Sprocket wear

I ride with a mid-drive Bafang 750w kit. I have to replace the rear sprocket at least three times a year which gets expensive. Does anyone else have this problem?

How many miles per year, and how often is the chain replaced, and do you measure the chain elongation to judge when to change it?

 

The 750W if used at high power will be a big chunk of the cause.

 

I get 3,000 miles maximum out of a chain to 0.5-0.7% elongation, but that is a puny 250W 40Nm motor.

Thanks for your reply Matthew.

I do about 2000 miles a year on steep hills hence the 750w motor.

Proper e-bike chain and rear sprocket changed together three months ago, slipping already.

Using proper tool to check chain wear. It's OK.

I guess it's a cost I have to accept. I've thought about hardening a new sprocket. Not sure it will work though.

Is your front ring ok? And chain length, derailleur tension? I've no direct experience of higher power and its effects, but my front chain ring only lasts 3 chains worth of miles.

I ride with a mid-drive Bafang 750w kit. I have to replace the rear sprocket at least three times a year which gets expensive. Does anyone else have this problem?

All mid motor e-bikes with a chain drive will ALWAYS suffer more chain and sprocket wear, simply because all the motor AND the human developed torque travel via the relatively weak, chain drive.

Furthermore, certain failures of the mid motor unit on some designs, can also stop any torque from the motor or the rider, actually turning the rear wheel.

I call it "the single point of failure", which of course the mid motor brigade hate, because its 100% true, and for them, simply very annoying.

But any good engineer, taken as an average, will simply not buy a mid motor chain drive e-bike, just because they see and understand immediately, why this unfair strain on certain drive components, components originally designed for the level of torque that a human can produce, as being very obvious!

Of course there are also engineers that miss that problem completely, though I myself have yet to meet one!

And as someone else here, fully and correctly mentioned, the 750 Watt motor you have, just makes the chain drive wear problems even worse....a motor, assuming that you live in the UK, is of course totally illegal there. And as someone else here mentioned, apparently his 250 Watt motor, allows these components to have a longer life. If you are every stopped by the Police, or are involved in an accident, that motor may count against you legally.....

The chain component wear problems are only (very) simply physics, nothing more, nothing less.

So you either have to accept the wear effects as "running costs", or change to a hub motor system e-bike, where the torque of the motor actually tends to "reduce" the wear and tear to chain drive components, and they generally, provided they are of reasonable quality, which makes them last even longer than the same components on a traditional non e-bike system, due to the much lower torque being passed through these chain components, on a hub e-bike system.

A further problem with the "Single point of failure", is that if damage occurrs on the chain components, it will usually mean a walk home, or a pickup by a car, as the bike may not have any power drive, human or motor, to the rear wheel.

Whereas the hub e-bike owners, simply remove say the broken chain, get on the bike and simply do "air pedaling", to activate the motor, or simply twist the throttle, to drive home on any remaining battery power.

My first e-bike got me home with the "air pedaling", and the second can be got home with both "air pedaling" and/or "throttle", its a great system.

 

This same subject gets regularly addressed on Pedelec, with the mid motor e-bike owners, doing the job of being the "nay sayers", because they simply neither understand nor accept simple physics wear and tear, in a system that (in my opinion) was not properly designed for problem free long term riding.....!!

The mid motor owners, appear to be under the impression that as they paid many times the average price of most hub (because of far simpler hub drive mechanics = cheaper) e-bikes, that they bought something "BETTER"! But they really didn't, and they find this MOST galling.

They actually have bought something with many different possibly "built in" failures.....at a far higher cost. Not forgetting that some manufacturers actually install firmware that precludes an informed owner, from maintaining his own e-bike himself, like even replacing a battery,which I find totally appalling!

My second e-bike new, complete with two batteries, cost only a tad more than a replacement motor (may not even be new, just repaired!) for a Bosch e-bike, and where the owner is precluded from installing it himself, and if the guarantee is gone, even has to pay the bike shop to do the work, as well as the price of the motor, around 800 UK pounds plus work at an hourly rate!!!

 

I hope that you now have a far better understanding of "why", but if you have any further questions, please just ask us all here on Pedelec, as the massive amount of experience here, can help a fellow rider almost always.

regards

Andy

Edited November 26, 20223 yr by Andy-Mat

A friend bought a 250w hub drive ebike, it burnt out within a week. Tough hills here in north Wales. I've owned this 750w mid-drive for five years now, love it and would never change.

Andy-Mat has an obsession against mid-drive.

 

They certainly get through chains and sprockets more than hub drives. A 750w motor used on hard hills certainly will though, I can't judge if your wear is beyond even what to expect from that.

 

The chain is also a single point of failure as he says; but only one of many single points of failure in any bike, and easily fixed if you carry a chain tool. There may be other failure points in a badly designed mid-drive units, or ones that are overstressed. As there are in badly designed hub motors.

 

He's also right about Bosch and other proprietary systems, most of which (but not all) are mid-drive, but that doesn't apply to your Bafang.

 

The benefits of crank drive are huge where you have tough hills.

m8 has a bafang mid drive and getting the chain line right at the motor sprocket was a pita on the frame he had and had to make custom spacers to sort it out or it just eats the chains and cassette as uses a throttle and max amps.

A friend bought a 250w hub drive ebike, it burnt out within a week. Tough hills here in north Wales. I've owned this 750w mid-drive for five years now, love it and would never change.

I have had 2x 250 Watt rear hub e-bikes, they are the only legal ones here allowed.

The first bike was a cheapo, and I paid around 180 UK Pounds for it, 12 months old, and I covered around 30,000 Kms, over 8 years, riding in all weathers except snow and ice. I used 2 new chains and one new cassette, plus new tyres, tubes and brake blocks (Vee brakes) each year. I gave it away still running....It was still runnning over a year later (only one battery, correctly charged of course!), the last time I met the owner....

My second e-bike, also a rear hub, was brand new, I still have it, but I have not kept an accurate log of the distances covered, but I expect it to be about the same per year as the old one, and other than newt yres, tubes each year, and new brake pads about 2 to 3 times a year, nothing else has been needed.... I live in a very hilly part of Germany, about 25 miles north of Frankfurt, and I go "mountaineering" with my dog running beside me..... hard work for the motor and the brakes. It wears the dog out too!!

 

It sounds like your friend bought a crap bike if it only lasted a week, did he get his money back? I would have!!

 

The beauty for me about hub bikes is that the drive system, just by its nature, is more efficient and far simpler, therefore less power is wasted in the transmission system, as any qualified engineer will tell you, plus the motor is more open to the air, and far less likely to overheat, than a mid motor, and far, far less complex, and also less likely to have manufacturer's restrictive firmware.....

 

There are good and bad bikes around, both cheap and very expensive, as the old proverb says "You pays your money and you makes your choice!"

 

regards

Andy

The problem is chain alignment versus power delivery, the 750watt can eat a drive train in a couple of hundred miles set at 25 amps and high throttle use, or even snap chains

My cube conversion now has a 250watt bbs01 [previous bbs02 tweaked to the limit ] the drive train is calmer and lasts far longer all the harshness has gone under load 12 amps max and only 80 nm .Just needs oil and not constant replacement

I have had 2x 250 Watt rear hub e-bikes, they are the only legal ones here allowed.

The first bike was a cheapo, and I paid around 180 UK Pounds for it, 12 months old, and I covered around 30,000 Kms, over 8 years, riding in all weathers except snow and ice. I used 2 new chains and one new cassette, plus new tyres, tubes and brake blocks (Vee brakes) each year. I gave it away still running....It was still runnning over a year later (only one battery, correctly charged of course!), the last time I met the owner....

My second e-bike, also a rear hub, was brand new, I still have it, but I have not kept an accurate log of the distances covered, but I expect it to be about the same per year as the old one, and other than newt yres, tubes each year, and new brake pads about 2 to 3 times a year, nothing else has been needed.... I live in a very hilly part of Germany, about 25 miles north of Frankfurt, and I go "mountaineering" with my dog running beside me..... hard work for the motor and the brakes. It wears the dog out too!!

 

It sounds like your friend bought a crap bike if it only lasted a week, did he get his money back? I would have!!

 

The beauty for me about hub bikes is that the drive system, just by its nature, is more efficient and far simpler, therefore less power is wasted in the transmission system, as any qualified engineer will tell you, plus the motor is more open to the air, and far less likely to overheat, than a mid motor, and far, far less complex, and also less likely to have manufacturer's restrictive firmware.....

 

There are good and bad bikes around, both cheap and very expensive, as the old proverb says "You pays your money and you makes your choice!"

 

regards

Andy

My Haibike (mid drive, obviously) has done 6000 hard off road miles on 2 chains, 2 rear cassettes and original chain ring. I weigh 105kg and I am very hard on chains/sprockets

Your obsession against mid drive does not make sense at all.

Torque and its rapid inappropriate (mid gear) application kills chains and sprockets.(and poor maintenance as mentioned above) Modern pedelecs neither apply torque rapidly or at wrong time. The rider does. The torque produced by the most powerful ebike motor simply pales into insignificance at side of some heavy rider stood on a static crank pedal( or at mid gear change.) Perhaps you need to modify your gear changing strategy if your crank drive bike is destroying chains etc so prematurely.

I, ve tried hub drive (legal) ebikes and to be honest they simply can not compete with their mid drive legal counterparts. I actually found them bordering on useless for off road climbing.(and slow steep road ones)

Just completed 2000 miies on Giant Fathom e2..Original chain, chain ring, cassette and derailleur still fine.???

If crank drives are so poor in regards you mention why are they completely dominating the market, especially so in MTB. (I don't think top manufacturers are actually building any hub drive??)

Trek, Haibike, Giant, Turbo Levo, KTM, etc etc etc must all have got it wrong.

I, m afraid I strongly suspect anyone who chooses a hub drive has never actually ridden a crank drive. There really is no comparison on equal power motors, especially legal ones. . It really is a stark difference. One works fantastically, the other barely so. Go and hire a Haibike Flyon. You will never want another hub drive.

Edited November 26, 20223 yr by Zlatan

Andy-Mat has an obsession against mid-drive.

Actually, my obsession is designed more to inform people, particularly newbies, of the pros and cons of the different styles and designs of e-bikes. I learned via friends who bought Bosch bikes, around the time that I bought my first e-bike (2nd hand) of the awful problems some were having getting problems fixed by Bosch representatives.

For anyone who can read German, there are plenty of problems from these bikes still around on some websites here, hair raising at its best!!!...

So I just did a very quick search, and even if you don't read German, the titles make it obvious I feel, these are all Bosch problems, some VERY recent, you should get an idea of just how unhappy some customers are:-

https://www.google.com/search?client=firefox-b-d&q=German+Bosch+e-bike+probleme%3F

Apparently they do not expect Bosch motors to live much beyond 10,000 Kms, even today!! My first cheapo exceed that by a factor of three, just with my riding!

It was just good luck that I bought a hub, as a friend of mine wanted to get rid of one, and it appealed to me suddenly, and a test ride convinced me....and to an old Scot, the price was VERY appealing. :)

Plus, I simply did not even know of mid motor designs at that time (luckily for me!)

They certainly get through chains and sprockets more than hub drives. A 750w motor used on hard hills certainly will though, I can't judge if your wear is beyond even what to expect from that.

Ridden hard, I would guess that is simply par for the course, and has to be expected from both the illegal motor wattage, and the usage. Driven less hard would maybe reduce usage, but by how much?

The chain is also a single point of failure as he says; but only one of many single points of failure in any bike, and easily fixed if you carry a chain tool. There may be other failure points in a badly designed mid-drive units, or ones that are overstressed. As there are in badly designed hub motors.

A single point of failure on mid motors only, not on a hub. Reminder, losing the chain on a dark night, when its just starting to rain, is far less problemetic on a hub, as you get to ride home if you still have battery power....

Also I take my second battery if I am of the opinion that I may run out of power, and on my bike, as battery wap takes only 30 seconds to a minute at the most.

What other single point of failure are you talking about, between Hubs and Mids, I would be most interested to hear about them! from you, as all the ones I can think about, apply to BOTH styles of motor!!

He's also right about Bosch and other proprietary systems, most of which (but not all) are mid-drive, but that doesn't apply to your Bafang.

Sad problem, where some manufacturers feel its good to screw the customer base to make more money.

The benefits of crank drive are huge where you have tough hills.

Maybe you have only expereinced far less than perfect hub e-bikes (what makes and models please, to help our newbies to avoid them?), and I have been lucky with both of mine, but I have yet to see any difference with regard to my hub bikes compared to other riders and going up hill, and I am now 76 years old!

I switch down to the lowest gear and simply plug away, as I hate getting off and pushing! But one day it will start, I know......UGH!!

regards

Andy

My Haibike (mid drive, obviously) has done 6000 hard off road miles on 2 chains, 2 rear cassettes and original chain ring. I weigh 105kg and I am very hard on chains/sprockets

Your obsession against mid drive does not make sense at all.

Torque and its rapid inappropriate (mid gear) application kills chains and sprockets. Modern pedelecs neither apply torque rapidly or at wrong time. The rider does. The torque produced by most powerful ebike motor simply pales into insignificance at side of some heavy rider stood on a static crank pedal( or at mid gear change.) Perthaps you need to modify your gear changing strategy if your crank driver bike is destroying chains etc so prematurely.

I, ve tried hub drive (legal) ebikes and to be honest they simply can not compete with their mid drive legal counterparts. I actually found them bordering on useless for off road climbing.(and slow steep road ones)

Just completed 2000 miies on Giant Fathom e2..Original chain, chain ring, cassette and derailleur still fine.???

You are comparing a human, who in fine fettle can supply about 100 watts continuously, to a 750 watt motor? Where are you getting your facts from???

See here:-

https://www.npr.org/sections/13.7/2016/12/08/504790589/could-you-power-your-home-with-a-bike

Where you can read and hear (with no wind resistance!!!):-

Pedaling a bike at a reasonable pace generates about 100 watts of power. That's the same energy-per-time used by a 100-watt lightbulb.

If you doubled that for a fully fit bike racer, the facts still do not fit your thoughts!

If your aim is to put someone new off buying a hub bike, I can only say you need verifiable facts, not made up stories, with no meat in them!

Which is what I see each and hear every time from the people who bought a mid motor e-bike, and do not understand why it wrecks chain components, in comparison to simple hub motors..... To me personally its MOST obvious why, but not for everyone apparently, hence the obsession to inform people fully and accurately that I apparently have....

regards

Andy

bafang mid drives are the best as you can programme them parts are cheap and dont use fkn can bus but you want that power then it will wear parts at full amps and will hammer the batts capacity.

 

problem is like the diy ones that fit in the bb will fall to bits going down hill looks like a mess with all the wires on the outside but will only cost a grand for a hd motorkit and 17ah batt.

 

but even bafang is going can bus now which will mean no programming as want in on bosch bike prices and batts locked to there motors only.

 

but tbh if you gave me a bike with the new bosch smart motor on it that costs 15k to swap it for my bike no chance the only new bike id even look at is the yamaha motors that are still uart.

 

btw at full whack at 80-90rpm i can hit over 200w from my legs and in the kiox display is 20% of my input and 80% motor.

 

since 2014 if have only had 2 cassettes and about 6-7 chains as change at 0.5 seems to work for me but keep my bike super clean and will crash to avoid a puddle

 

but if you have a bosch bike peter can now do board repair if that can help anyone over there in Germany with shorted controllers.

 

Not many people know, but there are 73 different error code 500’s. What you can’t see on your handlebar display is the last three digits e.g. 500 111. Not that this would help as Bosch don’t tell you what these mean anyway.

 

The Ebike Motor Centre has teamed up with a local high-tech electronics company who had a team of engineers working with over 200 printed circuit boards, supplied by us, for over 3 weeks solid! Solving these software and hardware issues.

 

We can currently boast a 90% success rate of repairing all code 500 errors. This means it is no longer necessary to buy a new motor when it can be repaired. For the 10% that sadly can’t be repaired, we can usually offer a service exchange motor to keep you going.

 

https://www.ebikemotorcentre.com/

The contents of my tool and spares kit are strongly influenced by 'single point of failure analysis' and has gradually grown from pump, puncture kit and tube to include gear cable, chain quicklink, chain tool and spare wheel sensor pickup.

 

Always had a bike shop close enough to bail me out when something I hadn't thought of broke, so far!

Andy always seems to make his arguments in a combative style.

 

There are pros and cons to both systems. I own both, and really like both and appreciate their different attributes.

 

The can bus systems built into mostly the purpose built crank drive bikes serve nobody else but the manufacturer and are a right pita. They are effecting a lot of goods now.

 

I spoke to a mechanic of a very large crank drive selling bike shop recently and he said that the latest crank drive motors are built for performance and have got lighter and more powerful as a result. In his words they are brilliant to ride but not designed for a commuting role. This was born out when I chatted to Peter at Performance line bearings who told me the bearings on my 2015 Yamaha motor were much more robust than the latest motors. To make the motors lighter the bearings are now less robust than they were and the motors put out more power. If you are competent enough to take full advantage of their performance a high spec full suspension crank drive bike will offer an exhilarating ride. However like any high spec performance machine you need to understand the cost of maintaining such a bike and how long it will last.

 

I think that the problem is that crank drive bikes are now dominating the market place and someone new to electric bikes without a great deal of knowledge may buy one for a role that a simple geared hub motor bike would be more suitable, cheaper to buy, much cheaper to run, and much cheaper to keep running.

 

I don,t clean the drive trains of any of my bikes as often as I should. However I keep my chains oiled and keep an eye on chain wear and like soundwave tend to change chains around .5 wear point.

 

Interestingly, since I started measuring the wear of the chains on my bikes, I have found that although my geared rear hub bikes do take longer to reach this wear point than my crank drive bike, they reach it quicker than I had realised before I started measuring. I think before I measured the wear rate I just kept riding my bikes and the rear hub bikes can be ridden for thousands of miles further and sometimes years longer with a worn chain that a crank drive bike.

 

The Cassette on my crank drive Yamaha ridden mostly off road has completed 2,393 miles, 3,851km . I have swapped chains at wear limits but as my rear cassette must be getting pretty worn now have put back on a chain I previously took off when it just hit the .5 wear limit and will ride that chain until it is completely worn out. I expect it to get me through the winter. Then with the beginning of nicer weather I will put a new transmission on. This will involve a deep clean of the rear derailleur and replacement of the jockey wheels as well as a new chain, cassette and chain ring.

 

I like all my bikes to earn their keep but am not fastidious about their appearance. Change the brake pads, oil and change the chains at wear points, and change the tyres.

 

My Haibike Yamaha that I bought new in March 2015 for £1,750 is seven years old and has completed 16,732 miles.

 

My Befang rear hub Oxygen Emate that I bought new in June 2011 for £1,399 is eleven years old. The mileage is not recorded on that bike but it will be a lot as it gets used a lot. It did 6,000 miles by the end of its second year.

 

Note that my Haibike Yamaha was £350 more than my Oxygen which I thought good as it had hydraulic disc brakes rather than mechanical, 9 gears rather than 7, and an air adjustable front fork, all of which are really useful for serious off road riding.

 

My Yamaha crank drive is an infinitely better climber than my geared rear hub bikes. The rear hubs climb well up to a point, but beyond a certain gradient will bog down and drop out of their efficient power range.

Edited November 28, 20223 yr by georgehenry

However rather than immediately change the cassette I have added some miles and always found the grumbling cogs to settle down after 50 to 100 miles and get better each ride you do. The new chain kind of bedding in with the part worn cassette despite the previous chain being changed inside the wear limit.

 

[mention=12457]georgehenry[/mention] - You are absolutely correct, thanks for the tip - it took about 72 miles for my new chain to wear into the old cassette, which saved my buying a new cassette.

It has always been said on this forum a hub bike is far superior in reliability for any riding bar sport mtb riding, they are in the whole pretty bullet proof.

 

It is brands , brand sellers and a verciferous few with very deep pockets who poo poo hub bikes. It's like buying a ferrari or maserati to use as a shopping car .

Edited November 27, 20223 yr by Nealh

The contents of my tool and spares kit are strongly influenced by 'single point of failure analysis' and has gradually grown from pump, puncture kit and tube to include gear cable, chain quicklink, chain tool and spare wheel sensor pickup.

 

Always had a bike shop close enough to bail me out when something I hadn't thought of broke, so far!

Thanks for the reply (assuming that you are replying to my question of course), but none of these are specific to a hub bike, as I asked. In fact they are applicable to any bike, electric or not, except the last one......

The very specific "single point of failure" I tend to mention, to fully inform e-bike newbies, on mid motor e-bikes with chain drive systems, is, as far as I can see, specific only to mid motor chain drive systems.....

Though there are a couple of mid motor systems with drive shafts, but tend to be even more expensive than the usual chain drive mid motor bikes......sadly!!!

If an e-bike company managed to produce a drive shaft version, priced below that of the chain drive mid motor systems, and kept nasty firmware away from the design, they really do have the chance to make some big money.....and have happy customers.

With the present mid motor designs with chains, due to the way the torque is transmitted to the rear wheel, I do not see much of a possible improvement in wear characteristic, in the forseeable future.

Now that statement will really get the mid motor "fans" up and shouting again, because they don't want it to be true. But physics, as einstein would say, rarely change as we might wish them to!

A possible "kwik-fix", might be with really heavy duty chains, running on fully hardened sprockets, all at least twice as wide as the present versions, plus instensive cleaning and lubrication as least once a month, or possibly an old fashioned, fully enclosed, chain guard, to prevent dust/mud/water getting on the chain. My first bike had one a great many years ago!!

https://picclick.co.uk/Vintage-Rudge-Raleigh-26%E2%80%9D-Wheel%C2%A0-Oil-Bath-Bicycle-125439872240.html

Or:-

https://thecabe.com/forum/threads/enclosed-chain-guard-removal.132552/

A modern design, in a lightweight material, might reduce the need for chain cleaning and re-lubing!

regards

Andy

It has always been siad on this forum a hub bike is far sueperior in reliability for any riding bar sport mtb riding, they are in the whole pretty bullet proof.

 

It is brands , brand sellers and a verciferous few with very deep pockets who poo poo hub bikes. It's like buying a ferrari or maserati to use as a shopping car .

How true!

regards

Andy

https://electricbikeaction.com/bike-review-swind-eb-01-all-mountain-bike/

 

I agree Nealh. My Haibike Yamaha was the cheapest entry level bike that Haibike offered back in 2015. There were other Haibikes using the same motor system that were a magnitude of thousands more, probably as much as four times more expensive for the top of the range full suspension Haibike using exactly the same motor but with a much higher level of specification in relation to the parts fitted.

 

I bought mine to commute on and had no idea at the time that the Yamaha motor was more robust in terms of its bearings than the Bosch and inherently more suitable for commuting . I was lucky to choose it.

 

However its ability off road meant that I could ride much more demanding and technical routes to work having great fun within the capabilities of the bike rather than hammer my Emate on tracks it just was not designed to cope with.

 

The trouble was that at the end of a late shift I wanted to get home as fast as possible riding late at night on the road using a 10 mile B road route. The transmission of The Haibike was dirty from the cross country ride to work, and then the power of both me and the motor at first wreaked havoc with the 11 tooth top gear sprocket causing it to wear out prematurely.

 

I eventually found a simple way to extend the life of The Haibike transmission on the road route home by simply increasing the gearing with a larger chain ring and using a different but cheap 9 speed cassette with a 12 tooth top gear and a 14 tooth gear 8. I learnt only to use the lowest assist level when using the top gear. My bike could assist above the legal limit. Using the same road route each time I learnt exactly what assist levels were required for each section. Impressively the bike could complete the 10 mile journey in 30 minutes. I raised my gearing to the highest point that my bottom 36 tooth sprocket could still get me up the steepest most technical hill on my off road routes into work. I bought my bike in March 2015 and used it until I retired in October 2021.

 

After retiring I no longer needed that higher gearing or ability to hold cruising speeds on or slightly above 20 mph and simply put a smaller chain ring back on.

 

Before I bought The Haibike I had already been commuting to work for two years on my rear hub Oxygen, but had begun to experiment with an off road route to work and found that although the Oxygen was much more capable off road than I had expected I was still limited to the easier tracks, the advent of crank drive bikes and their ability off road made me want to get one.

 

At the beginning I was a boy with a new toy and used The Haibike for all my shifts at work including the early ones when I would ride both to work and back on the road. This just led to me wearing out transmission parts.

 

When I thought it through I came up with the best way for me to commute to work and back. On any shift that I needed to ride on the road both ways I used one of my rear hub bikes, which were better suited to commuting on the road and nicer to ride in that environment.

 

On any shift where there was time and daylight to ride on my off road route I used The Haibike.

 

That became a perfect compromise until I retired. Both styles of bike are brilliant, but it was best to use the bike best suited to the task. Once I started doing this the transmission on my Haibike lasted longer as my 14/16 mile off road route was ridden at a slower speed using the lowest assist level or no assist and generally in gears 1 to 7 rather than the more vulnerable top two gears. As I only used The Haibike when I could use the cross country route to work it was proportionately used much less on the road where the constant higher speeds caused the premature wear to my top two gears.

 

Andy makes very good points which I mostly agree with but just like life it is not quite as simple as he makes out and there can be very good reasons to favour a crank drive over a rear hub. If you can, have the best of both worlds like me.

Edited November 28, 20223 yr by georgehenry

I agree Andy that it would be quite simple to provide a heavier duty chain, chain ring and rear cassette design with perhaps as few as seven widely spaced gears.

 

After all motor bike chains hardly ever break and suffer the same single point of failure potential that you highlight.

 

For applications where reliability and longevity are more important than saving weight or outright performance, a so designed crank drive commuter bike or adventure bike would you have thought be highly appealing to many people.

 

The closest to this I have seen is the extremely expensive Rohloff rear hub gearing system paired with either a chain or a belt.

 

It does not need to be that complicated, either a derailleur system properly designed to cope with the power of crank drive motors or a similar hub gear system.

 

But then it would last a very long time with minimal maintenance and manufacturers don't want that!

Edited November 27, 20223 yr by georgehenry

Thanks for the reply (assuming that you are replying to my question of course), but none of these are specific to a hub bike, as I asked. In fact they are applicable to any bike, electric or not, except the last one......

The very specific "single point of failure" I tend to mention, to fully inform e-bike newbies, on mid motor e-bikes with chain drive systems, is, as far as I can see, specific only to mid motor chain drive systems.....

Though there are a couple of mid motor systems with drive shafts, but tend to be even more expensive than the usual chain drive mid motor bikes......sadly!!!

If an e-bike company managed to produce a drive shaft version, priced below that of the chain drive mid motor systems, and kept nasty firmware away from the design, they really do have the chance to make some big money.....and have happy customers.

With the present mid motor designs with chains, due to the way the torque is transmitted to the rear wheel, I do not see much of a possible improvement in wear characteristic, in the forseeable future.

Now that statement will really get the mid motor "fans" up and shouting again, because they don't want it to be true. But physics, as einstein would say, rarely change as we might wish them to!

A possible "kwik-fix", might be with really heavy duty chains, running on fully hardened sprockets, all at least twice as wide as the present versions, plus instensive cleaning and lubrication as least once a month, or possibly an old fashioned, fully enclosed, chain guard, to prevent dust/mud/water getting on the chain. My first bike had one a great many years ago!!

https://picclick.co.uk/Vintage-Rudge-Raleigh-26%E2%80%9D-Wheel%C2%A0-Oil-Bath-Bicycle-125439872240.html

Or:-

https://thecabe.com/forum/threads/enclosed-chain-guard-removal.132552/

A modern design, in a lightweight material, might reduce the need for chain cleaning and re-lubing!

regards

Andy

I have probably been quite fortunate, as my two most impairing failures happened one within reach of a bike shop, and the other during a work week on my 4km commute, so neither hurt me greatly.

 

Any failure I can cure on the road is for me no longer a problem, as long as my spares and tools are lighter than a cup of tea and smaller than a good pasty.

 

As for 'the big one', I recently found a barely used spare motor for my Shimano e5000 for under £200, the original sounds and rides no different to new after 8,500 miles, so not needed for quite some time, but won't be a big deal when it is.

 

I've no objection at all to hub motors, I just don't see my particular riding and area as compatible with them. I see gradients of MTB severity every time I go out, so mid-drive and low gears is the right horse for my course.

 

I have a winter project to fit 11 speed to my modest bike and have a go at Bealach na Ba with 38T front 50T rear, which I did not dare attempt with 36T rear in the summer! That's the kind of thing I want to wind my way up slowly and easily, not leave for another day.

Andy always seems to make his arguments in a combative style.

Its what I am as I have always stood up for myself and for anyone weaker, at all times in my 76 year old life. Its how others treat me, other people with no intelligence and no basic good manners.

 

Also seen far too often here on pedelec.....

 

But I have always allowed people who look for a physical fight with me, to have the first punch, not that it did them any good, as my Father, an electrical Engineer, started teaching me boxing when I first started school at age 5, as some other badly brought up little pig, punched me on my first day at school in passing, with no conversation! Just a thump in the stomache....a cowards blow in my book, as we had never even met till he hit me!!!

 

It was a revelation Iabout bad people that I have never ever forgotten.

 

Dad afterwards taught me well, as he was a school boxing champion in his youth, he was the one who trained me to never hit anyone first, but I never fought in a ring, as I have a so called "glass nose", which bleeds at the tiniest provocation, and looks far worse than it really is!! I did discover that Bleeding on an opponent, when you are sitting on him and he's getting a red shower, usually stops most school time fights!!

 

Not Navy ones though!!

 

Two years later the same little pig picked on me again, and got taken to hospital after about 30 seconds, with a badly damaged nose (that was never right afterwards...), again I allowed him the first punch, but I still got a telling off till I mentioned my first day experience, and he also later admitted it.

 

A dumb school bully, I still remember his name, Les Cope!!

 

Its important to remember, that all bullies are dumb (Trump?), as they cannot win verbal fights!

 

Its the socalled "Dunning Kruger effect"! The Dunning–Kruger effect is a cognitive bias whereby people with low ability, expertise, or experience regarding a certain type of task or area of knowledge tend to overestimate their ability or knowledge. Wikipedia

Trump is used as an example, by a US University Professor, David Dunning, teaching the "Dunning-Kruger effect" to Psychology students!

See here:-

You may like this one too:-

and this:-

 

In the Royal Navy (1963 to 1973), there are occasional fist fights (sad to say!), around one a year for me, of which I can honestly say, I never lost one, but several times I was (correctly) pulled off someone who was being half murdered (red mist?), but they then tried to get in a punch or two on me as I was being held back and unable to dodge! Now Navy Guys don't like that and I was immediately freed to finish my aggressive attacker as I saw fit.

 

I was never charged with fighting!

 

But I always gave them the first punch, as I never ever punched anyone first! Navy rules and regs that whoever starts a fight will get the full blame....NOT ME!!

 

My last really serious fight, was many years ago, in my own dining room, when a girlfriend of my first wife, brought her drunken boyfriend to our party, who challenged me to go outside IMMEDIATELY (village idiot), who was so drunk he could hardly stand up, but had muscles on places where most people did not, except for his very thin legs! I dodged his first attempt at a hit (I was still sober) and he got the "shoe in the face" treatment, street fighting as learned in Trinidad and similar places, as I could imagine that he was far stronger than me in the upper body.

 

He had very long hair, I always have very short hair even as a boy (today about 6mm, my COVID CUT!), as long hair puts you at a huge disadvantage in any sort of a fight, as he found out!

He actually apologised to me (suddenly sober) when the Police arrived (called by my ex wife, the Police wanted to cart him off!), and the next day he was all the colours of the rainbow!! I sometimes wonder if he ever found out why.......he was SO drunk, he may have thought that I used my fists!!!

 

A subject that I have as good as forgotten today, only an old man's memories......So sorry to take up so much of your e-bike time on Pedelec.....

 

I liked the rest of your comments below, they showed good common sense....

There are pros and cons to both systems. I own both, and really like both and appreciate their different attributes.

 

The can bus systems built into mostly the purpose built crank drive bikes serve nobody else but the manufacturer and are a right pita. They are effecting a lot of goods now.

 

I spoke to a mechanic of a very large crank drive selling bike shop recently and he said that the latest crank drive motors are built for performance and have got lighter and more powerful as a result. In his words they are brilliant to ride but not designed for a commuting role. This was born out when I chatted to Peter at Performance line bearings who told me the bearings on my 2015 Yamaha motor were much more robust than the latest motors. To make the motors lighter the bearings are now less robust than they were and the motors put out more power. If you are competent enough to take full advantage of their performance a high spec full suspension crank drive bike will offer an exhilarating ride. However like any high spec performance machine you need to understand the cost of maintaining such a bike and how long it will last.

 

I think that the problem is that crank drive bikes are now dominating the market place and someone new to electric bikes without a great deal of knowledge may buy one for a role that a simple geared hub motor bike would be more suitable, cheaper to buy, much cheaper to run, and much cheaper to keep running.

 

I don,t clean the drive trains of any of my bikes as often as I should. However I keep my chains oiled and keep an eye on chain wear and like soundwave tend to change chains around .5 wear point.

 

Interestingly, since I started measuring the wear of the chains on my bikes, I have found that although my geared rear hub bikes do take longer to reach this wear point than my crank drive bike, they reach it quicker than I had realised before I started measuring. I think before I measured the wear rate I just kept riding my bikes and the rear hub bikes can be ridden for thousands of miles further and sometimes years longer with a worn chain that a crank drive bike.

 

The Cassette on my crank drive Yamaha ridden mostly off road has completed 2,393 miles, 3,851km . I have swapped chains at wear limits but as my rear cassette must be getting pretty worn now have put back on a chain I previously took off when it just hit the .5 wear limit and will ride that chain until it is completely worn out. I expect it to get me through the winter. Then with the beginning of nicer weather I will put a new transmission on. This will involve a deep clean of the rear derailleur and replacement of the jockey wheels as well as a new chain, cassette and chain ring.

 

I like all my bikes to earn their keep but am not fastidious about their appearance. Change the brake pads, oil and change the chains at wear points, and change the tyres.

 

My Haibike Yamaha that I bought new in March 2015 for £1,750 is seven years old and has completed 16,732 miles.

 

My Befang rear hub Oxygen Emate that I bought new in June 2011 for £1,399 is eleven years old. The mileage is not recorded on that bike but it will be a lot as it gets used a lot. It did 6,000 miles by the end of its second year.

 

Note that my Haibike Yamaha was £350 more than my Oxygen which I thought good as it had hydraulic disc brakes rather than mechanical, 9 gears rather than 7, and an air adjustable front fork, all of which are really essential for serious off road riding.

 

My Yamaha crank drive is an infinitely better climber than my geared rear hub bikes. The rear hubs climb well up to a point, but beyond a certain gradient will bog down and drop out of their efficient power range.