[lloeki]

> Biking at 45-48 MPH is rare, dangerous, and free of tripping hazards which I think are a much larger concern

Two decades ago I was doing downhill MTB. On a road section it was quite frequent for me to reach those speeds†; and that's with a MTB (tuned to that end), friends†† with road bikes reached these speeds with ease, some of them regularly hit 80-90kph on specific sections.

One of the wide hairpin turns happened to be littered with gravel, and as I was banking for the turn the bike wheels started zipping off laterally as it the ground was ice, propelling both of us sideways at full speed towards the downward outer bank.

Luckily a) I had slowed down to approach the turn so I was going more like 45-50kph and b) the bike had much less ground grip than my body so it flied away while body-ground friction (painfully) slowed me down to a stop before I hit any tree or rock down the bank. Sheer luck had it that I walked away from the event with only a few bruises and a lot of scratches (one of my elbows still bears burn scars)

† Top recorded speed ever was 74 kph, at which point gear ratio was such that `cat pedalling > /dev/null`

†† c.a 1995-1999 they biked regularly with the then young Julien Absalon (I only biked with him once): https://en.wikipedia.org/wiki/Julien_Absalon.

[Retric]

‘On specific sections’ doesn’t mean people are spending a lot of time doing something. If you’re going downhill at 45+ MPH you quickly run out of hill.

I doubt the total time by any bike rider over 45 MPH was 0.1% of the total time people ride bikes.

[LargoLasskhyfv]

I do that on flat grounds with a roadbike, and can hold that for about 5 minutes, then falling back to about 60 to 65 kph, which I can hold for an hour, after which I usually am where I wanted to be. Rarely doing longer rides anymore. Usually at sea level.

That thing where you are 'running out of hill fast' I'm doing comfortably with 80 to 85 kph, and sometimes when in a 'real crazy' mood, and weather is allowing it (strong gusty winds, and possibility of black ice NOT good) with 90 to 95 kph. Though I'm really having to pedal like mad then, like in 1st gear, even faster.

Usually anywhere between 2000 to 4300m above sea level.

Got myself 2 really nice roadbikes recently, after having ridden an antique citybike with only 3 gears for almost 2 decades now.

It's like I'm young again! Unbelievable! :-)

[Retric]

> Can hold that for about 5 minutes, then falling back to about 60 to 65 kph.

If you’re suggesting doing 60 to 65 kph for an hour on a normal road bike after 5 minutes of 75 kph, I simply don’t believe you.

The world record 1 hour time on ultra flat indoor terrain set in 2014 was 51.852 km (32.219 mi). It’s climbed since then but your suggestion of ~63 kph for a full hour on a roadbike comes off as silly unless your using serious electric assistance.

[LargoLasskhyfv]

I believe that you don't believe me, because that's what I always got. Except when on rare ocasssions ppl followed me with a car or motorbike. OR I pushed them to ride like they couldn't believe when they rode with me, which was also rare.

Can't do anything about it. Shrug. :-)

[LargoLasskhyfv]

A long time ago, 1989 or 1990 I went with 65kph into a larger roundabout at around 4 AM, with only one car in it, a Citroën 2CV. As usual, the thing was SLOW. I thought I'd could overtake it left, while staying behind it, but not much. What I didn't think of was the possibility that it would brake right there and then to exit into a small private driveway directly adjacent to the roundabout, instead of the regular exits.

So I touched the thick rubber lip of its back bumper at its far right side, almost the corner with my front wheel, while already being banked right by about 30 to 45 degrees (because turning right in a wide bow from the entering main street).

INSTANT STOP and I FLEW over the back of that f...ing thing.

In that moment I felt surprise, and anger, for being so stupid, but also thought in ultrafast-forward about anything I could think of to dampen the crash.

Which was to spread the energy of impact as much as possible around my whole body, execpt my head, and separate like hell from my roadbike.

I actually managed that while doing a summersault, not by myself, been already catapulted into it, still attached to bike, but got free of the pedals, and managed to spread out my arms and legs while flying feet forward, and somehow stay oriented like that.

BAM! Hit the road with my back at least a dozen meters away from 'lift-off', could have been 20 to 25 meters also. Can't tell anymore.

Hands outstretched, palms flat down. Head UP, chin toward my breast. Soles of my shoes also flat down, legs slightly bent upwards at the knees.

OOOF! Couldn't breath for a while, that just didn't work anymore, even if I tried. That went on for about 30 seconds, then I managed to gasp, and then it was gone. It didn't hurt, I just couldn't.

My palms tingled. The soles of my feet too. Like hell. But only for about a minute or so. Then that was gone, too.

In utter incomprehension I sat up and checked my hands, arms, ribs, legs, head. Nothing. Everything still attached, not broken, no blood, while the chalk white faces from that 2CV emerged, running toward me, shocked.

I told them to get their damned 2cv out of the roundabout, to avoid another crash, grabbed my bike from the street where it lay a few meters away, and went to the sidewalk, still debating with the shocked people that I wouldn't need an ambulance, that nothing bad happened, and they could calm down now.

No torn clothes. Yay for Levis 501 and Nomex45p Bomber Jacket CWU!1!! But the roadbike was trash. Not even the frontwheel, as I'd have expected, but the whole frame and fork bent diagonally sideways in a hard to describe way.

Did walk the rest of the way home, after removing the saddle, very light bell with a nice ring, tachometer, its sensor, cable and fixings.

Sitting on a bench in a park next to a river, thinking: Insane, insane, this can't be, can't have happenend like that, can't can't...

Moving on, still a few kilometers to walk, through forest. Sun rises. Still thinking can't be, can't be, like in an endless loop.

Went to bed at about 6AM after checking for bruises, swelling but nothing to be seen or felt. Used the next day to get me another roadbike (used) for 2000 Deutsche Mark ;-)