LarrySellerz

Hey guys, I test rode my brothers new bike yesterday and bombed down a hill. I was wearing a helmet so I felt confident to just take the bike to close to its maximum speed, I didn't record it on Strava but ive never gone that fast and was probably approaching 40 mph. It was low-key sketchy as ****, normally I max out at around 33 and even that seems sketchy. I crashed hard on a descent 5 years ago and I think im subconsciously afraid now. How fast do you descend before you start feeling unsafe? Are you more likely to go full send if youre wearing a helmet?

datlas 

I get nervous above 40. I once hit 50 drafting a tandem.

Everyone has their own comfort level, also depends on road conditions and familiarity with the road. If sketchy I will take it slower.

LarrySellerz

Lol drafting at 40+ mph seems ******g nuts, at least you did it once though!

cxwrench

87mph...or something.

ericcox

It really depends on the hill, the road conditions, and the bike. On a fairly straight descent I ride regularly, 40+ is no big deal. On another descent with bad pavement and a blind corner, I keep it closer to 30. If I didn't have to worry about oncoming traffic, I would push much higher than that. Way back when I first started riding in VA, the fastest I ever went was about 50. I never started getting nervous until I had to brake :-).

HTupolev

Depends on the circumstances. On quality road with good visibility for all plausible sorts of oncoming hazards, I'm not sure that there's much of a limit: I got up to 57mph once, and it wasn't especially scary. But something is hindering visibility of the road surface, or if there's a chance of stuff like unseen cross-traffic blundering into the road, I might limit myself to slower speeds. Similarly, sometimes a road just can't be descended very fast for handling reasons. On the double-track gravel roads in the foothills, the fastest I've ever gone is a bit over 40mph, and I only occasionally even exceed 30mph; on yesterday's mixed-surface ride, the fastest I reached off the pavement was only about 27mph.

rubiksoval

I go shoulder to shoulder at 35+ on the flats in sprints, so nothing in the 30s really makes me take notice unless it's wet and/or a dangerous road.

I've hit 62 in a race, and over 50 many times on my own, but that's about it. If I didn't look at the speedometer, I wouldn't really be able to tell much past 50. At that point it all seems pretty quick.

With or without a helmet doesn't really matter at 40+. You hit something head on and you're pretty much done. It's not something you can think about, really.

HTupolev

I'm not sure, because I basically always wear a helmet. Seems like going helmet-free would just be slowing me down for no reason.

LarrySellerz

Yeah I commute without a helmet and I feel like going mid 30s on the hills I know like the back of my hand is safe, im trying to up my pace on them

rubiksoval

Why? Trying to go faster on downhills on a commute just sounds pointless.

bruce19

I once did 53 mph. But, I am older and wiser (I tell myself) so I don't do anything like that anymore.

Koyote

You can search this. A thread like this pops up around here every now and then.

My max speed was 75.7 mph on a steep canyon descent in Colorado during a road race.

LarrySellerz

The more speed I can build on the downhills the faster I can maintain speed on the flats/uphills right after

LarrySellerz

wow that's insane

Koyote

Hey, it allowed me to claw my way up to 57th place! Totally worth risking my life.

DaveSSS 

I set a new record for me of 56 mph heading north out of horsetooth lake toward Bellevue on Friday. I have at least one hill on every one of my routes where I go over 50, so it's a regular thing for me.

rubiksoval

indyfabz

Low 30s is at the top of my comfort zone, in part because I take blood thinners, so crashing at speed poses additional risk. I did do 48.5 on a fully loaded touring bike coming into Ticonderoga, NY. I also hit 43 five years ago on a descent in Montana. Good road surface, good shoulder, good sight lines and no traffic.

LarrySellerz

Lmao I feel you, you only live once

WhyFi

If there aren't any curves, I grab two handfuls of copper, get aero and let it happen.

tomato coupe

Where was that?

scottfsmith

My eyes become a limiting factor at some point. I hit 40 on a hill today and they were tearing up too much and I had to slow down. I have prescription eyeglasses but I'm starting to see why all the pros are wearing those face wraps.

The road itself was straight, wide, perfectly paved, no cars etc so no real reason to slow down otherwise. The gyroscopic forces get higher the faster you go so it gets progressively harder to wipe out.. unless an obstacle suddenly presents itself.

Koyote

If I am reading Dave correctly, it was on the same descent: coming North off the last dam along the East side of Horsetooth Reservoir, heading down to Bellevue. This was in the Fort Collins Road Race, around 2008 I think. I pedaled very hard off the top, as long as I could, then pedaled some more about 1/3 of the way down where the road grade levels off just slightly, if I recall correctly; then I tucked very deep. Was trying to chase onto a group.

And as Dave says, that area has plenty of steep descents, and many of then are long, straight, and smooth. Coming off the top of Rist Canyon into Buckhorn I could always hit 62 mph without trying too hard.

deacon mark

I live in Illinois flat as they come so on biggest descends around here 40 is pushing the limit. In the few times I have been in hilly places I hit 43.5 and thought that was pretty much my limit. If conditions and roads great I could see 50 but not above that for sure. I once biked in mountains in Montana but no really long stretches that would seem to allow the speeds some are talking about. I would like to see the Strava data on the 75 mph hit by someone. I think every once I a while a pro tour ride gets near that but no often and they are pros. Over time one can get better and use to the speed but for me it takes time given where I live.

genejockey 

I have hit 45 mph, and routinely exceed 40, but usually only for a few brief shining moments. The hills here are either not steep enough, or not long enough, or if they're steep enough and long enough they're not straight enough. Even the spot where I used to hit 40 all the time changed - there's a traffic light at the bottom that the City in its infinite wisdom set to almost invariably be red when I get there and stay red for a ridiculously long time.