General Cycling Discussion - What's your fastest speed on a Downhill

How fast can you go on a downhill stretch of road, my fastest downhill ride was at 70 k/hour, and you can just imagine these professional riders like they are doing like almost 90 k an hour during their decent at Mount Ventoux, at the Tour the France last year

96km/h/59.6mph - on knobbies.

:eek:

Are you CRAZY???? 56 mph????? And here I thought 30 mph was fast (although there are no real hills near me in Wisconsin).

Fast is fun...but if too fast, I want knee pads, elbow pads, butt pads, mouth guard-- in case of a crash/road rash!

WeeeeeooooooOOOOO!
sarah

Originally posted by Bbmoozer
Are you CRAZY???? 56 mph?????
59.6mph

It was a very quiet, very steep, very straight dead end street with a long flat runoff at the bottom. The perfect place for a speed test. The only real difficulty was riding up the thing beforehand.

I must go back there one day with my slicks on. I bet I could go over 100km/h. If only I could remember how to get there.

83kph/51.8mph on a downhill with two slight curves, braver men than me could go faster.

There is another hill that I have hit 80kph, I know someone that has reached 96kph on this hill but you need balls of solid steel, as the bottom is very bumpy (no road maintenance) and a blind right corner.
I usually hit 70kph/43mph on my way to work.

CHEERS.

Mark

53 mph going down the west side of going to the sun hy with a fullload. the road was curvy but tthat stretch was not bad and the speed just crept up then i saw the sign for the hair pin curve I almost went over the edge that day..

Only 37mph so far - there were these stupid metal boxes on wheels at the bottom of the hill :)

Richard

For me it's 46mph. I'm going to go back on a quiet Sunday morning and see what I can do.

I, too, think that 30 mph is fast (enough, anyway :) ). Which is why I will probably not be riding back down after I climb Ventoux.

Cheers...Gary

I hit 43 MPH while coasting down a hill. I probably could have gone faster, but my rims on that bike are not good and I was starting to feel the front tire bounce on the pavement. I need to get my good road bike out there sometime.

There is also a nice steep hill west of Nashville, Indiana that I have driven up and really want to ride down sometime. My truck had to downshift several times to make it up the hill. I almost rode down it the day I drove up the hill but I had just bought my road bike and did not have shoes for it.

According to my bike computer, I once hit 76MPH. At the time it registered that speed, I was playing with it and a paper clip at my desk.

65 mph. It was during RAGBRAI in 1998. I was in a paceline going down Pilot Mound Hill. For those that know what RAGBRAI is and know about the Pilot Mound Hill you know this is very possible on that hill. Especially since that part of the highway was redone prior to RAGBRAI that year. I hit this speed on my old road bike.

So far on my Vision R40 recumbent I have only managed to go as fast as 45 mph.

43 mph is my record. But I am a coward on descents. There is a local hill that I think I could hit about 45+ on with the right wind but I don't ride that one that often. I did Lizard Head Pass last year. I rode my brakes down the hill. Most of the people in the group hit well over 40 but I did not like the traffic and the potential of rocks and debris in the road. I talked to a local and he said he tried to get no higher than 40 mph on that hill - pretty much for the same reason. Having a wipe out at 40+ is not fun to contemplate much less actually have.

60 KPH on a department store bike.

I had to pedal of course since that thing has a terminal velocity of about 45 KPH.

I regularly hit over 50 mph on a local sweeping downhill and have gone 55+ mph (88kph) on that hill. Did a trip in the Green Mountains of Vermont and hit 60 mph on a long downhill.

Say your prayers before you fly. Speed is fun, fun, fun, but can be fatal if not careful.

48 mph downhill. but the real question is: how fast can you go on the flats? did 38mph with a 15-18 mph wind with me. Although when you think about it, anyone can hop on a bike and build up speed on a downhill. the thing that separates us from the rest is your max speed while you are going uphill, with a 15 mph headwind, on a crappy potholed road in a drizzle. now that is a topic.

36.5 mph, that's flying (for me)

There are no hills in texas :roflmao:
but I did once get up to 15 mph on my driveway!

Marty

38 mph on a straight downhill. Faster than that is a little scary. :eek:

Originally posted by lotek
There are no hills in texas :roflmao:
but I did once get up to 15 mph on my driveway!
lotek
Marty
Lotek youre flying I have to talk to you how you do it, have to know your secret man, I really need that kind of acceleration, I am not trying to pull your leg but I am really interested in the technique, I can use that

Did 43 mph on a fully loaded (panniers/tent/stove etc) moutain bike with semi slicks in France last summer.

Also clocked over 50 mph on a 3 geared Sturmey Archer Raleigh Shopper with 20" wheels aged about 15 in the mid 1970's in Greenwich Park (500' decent in about 1,500 feet), so to steep to ride up.

Can only say the speed was over 50 mph as too many tears in my eyes to read the speedo above 50 mph

I also crashed the same bike at about 40 mph, and still have the bone chips in my elbow to prove it.

"Lotek youre flying I have to talk to you how you do it, have to know your secret man, I really need that kind of acceleration, I am not trying to pull your leg but I am really interested in the technique, I can use that"



If I was a Texas oil baron, I could also manage 15 mph within the first 200 meters of my driveway, and have the chauffer pick me up in the Rolls Royce at the end of the drive. I live in London and very proud of the fact that my 'driveway' in actually longer than my bike (just).

The world speed record for a human powered viechle is on a recumbent bike with an aerodynamic shell.

I believe it was 115 MPH on a flat road.

Originally posted by kobyj

According to my bike computer, I once hit 76MPH. At the time it registered that speed, I was playing with it and a paper clip at my desk.

Hot Dang! Desk racing at its best! :D

56 mph, on a fairly mild downhill with a tailwind on our tandem.

Originally posted by Amir R. Pakdel
The world speed record for a human powered viechle is on a recumbent bike with an aerodynamic shell.

I believe it was 115 MPH on a flat road.
That'd be the motor paced record would it not? The unassisted record over 200m (flying start) is a smidge over 80mph set last October by Sam Whittingham. (http://legslarry.crosswinds.net/tech/MLS.htm)

Texan to city type: "My ranch is so big, it takes me three days to drive from side to side."

City type's reply: "I had a car like that once."

70kph last year at Willingen Bike Festival. Not that fast but it was through a river of mud :eek: .

Did anyone see the crash a few days ago when that crazy Frenchman attempted the record? He came down a hill doing over 100kph (62mph) when his headtube snapped. His bike then snapped in two and he was flung 300 metres down the hill. They showed a picture of his crumpled body afterwards. It looked worse than it was, because he got up again. :eek:

I really need that kind of acceleration
Orguasch, Its easy, the driveway has about a 30 degree pitch!
That and riding on Rollers has necessitated my being able
to get up to speed really fast, or I fall REALLY fast! :lol:

Marty

I once reached 56 m.p.h. on a long, long downhill. I was riding with loaded panniers on a bicycle that was not designed to carry weight (racing bike with thin-wall top tube). At this speed shimmy came on sudden and violent and nearly caused me to loose control of the bike. Now I understand why real touring bikes have super-strong top tubes !

Got up to 48mph/77kph going down a nice, long, smooth descent from Deadman's Summit on Hiway 395 when the Automatic Governor kicked in (translation: stoker loudly vocalizing about the drag brake). A little later another tandem passed us at about 10mph faster.

Originally posted by UncaStuart
Got up to 48mph/77kph going down a nice, long, smooth descent from Deadman's Summit on Hiway 395 when the Automatic Governor kicked in (translation: stoker loudly vocalizing about the drag brake). A little later another tandem passed us at about 10mph faster.

The great thing about coming down that hill is the low wind resistance that goes with 8000 feet elevation. OTOH, going up is a bear.

On our tandem, the stoker has control of the rear drum via a racheting thumbshifter. Sometimes she doesn't wait to be asked, instead says "Brake is going on NOW!" I've got to fix that.

Jim

41 m/ph today going down the Rickenbaker Causeway on Key Biscayne.

On a mountain bike.
Dave

About 48, but that was on a downhill with curves...S-curves! About 17% grade. I don't know what I could do on a straight downhill...

54mph on the road down from Mt. Charleston, just north of Las Vegas.

(I'd recommend that road, for anyone who wants to try going FAST! At the top of the mountain, it's twisty-turny mountain road, but the bottom 10 miles or so are 2 very, very long straight stretches, with a fairly gentle slope. Whoa, doggies! My AVERAGE speed, for about 12 miles, was 40+mph. No pedaling, just trying to hold 'er steady.)

I hit a tree stump with my pedal at 27mph on a single track not too long after I got the bike. That was the fastest I had gone up until that time. After replacing my crank arm my computer was never quite the same, no matter how hard I tried it wouldn't register anything over a couple mph. That reminds me, I'm going to start a thread and see what you guys like for computers.:)

50-52 MPH on a long steep hill. A car was following me, and when we got to the bottom, he said I was going just over 50. I didn't have a computer on my bike at the time.

Note: Some of the cheaper computers state that speed calc is not reliable over 45 MPH. Has anyone else seen this?

I strapped a GPS to a friends back (he is a state champion downhill racer) and he hit 66 mph. We were both so surprised we tested the GPS in the car to make sure it was working properly. Now you know why downhill racers wear that goofy body armor (I am a XC guy and roady).

38, and that was on my old mtb wif nobblies on road, and hill wasnt that steep.. i see ill have to practice some

I don't know, but it was TOO FAST. once, on a very steep grade on a walmart bike, and today, with some XC'ers I went out with that are WAY better than me. I couldn't even walk down those hills.

The idea of a front tire blowout at high speed on a bike going downhill is about the scariest mental cycling image I've ever had.

It keeps me from pushing it going downhill. I thin I may have gotten up around 38 a couple of times, but even that was sufficient to make my HRM start beeping at me.

RichC

Originally posted by Rich Clark
The idea of a front tire blowout at high speed on a bike going downhill is about the scariest mental cycling image I've ever had.
Yeah, my speed on a downhill has a reverse correlation to the activity of my imagination on any particular day!

The idea of a front tire blowout at high speed on a bike going downhill is about the scariest mental cycling image I've ever had.

A tyre blowout is a scary thought. In reality the chances of a blowout are pretty thin unless the roads are full of debris, which is rare for fast downhill roads, most of these tend to be in the quieter parts of towns, back roads, country roads etc. The majority of debris on roads is usually in the city where traffic accidents happen. Of course a blowout on a corner is going to hurt but that is just part of cycling, it happens when it happens. Cycling is a dangerous sport.

I don't want to sound complacent, having a blowout can cause a crash but not always, if we were to worry about crashing we would not ride any where.
I am no hero, I will go fast on the straight but take the corners about 10-20% slower than most roadies, as I am always thinking about the possibility of a tyre blowout, or underestimating a corner. That's probably why don't race either.

Everything in life is a calculated risk.

CHEERS.

Mark

Originally posted by Dutchy


Everything in life is a calculated risk.



Interesting thought. . . Might have to use that.

Hi everyone, this is my first post and hope it won't be my last.

My fastest speed is 42mph on a MTB with full tread going down a forestry road, but what I'd like to know is am I the only person who's eyes water big time when going fast downhill,

My eyes water so bad it difficult to see and at that speed it no fun (okay it is fun, bloody dangerous, but fun.)

Originally posted by Ouch !
Hi everyone, this is my first post and hope it won't be my last.

My fastest speed is 42mph on a MTB with full tread going down a forestry road, but what I'd like to know is am I the only person who's eyes water big time when going fast downhill,

My eyes water so bad it difficult to see and at that speed it no fun (okay it is fun, bloody dangerous, but fun.)

Welcome to the forums, and nope, my eyes water above 30 mph as well :)

Richard

I've never had a speedometer on a bicycle---so couldn't really say how fast I've gotten it up to.

I have done 110mph(youthfull indescretion) on a motorcycle--anything I've done on a bicycle pales in comparison.

And NO---you won't catch me pushing those kind of speeds anymore.

I don't know at what speed my eyes start to water: I can't read the computer.

Originally posted by Dutchy

Everything in life is a calculated risk.


Yes, and I calculate that I'd rather not have a front tire blowout at 40mph.

I don't know if going that fast actually increases the chances of a blowout, other than just making it harder to dodge obstructions, but that's not my concern.

My concern is that the seriousness of the injury if I get a blowout while flying downhill is likely to be much more severe than if I get a blowout going 20mph on the flat.

I don't race, either. Except city buses.

RichC

Originally posted by Allister
I don't know at what speed my eyes start to water: I can't read the computer.

:lol:

Nice one

I don't know if going that fast actually increases the chances of a blowout

I would assume that speed is not the cause of blowouts. If the tyres are in good condition, and pumped up to the recommended pressure, rim tape fitted correctly etc. the chances of a blowout don't increase with speed.

The majority of punctures are just that, a puncture, an object has caused the tyre to deflate. The only time I think speed could cause a blowout is descending on a day with temperatures in the 40ºC range (100F+). I have come down some winding roads on HOT days, with lots of braking at the bottom of the hill as the road turns into the metro area. I got a flat, and when I tried to touch the rim it was too hot to touch.

So in theory with the heat between the road, tyre, rim and constant braking there could be a serious heat build up that could cause a tyre to blow.

Just do what I do.... Don't think about it. It's the same as being hit by a car, it is out of our control.

CHEERS.

Mark