Mid drive ?

[Mike TowpathTraveler]

Bike: 2016 model year Haibike Full FatSix. Commissioned in April, 2017. Yamaha PW drive. FSA front double chain ring. Shimano HG chain. 10 speed Shimano Rear Cassette.

Current miles on odometer: Approx 12,200. At around 11,000 miles, I finally stretched the chain beyond it's usable limits to the point where in starting to pedal, the chain would skip right off the front chain ring from the excessive slack.

I pedal in mainly water level riding, just local steep gradients coming out of a creek shed.

I religously keep the chain clean and lubricated with DuPont Chain Saver Spray Lube. How religious? Every other ride.

I pedal "lightly", shifting all the time to stay in or around 78 rpm. I do not "mash the pedals", instead.....I shift gears. Lots and lots of times on each ride. Prior to each shift, I ease up pressure on the pedals to avoid shock loading the chain, motor, chain ring, cassette. The Yamaha does NOT have shift detection like the Bosch does. YOU are the shift detection. OR....maybe you are not the shift detection!

TLDR.....but I wanted to set that all up to say that no matter how religous you are in lubing the chain, lightly spinning the pedals and the rest that sooner or later, wear is wear is wear. And so it was when my chain finally became unrideable. I figured if I'm gonna replace the chain, well, the front chain ring was shot too and since I was doing the front chain ring, chain too, that I'd treat the Full FatSix to a new rear cassette and rear derailleur too......

The below is what a new front chain ring looks like as compared to a worn chain ring at 11 thousand miles......

I hope this info is of help to you and other people as well. With all of this accumulated wear, mid-drives are still the best way to go, imo.

 

[jangles]

All three of my mid drives have a throttle and all three of them peddle easier than the two hub motored bikes we have . It's a no brainer . I thought I should add a picture since almost everyone else seems to have the need ! lol

 

[teskow]

I am confused about the hub drives/mid drives and why some saying they feel like being pushed by a hub drive. It seemed to me that other than a front wheel drive the power to the road is through the rear wheel/tire which is pushing the machine. How the power gets to the rear wheel I would think seems irrelevant to feel. Now weight distribution is another thing.

 

[Stefan Mikes]

I am confused about the hub drives/mid drives and why some saying they feel like being pushed by a hub drive. It seemed to me that other than a front wheel drive the power to the road is through the rear wheel/tire which is pushing the machine. How the power gets to the rear wheel I would think seems irrelevant to feel. Now weight distribution is another thing.

It is because the hub-drive motor acts on the rear wheel directly and independently of the rider's pedalling effort. To make it clear, fancy such kind of e-bike with a powerful motor and the throttle: The rider may stop pedalling completely and just apply the throttle: the bike is pushed by the motor. With the PAS system on a hub-drive, it is enough the cyclist is just pedalling because the very act of pedalling there is just another form of opening the throttle. (The cyclist can pedal lightly or strongly but it doesn't take any effect on the motor operation).

With the mid-drive motor e-bike, the amount of motor assistance depends directly on the rider's power input (which depends on how strongly pedals are pushed and how fast the cranks are spun by the rider = torque and cadence sensors are responsible for that). The combined rider's and motor's power is transmitted by the drive-train to the rear-wheel, and that combined torque is either multiplied by the drive-train for climbing or divided for fast riding.

These two systems are fundamentally different as to how the power is being distributed. Riding the hub-drive e-bike means "Oh, I'm always riding with the wind!" while riding the mid-motor one is like "Oh, I am a cycling superhero!" It is necessary to ride both types of e-bikes to really experience completely different feel of these two e-bike concepts.

To ride mid-drive motor e-bike slowly is easy: just downshift, pedal lightly and slowly. With hub-drive motor, riding slowly is impossible unless the rider throttles the motor back...

 

[FlatSix911]

Bike: 2016 model year Haibike Full FatSix. Commissioned in April, 2017. Yamaha PW drive. FSA front double chain ring. Shimano HG chain. 10 speed Shimano Rear Cassette.

Current miles on odometer: Approx 12,200. At around 11,000 miles, I finally stretched the chain beyond it's usable limits to the point where in starting to pedal, the chain would skip right off the front chain ring from the excessive slack.

I pedal in mainly water level riding, just local steep gradients coming out of a creek shed.

I religously keep the chain clean and lubricated with DuPont Chain Saver Spray Lube. How religious? Every other ride.

I pedal "lightly", shifting all the time to stay in or around 78 rpm. I do not "mash the pedals", instead.....I shift gears. Lots and lots of times on each ride. Prior to each shift, I ease up pressure on the pedals to avoid shock loading the chain, motor, chain ring, cassette. The Yamaha does NOT have shift detection like the Bosch does. YOU are the shift detection. OR....maybe you are not the shift detection!

TLDR.....but I wanted to set that all up to say that no matter how religous you are in lubing the chain, lightly spinning the pedals and the rest that sooner or later, wear is wear is wear. And so it was when my chain finally became unrideable. I figured if I'm gonna replace the chain, well, the front chain ring was shot too and since I was doing the front chain ring, chain too, that I'd treat the Full FatSix to a new rear cassette and rear derailleur too......

The below is what a new front chain ring looks like as compared to a worn chain ring at 11 thousand miles......

View attachment 75992


I hope this info is of help to you and other people as well. With all of this accumulated wear, mid-drives are still the best way to go, imo.

Thanks for sharing the front chainring photo... it clearly shows the meaning of the shark tooth wear pattern!

 

[Stefan Mikes]

Thanks for sharing the front chainring photo... it clearly shows the meaning of the shark tooth wear pattern!

Perhaps because Mike's been waiting for eleven thousand miles to replace the chain?

 

[Johnny]

Which bikes do you have in mind ?
Not every hub is the same, you can not generalize it. You can find lot's of discussions on the forums.
Also what grades are you going to be climbing ?
In terms of chain wear, mid drives will wear out chains faster than regular bikes because all the power is going through the chains.

 

[Stefan Mikes]

Is the chain just like an old fashioned bike? to me slipping a master link and threading new chain is a cinch anyway.

Oh, I missed that question from the OP. Yes, the chain for mid-drive motor (MDM) e-bikes is basically the same as for a traditional or a hub-drive motor. There might be some differences because the technology has made a great lap meanwhile:

• While traditional chain can be used for cassettes up to 8-speed, MDM e-bikes rarely come with more than 1 chainring. To compensate for that, so called "1x drivetrain" cassettes come in 9, 10, 11 or 12-speed versions. As the number of the cogs in the cassette increases as narrower the chain has to be. Therefore, a 10-speed cassette requires the "10-speed" chain and so on.
• Modern chains are directional and need to be placed in the correct orientation.
• To avoid chain dropping from the chainring, modern chainrings are designed in "Narrow-Wide" pattern. Meaning, the chain needs to be placed on the chainring according to a diagram.
• Typical MDM e-bike requires a longer chain (more links) than a trad bike. For that reason, chains as long as even 138 links are available.
• To add more complexity, some chain manufacturers provide specific master links for the chains but some advanced chains only come with a pin, so joining the chain might require a proper chain tool (for instance, the 12-speed chain requires the "12-speed" chain tool).

Because of marketing reasons, some manufacturers make expensive "e-bike chains". Apart from the fact these indeed come with many links, these chains seem to be overhyped.

So, replacing a chain for a MDM e-bike is easy but it requires selecting a proper new chain and having proper tools at hand.

 

[linklemming]

It is because the hub-drive motor acts on the rear wheel directly and independently of the rider's pedalling effort. To make it clear, fancy such kind of e-bike with a powerful motor and the throttle: The rider may stop pedalling completely and just apply the throttle: the bike is pushed by the motor. With the PAS system on a hub-drive, it is enough the cyclist is just pedalling because the very act of pedalling there is just another form of opening the throttle. (The cyclist can pedal lightly or strongly but it doesn't take any effect on the motor operation).

With the mid-drive motor e-bike, the amount of motor assistance depends directly on the rider's power input (which depends on how strongly pedals are pushed and how fast the cranks are spun by the rider = torque and cadence sensors are responsible for that). The combined rider's and motor's power is transmitted by the drive-train to the rear-wheel, and that combined torque is either multiplied by the drive-train for climbing or divided for fast riding.

These two systems are fundamentally different as to how the power is being distributed. Riding the hub-drive e-bike means "Oh, I'm always riding with the wind!" while riding the mid-motor one is like "Oh, I am a cycling superhero!" It is necessary to ride both types of e-bikes to really experience completely different feel of these two e-bike concepts.

To ride mid-drive motor e-bike slowly is easy: just downshift, pedal lightly and slowly. With hub-drive motor, riding slowly is impossible unless the rider throttles the motor back...

Are you aware that hub-drive motors CAN have torque sensors and can therefore add power based on human power inputs (force/cadence)?

I have two of such bikes (Juiced CCX and DIY GMAC build with torque sensor and CA3). I only ride bikes with torque sensors.

There are several others...although rare, they exist

 

[Stefan Mikes]

Are you aware that hub-drive motors CAN have torque sensors and can therefore add power based on human power inputs (force/cadence)?

Still, these motors do not work through the drivetrain.

 

[Johnny]

Still, these motors do not work through the drivetrain.

What do you mean ?

 

[Stefan Mikes]

Hub-drive motor acts only on the rear wheel. Mid-drive motor acts on the chainring, and as I wrote before, the drive-train multiplies or divides combined torque of the rider/motor from the chainring to the rear wheel. It gives completely different riding experience. Once, I made a small calculation and it turned out the Yamaha PW-X2 motor working over the 36/51 gearing produces 120 Nm at the rear wheel alone. Add to it the rider's own torque, also amplified.

P.S. That's why a hub-drive motor e-bike requires far more power for the same climbing capability than the mid-drive one. More powerful motor is heavier and requires far larger (heavier) battery for the same range. That's why all e-MTB from big name brands (that may actually be small companies) are mid-driven.

 

[Johnny]

Hub-drive motor acts only on the rear wheel. Mid-drive motor acts on the chainring, and as I wrote before, the drive-train multiplies or divides combined torque of the rider/motor from the chainring to the rear wheel. It gives completely different riding experience. Once, I made a small calculation and it turned out the Yamaha PW-X2 motor working over the 36/51 gearing produces 120 Nm at the rear wheel alone. Add to it the rider's own torque, also amplified.

P.S. That's why a hub-drive motor e-bike requires far more power for the same climbing capability than the mid-drive one. More powerful motor is heavier and requires far larger (heavier) battery for the same range. That's why all e-MTB from big name brands (that may actually be small companies) are mid-driven.

Stefan we all know why mid drives climb easier. I thought your comment was on torque sensing.

Also one should mention advantages of hubs too, at higher speed they are more efficient, easier to keep the speed, long lasting chains etc. Mtb is not the only type of bike around.

 

[Mike TowpathTraveler]

Perhaps because Mike's been waiting for eleven thousand miles to replace the chain?

Stefan: Obvious front chain ring wear aside, the issue of that and the chain all came to a head when I tried to climb what turned out to be a hill side too steep for the motor and my meager power could ascend to the top. So, about 3/4 of the way up, down I went.

And from that point onward, whenever I mounted the bike and started pedaling, putting pressure on the chain resulting in throwing it off the chain ring......so stretched the chain was.

I've no doubt had I not tried that hill side climb, I would have gotten another few thousand on the chain, even with that front ring looking like that. And I say that cause up to that hill climb, I had no drive train issues whatsoever.

I do question why manufacturers make a steel cassette and steel chain that mesh with a front chain ring made out of......aluminum.

 

[BobG]

My now obsolete BionX hub drive with torque sensor works seamlessly and silently. The torque sensor in the hub measures the tug on the chain and responds accordingly relative to the level of assist chosen. The stronger the tug the greater the assist. The bike will fly up hills up to 12% or so. Steeper than that, the speed diminishes and it won't be as strong as a mid drive but it will still greatly assist pedaling without over heating. It's nice to get some exercise!

I've retro-fitted my Bruce Gordon touring/gravel grinder keeping its original 3x9 gearing. With three extra batteries, one spare wheel/motor plus a spare console I hope to keep it running for years to come! The prospect of having to choose a future mid drive replacement with its "one size fits all" single chainring, huge cassette and wide Q cranks is daunting. Not interested in an upright fitness bike as so many ready made ebikes are.

 

[Sierratim]

I do question why manufacturers make a steel cassette and steel chain that mesh with a front chain ring made out of......aluminum.

I believe the smaller cogs on cassettes are steel to better withstand the drive torque on much fewer teeth vs the larger cogs and chain rings that are often aluminum to save weight. The smaller cogs are often made to be replaceable as they can still wear faster than the larger aluminum cogs, depending on your riding style.

 

[Johnny]

My now obsolete BionX hub drive with torque sensor works seamlessly and silently. The torque sensor in the hub measures the tug on the chain and responds accordingly relative to the level of assist chosen. The stronger the tug the greater the assist. The bike will fly up hills up to 12% or so. Steeper than that, the speed diminishes and it won't be as strong as a mid drive but it will still greatly assist pedaling without over heating. It's nice to get some exercise!

I've retro-fitted my Bruce Gordon touring/gravel grinder keeping its original 3x9 gearing. With three extra batteries, one spare wheel/motor plus a spare console I hope to keep it running for years to come! The prospect of having to choose a future mid drive replacement with its "one size fits all" single chainring, huge cassette and wide Q cranks is daunting. Not interested in an upright fitness bike as so many ready made ebikes are.

My experience is close. I love a quality direct drive hub with torque sensing, I love riding it and take it over any mid drive on pavement. Yet I think the best would be the two speed geared hubs that will handle both steep climbs and fast speeds. I don't know why no one is using them these days...

 

[Sierratim]

Stefan we all know why mid drives climb easier. I thought your comment was on torque sensing.

Also one should mention advantages of hubs too, at higher speed they are more efficient, easier to keep the speed, long lasting chains etc. Mtb is not the only type of bike around.

EDIT - I misinterpreted the Load Line on the Motor Simulator charts. My conclusions were based on this error and should not be used for anything except as lesson in reading more and 'talking' less.

I've taken my discussion down as it was base on incorrect interpretation.

 

[AHicks]

Sierratim, working from a practical perspective, something's broken.

When I ride my MAC12t powered bike (w/26x2.0 tires) at 15 mph (+/-) on a level pavement, it's usually pulling something in the area of 2-300w. The Ultra powered fattie, the same or maybe just a hair more. The wattage drawn by these motors is way less than what you are stating - assuming I'm following you correctly. If I run the charts for these motors, and use the BLACK (load) line, I get something MUCH closer to what my bikes are actually pulling. -Al

 

[B_Money_]

Unless you buy an expensive hub drive bike i doubt it will last long. I zip stoped making the hub drive for my 2014 izip e3 dash, so I put a rear hub bfang 500watt motor kit on from Amazon for 500$ and it just blew on my after only 800 miles in like 4 months or riding to work and friends house. My dash lasted Bout 3500miles then I stopped riding for 3 years went back to ride it after 3 years and the motor is shot. PROBLY BECAUSE I LEFT IT IN MY SHED IN NJ WHERE IT GETS REALLY HOT AND COLD OUT SIDE THROUGH THE MONTHS. Probably messed with the magnet glue.

Ps i think izip stopped making bikes with hub drive motor. Probably because inconsistencies based on where you live and store your bike. I lived in Florida for the 3500 miles I put on the bike, kept it in side when I wasn't at work.

I would go with a mid drive all day. But thats just me.