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Re:First 100 miles on my E-Bike by username223 on Saturday December 30, 2017 @10:39AM (#16035664)
This. For the $1500 the author spent, he could have bought a decent bike instead of strapping a motor on a $200 piece of cast-iron junk.

Plus, a 1000-watt motor is ridiculous: that's the kind of power generated by a pro sprinter, and over twice what a pro climber generates on average. A 100-watt boost would be enough of an advantage to make most hills easy, and would probably weigh and cost far less.

Re:First 100 miles on my E-Bike by amiga-workbench on Saturday December 30, 2017 @11:31AM (#16035904)
I don't think you have tried out an eBike before, 1000W is just about enough to make most inclines easy. If I drop my BLDC controller down to 250W it makes things rather difficult. Remember you are carrying around the extra weight of a battery pack and motor.
Re:First 100 miles on my E-Bike by revelation on Saturday December 30, 2017 @11:45AM (#16035981)
Most humans can't sustain 250W on a simple ergometer for 20 minutes. At 1000W, you are a motorcycle, not a bike.

If that is what you want, fine, but then stick to roads, stay off bike paths.

Re:First 100 miles on my E-Bike by amiga-workbench on Saturday December 30, 2017 @12:11PM (#16036127)
Its a DC rear hub motor, I can throttle it fully up and still hold my bike in place. It accelerates poorly and has relatively little torque. I can get my bike up to the same speed manually with the benefit of the gearing all bikes have.

On even terrain I don't have any reason to be driving around at over 15mph (and I don't), but we do have morons who will, and that's why the law is so restrictive in the EU.

Re:First 100 miles on my E-Bike by weddpros on Saturday December 30, 2017 @12:32PM (#16036234)
Sure, morons always go by the law...

They don't bother with ebikes anyway, so they're reckless with a moped, which is way more dangerous.

The 250W limit in Europe is stupid (plus it shouldn't be a European law, it's not the correct scope).

Finally, you can be reckless with rollerblades or a bike, you don't need a motor. I guess it's more a problem of "250W is more than enough for people" just like 640kb was, for politicians.

Re:First 100 miles on my E-Bike by eesmith on Saturday December 30, 2017 @12:56PM (#16036360)
Lots of things have a boundary, even if the boundary is somewhat arbitrary. In most places there is a voting age, there is an age of consent, and there is a drinking age. These ages differ, because there is no clear-cut boundary.

Do you think there should be no power limit, or that it should be a different power limit?

I don't see why the regulations for electric bikes should be much different from gasoline bikes (aka, mopeds). If your e-bike is powerful enough, then it's comparable to a more powerful moped.

Do you think we prevent people from drive on the sidewalk because they will be reckless? I think the greater the momentum disparity, the more likely it is that an error, like loss of control, results in injury or death. This is a wider brush than "reckless".

Re:First 100 miles on my E-Bike by CydeWeys on Saturday December 30, 2017 @11:50AM (#16036012)
Are those two figures comparable though? Is an electric bicycle motor measured by its power draw or by its output? And either way, it's still not the same because at most that'd be measuring at the crank, whereas an ergometer measures at the pedal. So if I had to guess I'd say that a 1000W electric motor is roughly equivalent to, say, 500W output from a human on an ergometer (which of course is still way better than the average person can perform for any length of time).
Re:First 100 miles on my E-Bike by revelation on Saturday December 30, 2017 @12:22PM (#16036179)
It's hard to build an inefficient electric motor, and I'd think the headline figure is the motor power rating.

But even if we assume it's the power draw and the motor itself is terribly inefficient, we're still talking 80% efficiency? Chain drive is 95% efficient if badly maintained, but then the human power loses that, too, so we don't need to consider it. So we're still talking 800W, which is 3-4 times as much as needed to sustain 20 mph on flat ground, and utterly out of range of any human for any time period beyond a minute.

The power and speed limit of normal ebikes is a feature. It keeps us from making the same mistake we have with cars, which only ever got faster while driving discipline declined and were at any point beyond human ability anyway.

Re:First 100 miles on my E-Bike by Decade on Saturday December 30, 2017 @03:24PM (#16037321)
Correction: The headline figure is the motor’s maximum power rating. I tried an electric bike with a 350W hub motor, and on a moderate hill it did not have enough torque to move. Power = Work ÷ Time, Work = Force × Distance; 0 distance ⇒ 0 power.

I understand that mid-drive motors can deliver much more torque than hub motors. Maybe the OP is being realistic about what he needs in the Arizona hellscape where he lives.

Re:First 100 miles on my E-Bike by bjourne on Sunday December 31, 2017 @12:22AM (#16039477)
Perhaps if the rider is really heavy or untrained. :p I have a 500w motor and almost never have to use more than about 4/5 of the maximum throttle.
Re:First 100 miles on my E-Bike by amiga-workbench on Monday January 01, 2018 @08:33PM (#16049183)
A bit of both tbh, but that bike is getting me out 5 days a week and is helping a lot.
Re:First 100 miles on my E-Bike by dmurray on Saturday December 30, 2017 @11:21AM (#16035851)
100 watts would turn it back into a manual bike with some electrical assist. There's a place for that, but it's clear the author was looking for something more.
Re:First 100 miles on my E-Bike by mantas on Saturday December 30, 2017 @12:01PM (#16036079)
E-bikes are bicycles with electrical assist. Fully motorised bikes are mopeds or, well, motor bikes.
Re:First 100 miles on my E-Bike by dmurray on Saturday December 30, 2017 @12:20PM (#16036167)
Yeah, I'd count the author's bike as being pretty close to being a moped. Except that it might get regulated as an e-bike, and it is possible to use it as a normal heavy bicycle if he wants or if the motor fails.
Re:First 100 miles on my E-Bike by ebikelaw on Saturday December 30, 2017 @09:09PM (#16038946)
The law in many US states and most European countries views the machine in this article as a moped or motorcycle. It is throttle-operated, instead of being proportional to pedal torque, and it has no speed limiter. If it was limited to 20MPH, it could be a "class 2" or "type 2" e-bike in many jurisdictions. If it was pedal-operated and limited to 28 MPH, it could be a "class 3" e-bike. But as built, it's a moped. You need a license, registration, insurance, and a helmet to operate it.
Re:First 100 miles on my E-Bike by iamnothere on Saturday December 30, 2017 @09:33PM (#16039012)
Maybe the author lives in a state where this is fine? Not all places have the same laws.

The author made a cool thing and did everyone the service of documenting the process. Why is everyone so quick to crap on his project?

Re:First 100 miles on my E-Bike by Fricken on Saturday December 30, 2017 @01:21PM (#16036538)
If you can pedal it, it's a bicycle.
Re:First 100 miles on my E-Bike by CydeWeys on Saturday December 30, 2017 @02:27PM (#16036972)
I see a lot of deliverymen around here with beefy e-bikes who never pedal. The question of whether you can pedal seems academic if you never do. These e-bikes I'm talking about are functionally identical to electric mopeds (same power and speed capabilities); they just have pedals that go unused instead of a footrest.

The law recognizes this too, which is why e-bikes are primarily regulated by power output or top speed.

Re:First 100 miles on my E-Bike by dsego on Saturday December 30, 2017 @03:42PM (#16037464)
Moped = motor + pedal
Re:First 100 miles on my E-Bike by jordache on Saturday December 30, 2017 @10:47AM (#16035708)
> $200 piece of cast-iron junk.

He used an alu bike...

mechanical disc brakes worked for a decade before hydraulics.

Re:First 100 miles on my E-Bike by CydeWeys on Saturday December 30, 2017 @11:57AM (#16036056)
Mechanical disc brakes certainly do not work nearly as well as hydraulic disc brakes in high-power-output electric bike applications. What they "worked" on is manual bikes, but even for manual bikes, hydraulic brakes are superior; it's just that a manual bike isn't pushing the limitations of what mechanical brakes can do as often.
Re:First 100 miles on my E-Bike by jordache on Saturday December 30, 2017 @12:15PM (#16036143)
hydraulic mostly provides improved actuation via greater modulation resolution. Think about it - It's a hydraulic system vs mechanical. No cable stretch and no friction along brake housing. However greater modulation resolution is not a major benefit in the context of ebike. The bike is heavier so you just need sufficient braking power. A larger rotor radius would help more than going from mechanical to hydraulic.

hydraulic alone doesn't provide greater braking power vs cable pulled calipers.

Re:First 100 miles on my E-Bike by CydeWeys on Saturday December 30, 2017 @12:24PM (#16036194)
I get what you're saying, but in practice, cheap mechanical disc brakes also suffer from less braking force, whereas there aren't particularly cheap hydraulic disc brake systems, so all the hydraulic disc brakes do have better braking force in addition to greater modulation characteristics.

So to simplify the point I'm making, he needs better brakes.

Re:First 100 miles on my E-Bike by username223 on Saturday December 30, 2017 @11:03AM (#16035776)
> He used an alu bike...

My bad -- the name "IRON HORSE" threw me off. Still, the thing supposedly weighs 37.75 lbs., which is terrible for a bike. For $1500, he could get something with much better parts weighing 20-25 lbs.

Re:First 100 miles on my E-Bike by eesmith on Saturday December 30, 2017 @01:04PM (#16036421)
Ahem. Speaking with mock outrage, as someone who goes bike camping with front and back panniers and a tent, I'll point out that my bike is about 40 lbs, unloaded. Eg, https://www.koga.com/en/bikes/trekking/collection/worldtrave... . ;)

'Course, my average speed is about 8mph. I like to stop, look at things, and read the signs, and sometimes travel along hard-pack dirt roads.

Their e-trekking bike is about 54 lbs. I know what I'm going to get for myself when I get older.

Re:First 100 miles on my E-Bike by username223 on Saturday December 30, 2017 @01:16PM (#16036506)
That's some heavy hardware! A bike trailer is 3-4 lbs, and a 20-lb road bike is around $1500 new (far less used). You'll pay more in money or weight for a cross or mountain bike, but 40 lbs is still pretty painful.

EDIT: Pro deal is 50-60% of retail, so you can buy a used bike for about half of the sticker price.

Re:First 100 miles on my E-Bike by CydeWeys on Saturday December 30, 2017 @02:52PM (#16037110)
You may well pay more in aerodynamic penalty on the bike trailer than you would in extra weight on the bike itself, though. It merits calculation.

Also ... biking with a trailer just isn't fun. I'd much rather bike on a loaded-down heavy bike than on a lighter bike dragging a trailer behind it.

And there's the fact that I'm sure you must be underestimating something, because a bike trailer has additional weight from its frame, wheel, and tire to add on that a fully-loaded bike does not. I don't see how it's possible that, for equal carrying capacity, adding a trailer could somehow reduce total mass.

Re:First 100 miles on my E-Bike by eesmith on Sunday December 31, 2017 @07:09AM (#16040293)
I don't bike particularly fast, so I'll bring up other factors.

The wheels of the bike trailer add additional rolling resistance, and more I think than putting the same weight on two wheels. That is, the trailer wheels are smaller, which means there's more force against the direction of travel.

Most bike trailers have two wheels side-by-side. If you are biking down a dirt road, then odds are there are packed ruts side-by-side, with a grassy strip in the middle. With a 2-wheel bike, it's easy to go along one of the ruts. With side-by-side wheels it's more likely that one of the wheels will be in the grass.

(My spouse uses a trike, and has this problem.)

I think username223 doesn't understand where the weight comes in, and is estimating what the weight "should" be based on a road bike + trailer combo.

A bike like mine, for bike camping, is heavier than a road bike. I also use it for dirt roads, so it needs to handle more shocks and vibration. The racks and fenders, and of course the gear, adds more weight. There are also not one but two kickstands on mine - the one on the front tire is needed if I'm carrying front panniers, because otherwise the wheel may twist and the weight pulls it down.

This then calls for a stronger frame, which adds even more weight.

https://en.wikipedia.org/wiki/Touring_bicycle gives more on the topic.

Re:First 100 miles on my E-Bike by CydeWeys on Saturday December 30, 2017 @02:31PM (#16036997)
Can I just say, it seems weird to me that that bike doesn't have disc brakes given its intended uses for bike camping? How does it handle long descents and/or rain? The serious bike camping bikes that I've seen have both disc brakes and caliper brakes, for redundancy and ability to handle long declines under heavy load that might burn out just a single set of calipers.
Re:First 100 miles on my E-Bike by eesmith on Sunday December 31, 2017 @05:34AM (#16040079)
That Koga-Miyata is a "serious bike camping bike", so I don't know what to say.

I haven't found it to be a problem. Mind you, I go slow, even downhill. I don't usually like biking faster than I can run.

Re:First 100 miles on my E-Bike by jordache on Saturday December 30, 2017 @11:27AM (#16035890)
In an e-bike assisted context, the extra 10-15 lb, most of which is non-rotational weight is negligible.

A 20-25 lb steel bike with sufficient robustness does not really exist for $1500. Something like a surly ogre is about 30lbs. To shave off that extra 5-10 lbs you're looking at some very performance oriented parts and/or construction with extremely elevated prices.

Re:First 100 miles on my E-Bike by kevin_thibedeau on Saturday December 30, 2017 @01:03PM (#16036412)
It wasn't that hard to find 20 pound aluminum road bikes before CF took over.
Re:First 100 miles on my E-Bike by jordache on Saturday December 30, 2017 @02:08PM (#16036829)
uhhh you don't want to electrify a 20lbs alum road bike.

when electrifying you value robustness over light weight. The energy from the motor more than makes up for the few extra lbs it has to haul.

Re:First 100 miles on my E-Bike by CydeWeys on Saturday December 30, 2017 @02:37PM (#16037031)
Yeah, some people don't realize that what you want to electrify is more akin to a hardtail mountain bike. You want big sturdy tires that can handle hitting an imperfection in the road at high speed, and front suspension helps for the same reason. Bigger tires allow for better braking, too.

Riding an electrified road bike at 30 mph all the time sounds terrifying and potentially dangerous.