Page 3 - 300 Watts FTP will get me....

17-07.-2007, 01:18 AM

#31

Eden

Registered User

Join Date: Mar 2005

Location: WA State

Posts: 1,271

Re: 300 Watts FTP will get me....

Quote:

Originally Posted by Alex Simmons

Fancy wheels and bike with a good position will shave off seconds per kilometre, which over a decent TT adds up quite quickly.

It's still not going to take you from a mediocre mid pack TT'er to being on top - ask me how I know.... seriously though. I'm small and light, more of a climber than a TT'er. I have a TT bike because its easier to not have to tear down my road bike a stage races. I have a HED disc and a HED Jett 60 because I was able to get them pretty cheap - yeah they are not the latest and greatest, so maybe I'd shave off a few more seconds if I spent a few $1000.... I'm sure they've improved my TT a bit, but not so much that I'm not still middle of the pack...

Last edited by Eden : 17-07.-2007 at 02:05 AM.

17-07.-2007, 03:06 AM

#32

rmur17

Registered User

Join Date: Oct 2004

Posts: 974

Re: 300 Watts FTP will get me....

Quote:

Originally Posted by vio765

i have done my share of TT's given the experience i have. this is my 3rd year of racing. i went from 185W and 174 pounds in my first TT to 225W and 156 pounds in my most current TT. relative to the time i invest, i am satisfied with my progress up to now. i plan on riding like a man posessed (courtesy: Phil Sherwin and the boys at Versus) in the next couple of seasons. here are two points i must address (briefly):

a.) TT's are unfair, due to who has the toys usually go faster (there are exceptions). but we all have the freedom to upgrade to that equipement. and all the aero toys are legal, so get those toys if you can. otherwise, choose another sport or deal with it. i, and many others, do.

b.)whether or not TT's are valid in upgrade points or helping with bike-handling skills is irrelevent in this thread.

now, to me, 300 watts seems like it would get me something faster than 55 minutes. i did the indiana state TT championships yesterday ( i got 3rd in the Cat4 at 1h3m45s). i ran into a guy who said he could push 375W. i saw his equipement and it was very aero stuff. but he clocked in at like 53 minutes. granted, that is very fast, but with 375 watts, i would expect more! recall my friend who can do a 52m TT at 325 watts. clearly, the 375W guy's position must be bad and my friend's position must be good. i would think that the extra 50 watts would be able to push through the wind despite the poor position on the bike. hmmmmm.

I answered your question above: all else being equal going from 225W to 300W on normal TT (flat-rolling) terrain will drop your time from 62min to 55-56 minutes. Now on a hillclimb, it'd drop a lot more!

For 'normal' terrain and TT speeds (40-45 kph) here's the formula:
t2 = t1 * (p2/p1)^(-0.37)

t1, p1 are known times and power
t2, p2 are projected time given estimated power

if you get up around Pro/pursuit speed the exponent ought to be a tad sharper. Much less than 40 kph and it ought to be blunter. That's why I gave a spread of one minute.

Comparing to other people's power/speed is really a mug's game. Even different tires can add up to ten's of seconds over 40k. Different aero drag factors can add up to minutes.

__________________
rmur

Last edited by rmur17 : 17-07.-2007 at 03:46 AM.

17-07.-2007, 03:18 AM

#33

Eden

Registered User

Join Date: Mar 2005

Location: WA State

Posts: 1,271

Re: 300 Watts FTP will get me....

Quote:

Originally Posted by rmur17

Even different tires can add up to ten's of seconds over 40k. Different aero drag factors can add up to minutes.

I think my husband can really relate to that - he can kick butt at the indoor computrainer TT's, but almost all, if not all of those guys can take him in the outside, real world. He's big and broad (6'3"/4" ish) and no matter how good his position is he needs to generate a lot more power to go through the air. Even though the computrainer tries to take into account some of those factors he still gets an advantage....

17-07.-2007, 04:18 AM

#34

rayhuang

Registered User

Join Date: Jul 2006

Location: Cleveland, Ohio

Posts: 524

Re: 300 Watts FTP will get me....

Quote:

Originally Posted by vio765

if i went to try a 40k TT at 300 watts, i would have to stop after about 4 minutes! i recently talked with our "local fastman" and he explained he could do a 40k TT at ~325 watts. i figure that i might be able to get up to about 300 watts in a year or two. he regularly does 52-53min 40k's. if that can be done at 325 Watts, what could 300 watts do? 54-55min?

FWIW-I am at 65 kilos, averaged 274 watts for 23.7 miles with a time of 52:59. If you use this average speed of 26.8 mph and extend it to 25 miles then its a time of 55:58 if my math is correct. I dont have my frontal area, etc. calculated, but seat of the pants tells me that if I went 15 watts higher the entire way thats 0.2 to 0.5mph depending on wind. So lets hit middle ground and say 15 more watts is worth 0.3mph, thats 55:21.
The way I estimated a 15 watt increase equals a 0.2 to 0.5 increase in mph was during a flat TT in which the wind was constant (first a tail then a headwind) and I would ocasionally kick it up 15 watts from ABOUT 280 to about 300 and thats the increase in speed it netted me.

Thats my non scientific estimate of time for a 40k at 300 watts and 65 kilos. It is also importat to understand this is with aero helmet, suit, shoe covers, wheels and bike. Of course this is just for me, but were close in weight if nothing else.

Edit:I realize my numbers are not exact so dont go berzerk!! Its just guesstimates!!

__________________
My Blog: http://raysracingadventures.blogspot.com/

Last edited by rayhuang : 17-07.-2007 at 04:28 AM.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode