Australian Cycling Forums - Bicycles Network Australia

I love seeing pro's data...it shows you what mere mortals most of us are .
Check out Ryan Baumann's power for the 40km TT...400w av at 73 kgs for a under 23 .
But check out the time differences between the riders...OK we all know aero matters...but still!.
http://www.saris.com/athletes/PermaLink ... 9cb4a.aspx

only 1200kj of work? Is that different from the energy burned? As in it is pure work to make the bike move, and there are other stuff that go into the total?

Good read!

thanks for the link TLL, interesting stuff

tripstobaltimore wrote:only 1200kj of work? Is that different from the energy burned? As in it is pure work to make the bike move, and there are other stuff that go into the total?

Good read!

Power 'expended' through the rear wheel hub. The rule of thumb is to multiply by 4 for food intake Kj, but that's assuming 25% efficiency which is higher than reality, most people would be closer to 20%.

961kJ for my 40km TT on Sunday (AT) 248W average.

i.e 961kJ / .22 (22% muscle efficiency guess) / 4.186 (kJ to calories) ~ 1043 Calories

So with that 1hr effort I get to eat a half-day extra worth of food

Since this is with a PT and we're looking at power after drive-train losses then you could bump that up another couple percent, but it's close enough.

40km in around 50 minutes - shat!

My commute is 20km and I can get that in under 45 minutes if I push like a nutter.

Need roids.

provoked wrote:40km in around 50 minutes - shat!

My commute is 20km and I can get that in under 45 minutes if I push like a nutter.

Need roids.

It was also a flat course - you'd be surprised how much faster you can average when you're not stopping all the time or going up hill. Still exteremely impressive....

Armstrong posted some twitter thing about a TT ride he did today in Hawaii.

14 miles in 18:30 at 56.4 km/h. TT bike with standard wheels, skin suit with a road helmet, another pro tri finished about 7-8 seconds back. They did make mention of a tailwind however I shudder to think how much wattage they must have been pushing.

Ryan Baumann is amazing!! he can crank out 707 watts without his heart even beating?? Miguel, move over

glad i saw this; i always thought of power as mechanical power, which had no corelation to the bike being used..

Wayfarer wrote:glad i saw this; i always thought of power as mechanical power, which had no corelation to the bike being used..

It is! Power is dependent on you - but speed is dependent on a whole host of things like weight, air resistance, rolling resistance, etc.

1q2w3e4r wrote:Armstrong posted some twitter thing about a TT ride he did today in Hawaii.

Hi

Details here.

Andrew

I thought an aero set up would make a big difference. I've taken my tt bike on our club rides for a bit of time in a tt position and when the pace picks up it is like cheating, the tt bike is soo much faster than normal roadies.

Interesting the bloke who generated the most power was on a road bike, I've heard that as you drop your upper body and close up the hip angle you lose power. The power lost must be more than compensated by the aero benefit.

provoked wrote: Need roids.

One of them all CF saddles should see you sorted

Parrott wrote:Interesting the bloke who generated the most power was on a road bike, I've heard that as you drop your upper body and close up the hip angle you lose power. The power lost must be more than compensated by the aero benefit.

Dont forget, however, that TT bikes have a different geometry altogether.

the middle of the saddle and th bottom bracket are often closer together, and you sit further forward on the seat, so the angle is reduced.

315W vs 470W for the same result, that's a massif difference . There's a web page somewhere that describes the difference in wattage, starting with a normal road bike sitting on top of the handlebars and then adjusts the wattage for each change until full TT aero is achieved. Anyone know where that page is?

Think it was on velonews.

Is this sort of what you were looking for? You would have to ask TLL where he got it from.

Wayfarer wrote: Dont forget, however, that TT bikes have a different geometry altogether.

the middle of the saddle and th bottom bracket are often closer together, and you sit further forward on the seat, so the angle is reduced.

The nose of the saddle must be 5cm or more behind the middle of the bottom bracket according to uci regulations. I have had my road bike set up like that also along with clip on aero bars. The tt bike still eats it easily. That bloke looks to be riding in a tri where you can have the seat as far forward as you like. Needs a lower frontal position too by the looks .

Should be some cheap 2010 Specialized Team TT bikes going soon .
Sure I could get away with running one at a local TT .