.

 

Never discount nationalism.

.

.

three biggest advantages of hub drives are: low cost, light weight and independency from gear selection.

Three biggest advantages of crank drive are electrical efficiency, superior water proofing and better heat dispersal. CD motors have the copper wires on the outside and run at around 3000 rpm.

three biggest advantages of hub drives are: low cost, light weight and independency from gear selection.

I think independence from gear selection is a drawback in term of efficiency, and a positive for crank driven systems. In term of risk of having a chain snapping and not being able to go back home, then independence of the motor system from the bike mechanical drive train is a plus!

Edited June 22, 201510 yr by Tomtomato

 

You have edited out the comment that you made to being left stranded miles from anywhere with a snapped chain, but I really don't see why a ten speed chain would ever be likely to snap through normal use.

 

It didn't happen to me, but I have read it from two separate people, and at least one person had the original chain when it happened after 350 miles. Of course, we don't know the exact circumstances, whether the chain was well maintained, whether there was some early signs of likely failure being ignored like skipping gears, high amount of strain etc.

 

I am assuming that a 10 speed chain would be more fragile than a 9 speed one. How much more, I don't know.

 

I plan to change the chain on my Pro Connect 10 every 1000 miles proactively anyway (seems to be reasonable mileage), so hopefully will never happen to me.

 

Crank drive failure would indeed be annoying, but at least I assume the person would still be able to cycle home without motor/power. In term of warranty, I would expect a crank drive motor to last a very long time, and therefore still to be covered after many years, under SOGA, as it does not have to be serviced anyway, so user cannot be at fault.

No chain problems on my Bosch bikes.

 

That could change, although after several thousand miles I don't expect it to.

 

Chains are a consumable item and regular replacement must reduce the risk of a break.

 

Every 1,000 miles looks like overkill to me, it's not as if the chain is keeping a passenger jet in the air.

 

But I would never knock what could be called gold standard maintenance.

 

Every 1,000 miles looks like overkill to me, it's not as if the chain is keeping a passenger jet in the air.

Yes indeed, not that critical, although a chain snapping while going at speed can be quite dangerous, and also I wouldn't like being stuck too far from home (and I go much further away with my bike now).

 

How many miles do you keep yours?

 

I am cleaning, decreasing and then using dry lube (keeps the chain looking clean!) on mine regularly.

6300 miles on my Delite & still going strong without lubrication.

 

Oil only collects dirt & grit to cause wear, just keep it clean and allow the original chain lube to work, do not wash it out with oil.

6300 miles on my Delite & still going strong without lubrication.

 

Oil only collects dirt & grit to cause wear, just keep it clean and allow the original chain lube to work, do not wash it out with oil.

 

So I take you don't use a degreaser for cleaning then? Else you would surely have to oil/lube the chain!

 

Surely, not much of the original chain lube left after so many miles!