TT question...

Amprodude

Besides having the legs and engine in you how many seconds would you gain by having a aero helmet on when doing a TT like 10km? Is it possible to gain 10 secs?

How many seconds is it possible to gain with a disc wheel?

Lusk_Doyle

Beasty is the man to answer this one. The difference those two pieces of kit make is very significant. Throw in a skin suit and shoe covers and you're away!

ednwireland

this http://cyclingtips.com.au/2010/04/biggest-bang-for-your-buck-in-time-trial-equipment/ posted in this thread http://www.boards.ie/vbulletin/showthread.php?t=2057161171&page=2

Chips Lovell

The answer is "it depends". Wind resistance increases exponentially rather than linearly, so the faster you're going, the more you will benefit from aerodynamic equipment. In other words, something that saves you 1 percent at 30kph could save you 2 percent at 40kph, and so on.

Aerobars, followed by a TT helmet are usually regarded as the two first steps towards getting a more aero set-up, i.e., you'll get the greatest benefit from a small investment.

Inquitus

Overshoes are the best bang for buck no? Along with clip on aerobars.

Borderfox

You can work out a formula regarding price per gain. For me Tri bars are the start second would be a good fit on the bike regarding the change in position with tri bars on, next is a tt helmet along with a skin suit and overshoes.

Lumen

Vladimir Kurtains wrote: »

The answer is "it depends". Wind resistance increases exponentially rather than linearly, so the faster you're going, the more you will benefit from aerodynamic equipment. In other words, something that saves you 1 percent at 30kph could save you 2 percent at 40kph, and so on.

Nope.

If something reduces 1% of drag it will do so at any speed.

What changes is the relative contribution of aero drag vs rolling resistance and drivetrain losses.

Chips Lovell

I meant percentage of time rather than drag.

Lusk_Doyle

Lumen wrote: »

Nope.

If something reduces 1% of drag it will do so at any speed.

What changes is the relative contribution of aero drag vs rolling resistance and drivetrain losses.

Is that a breakfast roll on the ground in the above?

Lumen

Vladimir Kurtains wrote: »

I meant percentage of time rather than drag.

Ah.

Example from online calculator:

300W on drops gives 40kph, 40km TT takes 59.90 min.
300W on aerobats gives 43.4kph, 40km TT takes 55.33 min.
Difference in time: 4.57 min, or 7.6% of slower time.

400W on drops gives 44.53kph, 40km TT takes 53.89 min.
400W on aerobats gives 48.25kph, 40km TT takes 49.74 min.
Difference in time: 10.15 min, or 18.9% of slower time.

on_the_nickel

Lusk_Doyle wrote: »

Is that a breakfast roll on the ground in the above?

Swiss roll. Cancellara came up with the graph.