e-Bikes – Let’s talk

[creadinger]

@lordofthemark 164034 wrote:

…MVT from 4MRT to the 14th street bridge (which as it happens, is a place where ebikes are currently banned, and which I consider problematic for fast riding in general.

Wait, wait, wait…. ebikes are banned on the MVT? Then how come I periodically get passed by a dude on an ebike on that stretch?

To be fair, compared to some prior experience, he passes pretty responsibly and is lit up like a Christmas tree as well.

[cvcalhoun]

@dbb 164108 wrote:

Everybody should be aware that we need to say what needs to be said regarding e-bikes by 5 Nov 2017 (shift off daylight savings time), at which time we will shift to the regularly scheduled debate about bike lights on the trails that are too bright/annoyingly flashy/poorly aimed/not used.

Thank you.

What, I’m not allowed to complain about bike lights on the trails that are too bright/annoyingly flashy/poorly aimed/not used now? How am I supposed to keep these things straight? I know, let’s have an argument about which dates are appropriate for which arguments.

[Judd]

@cvcalhoun 164172 wrote:

What, I’m not allowed to complain about bike lights on the trails that are too bright/annoyingly flashy/poorly aimed/not used now? How am I supposed to keep these things straight? I know, let’s have an argument about which dates are appropriate for which arguments.

Given your work schedule, you get permission to complain about bike lights year round and that the metro doesn’t run late enough.

[dhs1963]

I think every can agree that I am good with my e-bike.

I can not ride the hills anymore. I am 53, have 4 cardiac stents, and am a cancer survivor. I stopped exercising during the cancer struggles about 5 years ago because of general exhaustion. Because of my cardiac issues, I can not let my pulse get over 120. I bought the e-bike so that I could get some exercise and so I can ride with my teenage daughter. Also, on occasion, commute to work (too hot in the summer though).

When I am with my daughter, I am going her speed, which is between 12 and 16 mph. When I am alone, I am going an appropriate speed. If I am the only bike on the trail (say at 6 AM on a Tuesday morning), I might average 20-22 on the flats. If it is crowded, I will only pass when it is safe. One advantage of the e-bike is I am not as invested in my momentum.

I am usually tired when I get back from a ride, which varies from 6 to 20 miles, so I know I am getting exercise.

My bike is a Trek XM 700. It is a speed pedalec, with top assist speed of 28 mph. It will go faster, but I am doing all the work above 28. My bike does not have a throttle; instead, sensors measure the torque applied to the crank and assist based on that; when riding, it feels like a bike.

[Judd]

@dhs1963 164242 wrote:

My bike is a Trek XM 700. It is a speed pedalec, with top assist speed of 28 mph. It will go faster, but I am doing all the work above 28. My bike does not have a throttle; instead, sensors measure the torque applied to the crank and assist based on that; when riding, it feels like a bike.

This is interesting. So when pedaling it feels like a normal bike? Can you turn the pedal assist on and off?

[Dewey]

WABA’s Greg Billing, Montgomery County’s Casey Anderson and ebike opponent Paul Basken are on today’s Kojo Nnamdi show talking about ebikes on DC area trails.

[Judd]

I’m going to call in and just start reading this thread bulldozer style.

[Crickey7]

It’s never the wrong time to argue about fenders.

[dhs1963]

@Judd 164249 wrote:

This is interesting. So when pedaling it feels like a normal bike? Can you turn the pedal assist on and off?

Yes. It has five levels: Turbo, Sport, Touring, Eco and off.

On flat:

Turbo feels like riding down hill (3% grade)
Sport is more like a 2% grade,
touring is like a nice tail wind
Eco makes it feel like a regular bike (no extra weight)

Off is hard because of the extra weight.

Trek makes a good product.

And it has fenders.

[SolarBikeCar]

One point rarely discussed is the stopping distance. E-bikes are heavier but generally have front and rear disk brakes. On the downhill they go about the same speed as a traditional commuter bike. In a panic stop I would expect disk brakes to greatly outperform a single coaster brake or a pair of v-brakes. Should we ban bikes without disk brakes on trails because riders can go faster than 30 downhill but can’t stop adequately? Ebikes are used to improve uphill speed where stopping quickly isn’t hard even without disk brakes.

[DismalScientist]

@dhs1963 164280 wrote:

And it has fenders.

Well then it should be banned based on the pansy-assed nature of the purchaser.

[Sunyata]

@SolarBikeCar 164286 wrote:

One point rarely discussed is the stopping distance. E-bikes are heavier but generally have front and rear disk brakes. On the downhill they go about the same speed as a traditional commuter bike. In a panic stop I would expect disk brakes to greatly outperform a single coaster brake or a pair of v-brakes. Should we ban bikes without disk brakes on trails because riders can go faster than 30 downhill but can’t stop adequately? Ebikes are used to improve uphill speed where stopping quickly isn’t hard even without disk brakes.

I really should not feed the troll… But SCIENCE.

You do realize that most traditional commuter bikes range between 20 and 30 pounds, correct? And most e-assist bikes are going to weigh at LEAST double the lower range of a non-e-assist bike. Obviously, it is going to be harder to stop a heavier object when it is in motion (did you not learn this in your elementary school science classes?). Therefore, your argument is moot. The stopping distance of a 20 pound bike with sub-par mechanical rim brakes is still probably going to be shorter than the stopping distance of a 50 pound e-assist bike with 160mm hydraulic disc brakes (assuming the load is the same). (Now I kind of want to do an experiment, but none of my bikes have rim brakes.)

This is why larger, heavier vehicles have bigger and stronger brakes than smaller, lighter vehicles.

[hozn]

Science is not SolarBikeCar’s strong suit, despite being a self-proclaimed “engineer” – I guess IT doesn’t require grade-school physics

Or, apparently, experience with bicycle braking systems. The main argument for disc brakes is not stopping distance, but consistent power in wet conditions and better modulation. Pro rim-brake arguments (why?!) often miss this point and start by asserting that even crappy brakes on a bicycle are usually capable of/sufficient for breaking wheel traction. I used to love that feature on my coaster-brake BMX … Sure, disc brakes stop harder with less muscle input, but I’d be surprised to learn that in any sort of typical brake-hard emergency stopping situation disc brakes made for shorter stopping distances. Maybe vs rim brakes (not coaster) in the wet … Someone could do a study … (ugh, science again!).

(I do think that disc brakes give more control, but I think most people — certainly myself included — are not going to be feathering brakes in an emergency stopping situation.)

[huskerdont]

@hozn 164291 wrote:

Or, apparently, experience with bicycle braking systems. The main argument for disc brakes is not stopping distance, but consistent power in wet conditions and better modulation. Pro rim-brake arguments (why?!) often miss this point and start by asserting that even crappy brakes on a bicycle are usually capable of/sufficient for breaking wheel traction. I used to love that feature on my coaster-brake BMX … Sure, disc brakes stop harder with less muscle input, but I’d be surprised to learn that in any sort of typical brake-hard emergency stopping situation disc brakes made for shorter stopping distances. Maybe vs rim brakes (not coaster) in the wet … Someone could do a study … (ugh, science again!).

It’s not completely scientific despite it calling itself science, but GCN did a comparison. It’s a fun and useful comparison, despite the fact that they haven’t controlled for any variables etc.

https://www.youtube.com/watch?v=t0hKMgUEku4

Oops, this is the better video for stopping distance.

https://www.youtube.com/watch?v=uHFSSXOSnxs

[gibby]

@SolarBikeCar 164286 wrote:

Ebikes are used to improve uphill speed where stopping quickly isn’t hard even without disk brakes.

Based on e-bikers I’ve seen on the MVT and in DC, they are also used to pass people on a flat, crowded trail doing 20+ mph plus, and also to dangerously cut off cyclists starting up from a red light.

[Author]

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