[throwaway76543]

25kph is a meandering speed for an adult on a road bike. 30kph is quite common and 35kph isn't unusual. I regularly ride paved commuter trails with bikes doing all of those speeds and it really isn't a problem.

The idea that a 10kph speed differential between vehicles is a problem doesn't make any sense considering you have a 25kph speed differential with stationary objects on your commute. Or 50kph if you consider two 25kph bikers passing each other.

It's really a non issue. 25kph is an unreasonably slow limit. The energy levels involved in a bike crash simply don't compare to the potential for damage in a car crash, in part due to the lack of mass.

[blattimwind]

> It's really a non issue. 25kph is an unreasonably slow limit. The energy levels involved in a bike crash simply don't compare to the potential for damage in a car crash, in part due to the lack of mass.

If I crash my car at 50 km/h collision speed chances are quite good that I'll be sleeping in my own bed that day.

If I crash my bike at 50 km/h collision speed, I'm lucky if I survive.

Energy levels are irrelevant. When I'm riding a bike, my body is the crumple zone.

[throwaway76543]

We're talking about two vehicles colliding with each other. The mass of the vehicle is absolutely relevant.

Crashing a bike at 30mph/50kph is not as dangerous as you suggest, you can find plenty of higher speed bike crashes on youtube with no fatalities. Road rash and broken bones are the most likely outcome. I've crashed at this speed and I walked away with road rash only.

There is an enormous difference between a bike crash which results in sliding along the pavement and a car crash.

[davidgould]

I'm not persuaded that finding "plenty of higher speed bike crashes on youtube with no fatalities" equates to "safe".

[throwaway76543]

If your opinion isn't informed by data then what value could it possibly have?

[gnulinux]

Your argument doesn't make sense to me. When do two bikes pass each other? That literally never happened to me, if it did I would yell the other biker saying they're going the wrong direction. When are there stationary objects on the bike lane? When a car is stopping, and that annoys the hell outta me and by no means ok or the norm. If there is a >10kph differential between me and a bike I immediately try to let them pass me. Why are they going so fast, threatening all bikers' lives?

> It's really a nonissue

Well, it may be for you. I've been biking for 15 years and it really is an issue for me. I don't want pedestrians, cars or fast objects on bike lane. If there are a lot of bikes on the bike lane and convoy goes at 30 kph that's perfectly fine, I go 30 too. But if people go 25 and some asshole is trying to go at 35, then we have a problem.

[clarry]

> Well, it may be for you. I've been biking for 15 years and it really is an issue for me. I don't want pedestrians, cars or fast objects on bike lane. If there are a lot of bikes on the bike lane and convoy goes at 30 kph that's perfectly fine, I go 30 too. But if people go 25 and some asshole is trying to go at 35, then we have a problem.

Speed differentials like that are the norm where I bike. Bikes mainly share a section of the road with pedestrians. So you get people standing around, going 0kph; you have people walking 5kph; people jogging 10kph; kids, the elderly, and people loaded with groceries biking 15kph; normal cyclists who aren't in a hurry doing 20-25kph; fit cyclists and people in a hurry up to 35-40kph. I don't think anyone's got a problem with it really. We kinda know how to share the road, even with people going different speeds.

Drivers, mainly, are afraid of fast cyclists jumping red lights.

I, as a cyclist, am more concerned about dogs, but that phenomenon hasn't bothered me much in the recent years. I once got bitten by a dog that gets excited by cyclists..

[r00fus]

Seriously people doing 40kph in a city street? The average for a Tour de France pack was somewhere between 26-29mph ~= 41-47kph. That's assuming no stop signs , obstacles and plenty of the pack grabbing a wheel.

I think you're over-estimating average possible speed on a city route.

[1] http://slocyclist.com/whats-the-average-speed-of-tour-de-fra...

[clarry]

The speeds I listed were not averages, but instantaneous; the purpose were to outline the speed difference between different moving things that share the path.

Yes, more or less any grownup in fair shape can pedal 40 kph on a flat, as long as they don't run out of gears. Maintaining over 40 kph average (which means going much faster at times) for the duration of a long race is a completely different thing.

And yes, some people actually like to sprint like hell for fun. Sometimes I do too.

Think about it for a moment. Club cyclists often aim to average around 27 kph for something like a 80 kilometer trip. Hitting 40 on a nice flat or downhill section on your commute of 3 km is nothing.

[r00fus]

I think we'll have to disagree about what the 25kph limit means. It allows untrained, unprepared, possibly drunk folks to man a vehicle which does all the work for them at that speed.

You prefer freedom for the avid electric cyclist, I want safety for pedestrians and slower cyclists.

[clarry]

Why are cycles held to a higher standard than cars in that regard? People drive without licenses, and they DUI, and they drive without appropriate training, and they text and drive, and they kill people. We still don't limit the whole class of vehicles to a maximum speed that won't kill.

This whole thing is so backwards. These limitations just reward people who take the big metal box, and punish those who would prefer a combination of muscle power and some electric aid.

Also, I think you're seriously overestimating the amount of danger 250W can do. I still hold that it's very unlikely for a drunk cyclist to do any significant damage to anyone except themselves with that much power, speed limits or not.

Aren't you focusing the potential negatives a little too much here? Allow a few bad apples to ruin the whole thing? If cars were invented today, you wouldn't let them on the road.

Vehicular traffic is all about taking a controlled risk for convenience. I think we could take the risk of removing the speed cap on low power bicycle motors and we wouldn't see a massive surge in pedestrian/cyclist injuries or deaths or accidents in general. Even in the hands of a drunk idiot, the bike is still far less dangerous than a car, and easier to evade should it come to that.

[boomlinde]

My daily commute (when I rode a bike) was much shorter than a Tour de France stage. You have to consider that that's the average over more than 20 consecutive day-long legs.

I think you are underestimating the difference between maintaining an average speed during a whole day and maintaining that same speed for 20 minutes.

[throwaway76543]

Are you thinking only of riding on roads? I often ride on paved bike trails. They're usually maybe two meters wide with mixed pedestrian and bike traffic.

Even in a bike lane you're still passing stationary objects. You asked "when would there be any" and then immediately gave one of the most common examples. An even more commmon example, of course, is the ground you're riding over. You have a 25kph speed differential to the earth.

There is no serious threat to your life from a bike going 35kph. I've crashed at that speed or faster numerous times on downhill courses. No need to be so melodramatic.

[davrosthedalek]

No, you haven't. You maybe have fallen at 35 kph. That's different. If a car hits you standing still at 35 kph, that's about the same energy as you crashing into a wall riding a bike at 35. I would not recommend it.

[throwaway76543]

I think you might be confused. We are talking about the danger involved with two bikes going the same direction with a 10kph speed differential (25kph / 35kph). When crashes like this happen, people fall off their bikes.

I mentioned that I have fallen off at this speed with relatively minor injury. People generally do not die from falling off a bike at 35kph.

Nowhere did I say anything about being hit by a car at 35kph not being dangerous. No one is saying that.

[davrosthedalek]

Actually, I think you are confused. You spoke about passing stationary objects, and you wrote you crashed at 35. I wrote that you didn't, you fell down with 35 (which you seem to concede). If you would have crashed with 35, in something hard, parked car, tree, wall of a house, or another stationary object, it's as bad as if a car hits you with 35, which indeed is very dangerous. (It's actually slightly worse, because a) the car is designed to minimize damage, and the wall is not, and b) a house is often heavier than a car, car and house building practices in the US non-withstanding)

[throwaway76543]

I spoke of the ground being a stationary object (the most common one anyone will encounter, as I put it). I did in fact fall onto the ground.

Crashing into stationary objects is indeed a much greater danger than a fellow cyclist riding with a 10kph speed differential. That was my point, which you are now re-stating.

Hope that clears up any confusion!

[boomlinde]

> Your argument doesn't make sense to me. When do two bikes pass each other? That literally never happened to me, if it did I would yell the other biker saying they're going the wrong direction.

On a bike path?

> When are there stationary objects on the bike lane? When a car is stopping, and that annoys the hell outta me and by no means ok or the norm.

(Practically) at pedestrian crossings too, but I assume that GP is referring to objects along bike paths/lanes like trees, sign posts etc.

> If there are a lot of bikes on the bike lane and convoy goes at 30 kph that's perfectly fine, I go 30 too. But if people go 25 and some asshole is trying to go at 35, then we have a problem.

What if there's that one guy going at 15 km/h when everyone else is at 25 km/h? This also assumes that there is a convoy to speak of. I'd regularly ride mostly alone, only occasionally passing other people.

So to summarize, the argument probably doesn't make sense to you due to differences in culture, city planning population density... You name it.

In a dense city with a lot of bicycle riders I personally think that a 25 km/h limit is reasonable, but on a rural bike path without crossings or stops I'll easily exceed that comfortably and safely.