On Saturday, November 2, 2019 at 3:49:14 AM UTC, pH wrote:
On Tuesday, October 29, 2019 at 8:35:17 PM UTC-7, Andre Jute wrote:
On Tuesday, October 29, 2019 at 10:46:36 PM UTC, AMuzi wrote:

There just are fewer electric bicycles. So far...

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Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

I'm no longer so sure. I've of course heard all the talk of the coming e-bike revolution, but my own bike is now ten years old, and in that time I've seen precisely three e-bikes beside my own in a catchment are of 40-50,000 people. It is as well to describe them:

snip

Andre Jute
So how come I can't see the revolution I'm supposed to be leading?

Here in the Santa Cruz area I am seeing many more electric assist bikes.
I commuted to work for 15 years and saw virtually no electric bikes during the time...the occasional Currie-cycle.
I think what doomed those was the lead-acid technology. It would not take long for a non-battery savvy person to kill a lead acid battery.

The Li ion revolution seems to have saved the day.
So far I'm seeing bottom-bracket "pods" more than hub motors by about a 10:1 ratio.
I don't know the wattage of these things (I think that Bosch and Yamaha are the two main players...Muzi help me out here it there are popular others), but the 750 watt motor of your acquaintance/neighbor seems like it would be more than adequate, even for a Clydesdale as me.

Short answer: Lots around Santa Cruz so far. We'll see how they hold up over time.

pH

Mid motors just loom large in my mind because they're the only two I've seen on the road here, mine and the other guy's. But the electric bikes I know to be parked for good in garages are very likely all hub motors, because that's what was available back when there was a surge of interest. I too had a hub motor, as an experiment, before I installed the bottom bracket motor. I was not surprised when I burned out the hub motor in 3500 miles because I made up my mind before I installed it that a German-legal electric motor on a pedal bike is not a capital asset but an undersized consumable component with a definite if then unknown lifespan.

Scharfie's numbers are cockeyed, or else vendors saw him coming. (That wide swagger the techno-elite is unmistakable.) Bosch and perhaps others sell OEM motors with definitely legal power and crippled or low level software. It's what you get when you buy a top ride-away electric bike. In Germany you can buy an upmarket electric bike from Utopia and the other baukasten. The electric motor Utopia fits to their top, very stiff frames is very powerful for its rating, and probably long-lasting, but you pay for it and the thing is about twice as heavy as my installation on a Utopia Kranich. The software is crippled pedelec stuff, because all real Germans, and especially German cyclists and the manufacturers who cater to them, snap to attention when their lawmakers speak, and German lawmakers are responsible for a lot of the crap the rest of us cyclists have to put up with.

Smart people buy a good bike or frame, and electrify it themselves with a Bafang (also known as 8FUN, I swear I'm not making this up) BBS central motor and the very nice facia and software they supply with it, and the biggest battery they can afford. These Bafang motors run from 250W to 750W, but I don't see that any *cyclist* needs a bigger motor than 350W, because these Bafang motors are the natural successors to the BPM, also made by Bafang, which was for years the torquiest motor you could buy in any of its various size classes.

It's important to buy your motor from someone who will supply it including software untampered with. There are quite a few dealers who believe they are adjuncts to the police. They refuse to give you the thumb throttle supplied in the Bafang kit, they cripple software so that the top speed is 15mph, and, worse, so that you can't get at the nine performance settings built into the software, or the ability to have the motor give full torque regardless of pedal input. Compare the crippled software they think the law requires: When you get to a hill and your pedalling slows because of the incline, the power that the motor provides falls with your cadence. This is exactly arse about end; that is precisely when you need more power. I fitted the motor because my wife wanted to live up a hill that was too much for my heart, so if a dealer had done that to me I would have called on him to express my displeasure in person.

The other thing that is important if you do your own installation, is to buy the biggest battery you can afford. It doesn't matter that you don't need its nominal range. What matters is that the amount of oomph the motor delivers on a hill is directly related to instantaneously available current of the battery, and the bigger the battery is, the more current it has instantaneously available at any state of discharge. I call this the Coulomb rating of the battery. (The coulomb is the quantity of electricity transported in one second by a current of one ampere.) This is so important that Bafang on the fascia doesn't even give you idiot lights for the number of amp-hours left in the battery, but instead a graph that shows how much current you're drawing from the batter vs what is available: this graph doesn't move on the flat, regardless of what you demand from the battery, if it is big enough, of course, but near the top of a steep hill it starts falling fast; when it hits bottom, the motor dies (I think, I've never actually abused the battery that hard) even if the battery still shows fully charged on its own idiot light.

As I said, Scharfie's numbers are off. By about half. I fitted the Bafang centre motor, all the standard and best optional electronics, and the smallest dished chainring I could buy to preserve the Rohloff chainline, and a humongous best quality battery made with Samsung cells and EU approved control boards for charge and operation, and the cost was just over 800 euro, including carriage and all taxes, so around a thousand American dollars. I have no idea where Scharfie gets $1500 from, half more again than I spent; it must be featherbedding by his union chums.

One more thing: If you fit the smallest of the Bafang centre motors, and you aren't a kid but a responsible adult, you don't actually need a Rohloff gearbox. I had a Rohloff on the bike I wanted to convert already when I needed to electrify. NuVinci offers a very nice automatic CVT though the manual CVT is no hardship; either of those may do it if you remember to be smooth with the throttle.

Andre Jute
Hands-0n
Gotta sleep