Fastest Speed for a training session

[velomanct]

How about the sprints in a pro-race like Giro Italia/Tour de France and other World Cup races ?
I red somewhere tha Alessandro Petacchi had an end-speed of 71 km/h in a winning sprint in the Giro. ...........
that would be 53x11 with about ONLY 115 rpm !


does anyone know what top-amateurs usualy reach in winning sprints ?
cu

Given a flat road with no wind, at the end of a road race, a top amateur field, the top speed in the sprint would be very close to what the pros are doing. Maybe 41-43mph. The biggest difference between top amateurs and pros is that the pros have big leadouts, like Petacchi's team. Pro road sprinters are not a whole lot more power than good amateur sprinters. I know some cat 2s who can do more power than Petacchi in a sprint. But Petacchi has the superior aerobic engine to get him to the finishline after a brutal 120miles and still be strong. His threshold power is 400watts, that's not a whole lot less than the good GC guys in the big tours.

BTW, my most efficient cadence when sprinting out of the saddle on a flat road is 115rpms too.

 

[velomanct]

Around Boulder, Colorado here there are lots of STEEP hills. I was shooting the breeze with a cop a few months ago and started talking about bombing down some of the hills. I asked him if he'd give me a ticket for going 50-55 MPH down a hill that I often ride on - I go that speed with some heavy braking... The posted speed limit is 35. He said he doesn't mess with average bikers but he's given a few tickets for going 70+ MPH.

Anything past about 45-50 is just a question of how steep the hill is more than RPM's - oh yeah and the inverse relationship of testosterone and brains. Spinning as fast as a trackie on a steep descent makes you unstable IMHO. I've had too many nasty crashes to have the courage left to get into a full aero tuck with my chest on the bars now that my teens and 20's are behind me.

You are right about being unstable at high rpms. When I was spinning my butt off at 200rpms, at 70mph behind the suv I was drafting, I was getting bounced around by the cracks in the pavement. You can really launch yourself if you are doing crazy high rpms on a rough road, especially above 50mph. I caught air on a different road at 55mph. Not a lot, but I was airborne.

BTW, I was 17 when I did the 70mph stunt, that was two years. I know given the right conditions and gearing(56x11), I could do 80mph, but it's just too dangerous. I would barely make the curve at the bottom of the hill. And it's a 45mph zone. here's a topo map of it http://www.topozone.com/map.asp?z=18&n=4603097.00007487&e=671957.000025939&datum=nad83




It sounds like you can really get cranking on those mtns in CO. (it helps to have less air density). Imagine if you drafted a vehicle down one of those straight steep hills? That would be some insane speed.

 

[Rollo]

80km/h on a long straight downhill drafting behind a TRUCK. It has to be tried they just suck you along i drafted behind it then had to pull out and overtake it on the corner because it was too slow.

Rollo

 

[closesupport]

80km/h on a long straight downhill drafting behind a TRUCK. It has to be tried they just suck you along i drafted behind it then had to pull out and overtake it on the corner because it was too slow.

Rollo

i know i've done 40+ behind wagons and pedalling does seem pretty effortless, once your upto speed with the wagon, then its ease from there, but the hard part is getting up to speed and sitting in long enough to feel its effects, aslong as you can sit in close enough it will pull suck you along. but you do have to be dangerously close for it to suck you along. imagine building an imaginary equal triangle from the back of a vehicle, sitting within that triangle, you'll benefit.

 

[velomanct]

i know i've done 40+ behind wagons and pedalling does seem pretty effortless, once your upto speed with the wagon, then its ease from there, but the hard part is getting up to speed and sitting in long enough to feel its effects, aslong as you can sit in close enough it will pull suck you along. but you do have to be dangerously close for it to suck you along. imagine building an imaginary equal triangle from the back of a vehicle, sitting within that triangle, you'll benefit.

That's why the stunt in Breaking away was not all that impossible. Athough I doubt he held 50-60mph for an hour. Even with a 50x13 you can get up to 50mph in that situation.

 

[guidebar]

My fastest all time speed is 89km/h down part of the worlds course in Hamilton,Ontario where I live and I haven't been able to crest over it since.(must have been a once in a while incredibly good day)All I have to say is MAN it was EXHILIRITING!
My all time fastest out of the saddle on a flat is 58km/h and that hurt like a mother!
Great thread.

 

[philhudson]

my 2nd time on a road bike i was doing 40 down a hill, slammed on the front brake and endoed it (back wheel of the ground) and managed to stay on!

 

[closesupport]

my 2nd time on a road bike i was doing 40 down a hill, slammed on the front brake and endoed it (back wheel of the ground) and managed to stay on!

have you ever tryed to keep the rear wheel off the floor, its a cracking posing technique when there are loads of female college students, well unless it goes tits up, probably best suited to mtb however.

 

[philhudson]

lol! yeah thats what happened....i was lucky i didnt go over the handel bars....!

 

[li0scc0]

any ever get pulled over on bicycle for any reason?

Yes but by a female officer

 

[li0scc0]

I've done 79kmph down a hill.

How do you draft behind a car downhill???
What if you hit a pothole or something. LOL only for the fearless.

Yes, hitting a pothole at 79 km/hr is dangerous....so is clipping wheels at 85 km/hr. Took 17 years to get on a bike again.

 

[closesupport]

Yes but by a female officer

never been pulled over, but have been told to slow it down a little.

but as for your endo's my old training partner used to do them all the time when approaching traffic lights, he perfected this skill on his TZR, and it was a real head turner seeing him ride upto the traffic lights on the front wheel either on the motorbike or on the mtb. thats where i picked it up from, wouldn't try it on my roadbike with claets however just incase things did go tits up...

 

[Tri-Dude]

I know I'm only a new boy to bikes but you guys are so slow, my highest speed on a bike was 187.64mph into a slight head wind over a quarter mile.





I was on motorbike (ZZR 1100) drag racing, at the time, but let me tell you it is very, very windy if you stick you head up at that speed!



But on a cycle I thought my fastest of 48mph downhill, was pretty good until I read the speeds you guys are hitting, you must be supermen.

 

[closesupport]

I know I'm only a new boy to bikes but you guys are so slow, my highest speed on a bike was 187.64mph into a slight head wind over a quarter mile.





I was on motorbike (ZZR 1100) drag racing, at the time, but let me tell you it is very, very windy if you stick you head up at that speed!



But on a cycle I thought my fastest of 48mph downhill, was pretty good until I read the speeds you guys are hitting, you must be supermen.

NOT SUPERMAN JUST TRAINIED TO DO IT, AND I HAVE DONE 110MPH 2'S UP ON THE TZR 115MPH 2'S UP WITH THE POWERVALVE AND COMPUTER OPEN TO FULL.

THE FASTEST I HAVE DONE IS 145'ishMPH ON A ZX NINJA, IT WOULD DO MORE BUT MY BALLS WENT

SO I'M MORE THAN HAPPY WITH MY 65MPH PEDALLING "SINCE MY **** GOES AND MY BALLS DROP AT DOUBLE THAT" I THINK YOUR EITHER VERY BRAVE OR VERY STUPID, LIKE THOSE DOWNHILL MOUNTAIN BIKERS....

 

[Tri-Dude]

NOT SUPERMAN JUST TRAINIED TO DO IT, AND I HAVE DONE 110MPH 2'S UP ON THE TZR 115MPH 2'S UP WITH THE POWERVALVE AND COMPUTER OPEN TO FULL.

THE FASTEST I HAVE DONE IS 145'ishMPH ON A ZX NINJA, IT WOULD DO MORE BUT MY BALLS WENT

SO I'M MORE THAN HAPPY WITH MY 65MPH PEDALLING "SINCE MY **** GOES AND MY BALLS DROP AT DOUBLE THAT" I THINK YOUR EITHER VERY BRAVE OR VERY STUPID, LIKE THOSE DOWNHILL MOUNTAIN BIKERS....

Used to have YVPS 350, of the smell of 2 stroke oil, did over 150MPH on it (clock ran out)

But now I'm sticking to cycling slower but maybe not safer considering some of the drivers out there.

 

[velomanct]

But on a cycle I thought my fastest of 48mph downhill, was pretty good until I read the speeds you guys are hitting, you must be supermen.


Nope, you just need to the right combination of downhill, leg speed, and balls.

 

[962817]

The fastest I've ever hit is 50.50 down a certain hill on my Saturday morning ride. Routinely, I hit 49.9 on this hill while in a tuck without peddling, but lots of praying.

 

[Fixey]

The fastest I've ever hit is 50.50 down a certain hill on my Saturday morning ride. Routinely, I hit 49.9 on this hill while in a tuck without peddling, but lots of praying.

Weight is also a factor.... I weigh over 100kg (130kg at times) and loose most guys going down hill (or catch them up after they dropped me going up the previous hill ) My all time top speed is about 110kph down a big hill. Funny enough apart from the kick at the top I don't pedal down hill, I put my groin just behind my bars and rest my torso on the Stem/bars, my head hangs out over the front wheel, looks hilarious and is as unstable as hell, but geeees its a quick way to descend.

 

[pod]

Weight is also a factor.... I weigh over 100kg (130kg at times) and loose most guys going down hill (or catch them up after they dropped me going up the previous hill ) My all time top speed is about 110kph down a big hill. Funny enough apart from the kick at the top I don't pedal down hill, I put my groin just behind my bars and rest my torso on the Stem/bars, my head hangs out over the front wheel, looks hilarious and is as unstable as hell, but geeees its a quick way to descend.

Weight isn't a factor at all. A light object has exactly the same acceleration due to gravity as a heavy one. Wind drag may vary slightly between a heavy person and a light one but will be affected more by position on the bike.

Speaking of bike position, I'd hate to see what would happen if you had to break hard.

 

[daniels]

Weight isn't a factor at all. A light object has exactly the same acceleration due to gravity as a heavy one. Wind drag may vary slightly between a heavy person and a light one but will be affected more by position on the bike.
.

As far as I know, for two riders with exactly the same wind drag, the heavier one will descend faster. Your terminal velocity, which is the speed you can reach while descending, is determined by your weight.

If you want the physics it is basically this:

When you hit your terminal velocity, your downwards force, dependent on mass, is equal to your drag, which depends on your speed squared. The other dependencies are constant and include acceleration due to gravity, frontal surface area, drag coefficient and air density.

So we can basically write this as: speed squared depends on mass.

Or: speed depends on the square root of mass

Or just have a look at http://analyticcycling.com/DiffEqMotionTerminalVelocitySlope_Page.html