I don’t know about you, but I pretty regularly have my chain derail on my bike (at least a few times per season). Then I end up with grease on my fingers as I fix it which can be a big inconvenience.

Do you regularly run out of power on your chain powered bike though? I get the feeling this system requires a battery (it even mentions battery in the article), and most of the actual power comes from that. The question is, will the generator make enough power to get you moving if the battery is totally flat? I kinda feel like no, you'd have to sit there and pedal it just to charge it up, and then it would move you a few feet. Or you're going to be pedaling really fast, and moving nowhere.

They claim to be 5% less efficient than a chain. So with a dead battery, you'd be limited to a speed of 95% of what you could do on a normal bicycle. That's if you're already moving. If you were at a dead stop I imagine you'd need to pedal a few strokes to get enough charge to get enough torque to overcome the stiction.

Where do they claim that efficiency? I'm pretty skeptical... Chain+Derailleurs can be 98% efficient IIRC

Electric motors/generators are in the same range. Also I doubt they need to target the best possible chain bikes in order to be a viable solution.

Since it has a battery and the battery is (most likely) chargeable, a little loss of efficiency is inconsequential. On the other hand, having an actual physical chain on an electric bike seems indeed unnecessary - at least for less sporty applications, where things like "feel" or precise power delivery are not important. The end result will be a simpler, more reliable bike. Not to mention better looking.

I googled Schaeffer Free Drive efficiency.

A Tesla motor is 98.5% efficient, so a generator and motor combo being 93% efficient does not sound like a stretch.

You need to get your derailleurs adjusted. I bike almost every day and it never happens to me, even when I do inadvisable hard shifts.

Been there. If you're riding a 1x drivetrain, a narrow-wide chainring will greatly reduce chain drops. A conventional chainring is designed for the chain to be thrown off easily, and the front derailer keeps it there. On a 1x system, the ring can be designed differently.

Hey thanks for this. I realized one of my bikes has been built wrong since I got it 15 years ago due to this comment.

Not really a normal thing;tTake your bicycle to a bicycle shop for diagnosis and repair. It make take a follow-up visit. Sometimes issues around dropping chains can be a bit complex to diagnose.

It only happens once a season or less for me and is almost always due to adjustment problems. And 90% of the time I can get it back on without touching the chain by using the front or rear derailleur.

If you're riding a single speed bike and the chain regularly derails, then that definitely sounds like a chain tension or alignment problem.

If your chain isn't too badly fallen off, you can usually just shift in the opposite direction of where it fell off and the derailleur will usually get the chain back on without having to get your fingers greasy.

Be careful when you do this so as to not apply too much power when you're trying to do this. If you're in a really high gear and it happens, you can get off, hold your rear tire off the ground and turn the pedals. Works 90% of the time unless you got your rear chain jammed between the cassette and the spoke.

Edit: You can very often see this if you watch professional bike racing. When the mechanics change a rear tire it will almost always knock the chain off of the front chainring. They'll just shift into the proper direct (low if it's off the high side and high if it's off the low side) and then spin the cranks and the chain will come back on.

I've gone entire seasons of hard mountain biking and touring without having my chain come off. I think your bike might need an adjustment or maybe you have a worn chainring.

1. Check your limit screws. Park Tool has nice Youtube videos for adjusting these.

2. If it's the rear derailleur, it may be bent (especially if your limit screws from step 1 are maxed out). You need a derailleur alignment gauge (or just take it to a shop) to verify.

If it bothers you that much the solution is a belt drive, which is still more efficient than a generator.

Wait until your chain gets ransomware

It's really catastrophic when the drive chain's watchdog timer has to reset it because some function went awry.

Not a normal thing. My chain never goes out. Only on janky beater bikes it did. To the bike shop you go.

Tuck a pair of nitrile gloves under the saddle or into your toolkit. No greasy fingers.

Have you seen a high-end bike? The gears have batteries, electric motors, microcontrollers, and sensors. You'll also find wireless power meters, GPS, and even radar sensors for traffic on a contemporary bike.

You get the idea. At the leading edge, bicycles are already extremely complicated. If we're comparing this idea to a bicycle from 2002, it's complicated. But I'm not sure that it's that complicated compared to the kind of bike you'd find in the roof rack of an Audi S4 Wagon :-)

I've seen them, even rode some bikes with electric shifters, but still don't want the complexity. One of my bikes is over 20 years old with the same Ultegra shifters, I haven't done any maintenance other than lubing once a season and they still work fine. I'd be surprised if the battery on electric shifters lasts that long.

You're describing a high-end e-bike, which is basically an e-motorcycle with less regulation.

A high-end regular-bike has electronic shifting and a power meter and that's about it. And you're talking many thousands of dollars worth of road bike. It's like seeing a Ferrari or a Lambo rolling down city streets. They exist but they're rare.

Yes, but we're discussing technology that will also be rare. It's not like these chainless electric drive systems will appear on big-box sporting goods store bicycles, so why compare it to a mass-market affordable bike's technology?

I think it's reasonable to compare a leading edge technology to a leading-edge existing product. Otherwise, it's like it's 2007 and we're complaining that this newfangled iPhone thngie can run out of battery in a day, while my POTS telephone works even in a blackout.

Yes, true, but apples, oranges.

Not necessarily. Shimano Di2 electronic shifting was introduced all the way back in 2001 and has been among the standards for high-end road bikes for many years now. It has all of those components. The electric motor doesn't have to drive the wheel.

One comparison is to e-bikes.

Which often have most of that and a chain too.

But also, e-bikes can let you ditch gears, which add complication.

But I think the main selling point is that you can seperate the sitting/cycling position from the driven wheel in interesting ways.

The selling point might be to finally have an "automatic" bike. Standard derailleurs are basically like having a stick shift on a car. The rider has to be trained on how to use them and they will make errors like leaving the gear setting too high when going on an uphill and then being unable to downshift because they aren't turning the pedals fast enough due to the high gear ratio.

This is literally just get on and start pedaling and the bike figures out the rest. It even makes e-bike controls super easy, since you can just set a speed and start pedaling and it will supply just enough juice to make up the difference.

The obvious downside is that it's going to be less efficient than a chain drive, because nothing beats a chain drive. But if you basically get the benefits of an e-bike for free then the efficiency loss isn't a big deal for the rider.

There's at least one existing hub drive ebike that uses this model.

It has a single gear, you can spin the pedals backwards to engage full regen, but the secret is that its usually doing a little regen which it stores and uses to help on hills and when accelerating from a standstill.

I am surprised automatic shifting technology doesn't exist. Wireless electronic shifters are readily available now, in addition to power meters. We have devices to shift and devices to tell us when to shift. All that is needed is to marry the two together.

It does exist, in the form of a CVT and controller invented by a company called NuVinci. I built a cruiser bike with the manual CVT version years ago. It worked but the hub was very heavy. If you were stopped in high gear and you pushed down on the pedal really hard to start going it would occasionally slip. Once you got going it was pleasant to use but don't expect to win any races.

They must not have sold very many of them because Fallbrook-NuVinci went into chapeter 11 and enviolo bought the tech.

https://enviolo.com/products/

The Vanmoof bikes have automatic shifters. I don’t like them because they are unpredictable, and you feel the difference. It’s jarring. The Cowboy is single speed, which works pretty well because of the motor. That’s my preferred configuration. But at high speeds it does feel like I’m at a spinning class, and it sounds like this system could fix that.

Lets be real, the selling point of this nonsense is that you can ride your electric motorcycle on a bike path and pretend it is a bike because it has pedals.

Personally, I don't get the hate over people using e-bikes on bike trails. While I am still fully pedal powered I have no problem with other people using e-bikes. Especially if the alternative is for that person to drive somewhere in a car.

Maybe in other areas people are doing 60kph on bike trails or something, but that's not what I see around me. They seem to top out around 20kph or so, which makes them basically just bikes as far as traffic flow is concerned. Sure they will zoom past you on the uphills, but who cares? It's not hurting me or anybody else.

There are lots of overpowered e-bikes with chain + gears, where the power going through the pedals is maybe 5 % of total power, and the rest is electric. This doesn't change or bring anything new to the table.

Far more complicated that a traditional bike. But compared to e-bikes, this avoids a lot of the complex mechanical bits.

I've had this system in mind for years, I think for cargo bikes with long chains, this will be a clear winner.

Bike drivetrains can require a fair amount of maintenance. Also a normal chain derailler system requires at least four sprockets, two in the derailler, one in the wheel, and one in the bottom bracket. Anything less is likely to be less reliable.

You can expect to change the chain every 5000km. In theory a fully electric drivetrain could last forever.

All I do is lube mine and its been a gem for years now. People preach that there is this whole maintenance regimen and you have to be this hobbiest watchmaker to deal with bike gear ratios and such and such, yet most bikes just sit in the garage with the lube that came on them from the factory and work fine. Go to a college and see all the 50 year old 10 speeds lined up in the racks. If you have a 50 year old piece of hardware in such high use that doesn't seem like its this unreliable untrusty system to me, quite the opposite. Especially compared to like anything else in transportation, like a car that might incur thousands in repairs over its life. How many 50 year old cars are parked at the college? How many cars are even over 25? Even a skateboard is less reliable; take a skateboard out in the rain and the bearings are fouled and the deck may even warp. You can even get bike tires that make flat tires practically obsolete short of hammering in a nail because they use kevlar like a bulletproof vest. Literally bulletproof tech.

Your phone is way more complicated than your bike and the hardware probably fails less often.

I've had my bike 10 years. How can the hardware fail on a bike? Throwing it off a cliff? Meanwhile, the laundry list of hardware issues I could list on my phone probably affects every component in the stack over my decade of owning various smartphones. Each dying due to some faulty hardware issue, such as the radio giving out and dropping calls or the jacks getting loose or various other issues.

My phone doesn't sit out in the sun/rain/snow at a bike rack and doesn't have any substantial moving parts.

I think I didn't articulate my point well. It's that complexity isn't a 1 to 1 mapping to reliability. There is plenty of complex equipment that fits your criteria. My pool pump is full of electronics, has moving parts, sits in inclement weather, and lasts for years. There is equipment that can sit near the combustion chamber of a rocket experiencing extreme g forces, pressure, and heat and survive. It can be engineered.

Phones tend to get pretty nice treatment compared to bikes. Bikes are constantly stepped on and rubbed against pavement.

Because if something goes wrong with your phone you probably won't be able to fix it. Compared to a bike where most anything can be repaired.

It's a single unit, you just replace it, like you would a broken gear. You can't fix a broken gear unless you weld it.

Idk, if you tried to use your phone as a bike I bet it would fail pretty quickly.

I don't get your argument. What I'm saying is that complexity isn't necessarily directly correlated to reliability.

Sure, but a hammer is both simpler and much more reliable than a phone. My point is that it is meaningless to compare items with completely different functions (I would say apples and oranges, but it is more like apples and rocks).