TT Profile #'s. Do they look correct?

[Chainring]

I'm a newbie with this thing and i want it to be a useful tool. I did 10 coast downs today followed by a cal ride of about 5 miles. i did this to establish a "Race" profile for time trialing, so I had on my skin suit and aero helmet. Was carrying no tool, etc... Here are the numbers I got for the profile

0.147 Aero
0.599 Wind Scaling
0.246 CdA
5.553 Fric
-0.1 Riding Tilt
0.0047 Crr
208 Total Weight

Do these seem accurate? Similar to any other rider my size? It has been unusually windy and cool so far this spring, so it has been difficult fiding the optimal day. Also, the place where I did this ride was at the state park where I do the time trial series and the roads are a bit rough in spots. Not sure how much that matters. Also... I run 700/20 tires at 130psi.

Much appreciated,
~Steve

[racerfern]

Without seeing how you look on a bike it's hard to really judge. However, your setup and numbers seem to be spot on for the "average" TT. I suppose you could say your CdA is a tad low for a guy who weighs about 185lb, but I wouldn't fret over it.

Consistency is the key so Run, er Ride with it!

Good luck in your TT series.

[rruff]

Like Fernando said, your CdA could be a little low, but the rest looks fine. If you are extremely aero the CdA might be fine too.

[Morocco Mole]

Where is your iBike Mounted, are you using the RWS? Any pics, I'm always interested in seeing others TT Setups.

Cheers
Jim

[Chainring]

Thanks for the replies. I think I'm pretty darn aero, but I'm not running a disc in the rear or deep dish in the front. Just running the 40mm aero wheels you see in the picture. I'm racing a TT tonight, so I'm going to run this profile and see what the numbers look like when I'm done.

Here are a few pic's of the way I have it setup on my bike. Mounted with a wireless stem mount (using Garmin HR/Cad/Speed). Note I don't have the rubber piece in the air port at the moment, hence why I'm holding the tube for the pictures.

ibike 2.jpg (146.66 KiB) Viewed 20942 times

ibike 1.jpg (140.93 KiB) Viewed 20946 times

ibike 3.jpg (122.82 KiB) Viewed 20943 times

[SHPTri]

I'm going to be mounting my iAero to my TT bike with Zipp aero bars. Is this a good mounting option? It seem like it really leaves the port in a good location where your hands can't interfere. But will an aero bottle mounted between the aerobars mess it up by "deflecting" wind into it?

[Chainring]

I just stumbled onto this article. Good read, but by looking at the numbers they had with a full TT setup, I certainly think my CdA looks too low. Should I edit my profile to a higher CdA, and if so, what would anyone recommend I use? My last TT race I ran with the "Fast Start" numbers and it gave me a CdA of 0.273. Seems more realistic. But, should I even mess with it or maybe scrap this profile I created and go "Fast Start" again tonight and try another cal test another day?

http://www.cyclingnews.com/features/how-aero-is-aero

[racerfern]

I'm going to be mounting my iAero to my TT bike with Zipp aero bars. Is this a good mounting option? It seem like it really leaves the port in a good location where your hands can't interfere. But will an aero bottle mounted between the aerobars mess it up by "deflecting" wind into it?

The aero bottle will not mess things up as long as you do your calride and coastdowns with the aero bottle in place.

[racerfern]

[quote="Chainring"]I just stumbled onto this article. Good read, but by looking at the numbers they had with a full TT setup, I certainly think my CdA looks too low. Should I edit my profile to a higher CdA, and if so, what would anyone recommend I use? My last TT race I ran with the "Fast Start" numbers and it gave me a CdA of 0.273. Seems more realistic. But, should I even mess with it or maybe scrap this profile I created and go "Fast Start" again tonight and try another cal test another day?quote]

Why not switch to the FAST START profile and compare your numbers after the race with some websites that will give you good estimates of power required to complete X distance in Y time. You can also compare your numbers to others with similar setups and finish times (though this has a lot of varibles). Then if necessary tweak your profile or just switch to the original one.

[Chainring]

I just stumbled onto this article. Good read, but by looking at the numbers they had with a full TT setup, I certainly think my CdA looks too low. Should I edit my profile to a higher CdA, and if so, what would anyone recommend I use? My last TT race I ran with the "Fast Start" numbers and it gave me a CdA of 0.273. Seems more realistic. But, should I even mess with it or maybe scrap this profile I created and go "Fast Start" again tonight and try another cal test another day?quote]

Why not switch to the FAST START profile and compare your numbers after the race with some websites that will give you good estimates of power required to complete X distance in Y time. You can also compare your numbers to others with similar setups and finish times (though this has a lot of varibles). Then if necessary tweak your profile or just switch to the original one.

If I already have the profile in the iBike, if I switch to "Fast Start" manually in the set up screens will that override the profile that was uploaded from the computer?

Also, why do you think the profile would be off? I did 10 coast downs and a 5 mile Cal ride (more than what is necessary in order to get more data). I love this thing on the trainer b/c it's great for intervals, etc... but I need it to be more accurate outdoors to see my progress, not to mention that now that the weather is getting nicer I hope to be on the trainer a whole lot less.

[racerfern]

You'll find the most important part of training with power is consistency. Whether you produce 250w or 260w for a TT doesn't matter. After all, it's the time needed to complete the course. One thing (increased power) will allow you to complete the course quicker and the second thing being more aero will allow you to complete the course in the same time with less wattage. So you'll be able to do a quicker time with the same effort.

Pick a profile, and just use it. As you get stronger you'll see your wattage increase and your TT times drop. As you make changes to your position or equipment you'll see that you might want to adjust your CdA. The proof will be in the pudding of the TT times.

My training rides includes some climbs that I know the exact time needed to complete at a given wattage. I also do some runs on flats that with changes in positioning or a loss of 4-5 pounds makes a difference how far 230 watts takes me. It won't take you long to set yardsticks to measure yourself by.