Bike Forums

Bike Forums (https://www.bikeforums.net/forum.php)
-   "The 33"-Road Bike Racing (https://www.bikeforums.net/33-road-bike-racing/)
-   -   Updated my ewang chart (https://www.bikeforums.net/33-road-bike-racing/454503-updated-my-ewang-chart.html)

umd 08-15-08 12:46 PM

Updated my ewang chart
 
Ok, so I still don't have my power meter, but I calculated and estimated my power from my uphill TT PR yesterday. The power analysis is from the GPS2PowerTrack plugin for SportTracks. It is supposed to be fairly accurate for a pure climb like this, at least over longer time periods. Some of the smaller wobbles probably can’t be trusted. I will say that I was nearly neck-and-neck with one of my cat 2 teammates up the climb until he pulled away from me about halfway up. He had a powertap and adjusting for our weight difference, had similar numbers.

So using the power track data in SportTracks, I determined my power over various time frames and mapped them to the “ewang” chart that’s been floating around. I used the 30 second power as the 1 minute power because we hammered the start but eased up before we had been going for a minute. I could have maintained that power (and probably more) for at least a minute, but I wouldn’t have done very well on the whole climb. I also estimated 20 min power based on my relatively steady power output for the last 5 minutes or so, assuming a slight drop. Of course I’m working off estimated numbers to begin with, so take everything with a huge grain of salt. I don't have the resolution in the estimates nor did I do the kind of efford needed to even begin to pretend to analyze 5s power, but based on some vague notions I would put it around 14 W/kg)

30 second Power/Weight: 7.2 W/kg
1 minute Power/Weight: 6.6 W/kg
5 minute Power/Weight: 5.4 W/kg
15 minute Power/Weight: 4.8 W/kg
20 minute Power/Weight: 4.7 W/kg (estimated)

http://www.photoscene.com/kimandsteve/images/3439.png

Snuffleupagus 08-15-08 01:36 PM

Yeah...

Without a power meter this is worth nothing. Sorry.

umd 08-15-08 01:44 PM

I don't believe it is very accurate but I don't think you can say it is worth nothing. It was a significant grade and it is fairly straigtforward to calculate power based on weight grade and speed, and comparison to the other rider with a power meter beared similar results. Use whatever method of determining power you want, but 1200 feet gained on an 8% grade in 15:43 is not an insignificant amount of power.

Snuffleupagus 08-15-08 01:53 PM

I'm not saying you're slow, I'm saying swaging numbers is essentially pointless.

umd 08-15-08 01:56 PM


Originally Posted by Snuffleupagus (Post 7279665)
I'm not saying you're slow, I'm saying swaging numbers is essentially pointless.

I suppose. But I think that the factors involved here are straightforward enough that the results would be that far off even if I had used a real power meter. The software takes windspeed, weight, rolling resistance, aero position, etc. into account. Next time I'll borrow someone's PowerTap if I still don't have my Quarq yet...

umd 08-15-08 01:58 PM

Procedural question, is everything supposed to be from the same effort? I mean, do you go all out at the start and then continue as hard as you can for 20min when you are testing this, or are you supposed to do an optimal effort for each time frame independently?

Snuffleupagus 08-15-08 02:06 PM

You should try to do a specific effort for each. Also, the last column isn't supposed to be 20 minutes, it is FT, aka 60 minutes or something like 85-95% of the 20min effort.

merckx89 08-15-08 02:07 PM

Different test for each time frame, preferable on different days to get a true number (i.e. totally recovered)

umd 08-15-08 02:08 PM


Originally Posted by merckx89 (Post 7279758)
Different test for each time frame, preferable on different days to get a true number (i.e. totally recovered)

Yeah I figured. I'm really anxious to get my power meter, so I'm doing stupid stuff like this. I'd much rather use real numbers than massage estimated numbers like this. The suspense is killing me!

waterrockets 08-15-08 02:18 PM

It sounds like you had an awesome climb. Good job!

Regarding the power estimate, even with the same exact elapsed time on the same day, my hill repeats can vary by close to 10% in power averages depending on my pacing. It depends on how smooth or varied you were (not how smooth or varied you felt).

You're ripe for some data, just buy a used PowerTap and sell it when the Quarq arrives. You'll lose nothing but shipping.

+1 for different tests on different days. I can pretty safely test 5s power during my warmup for my 1m test though. I have to get those explosions ignited to stay primed for the ridiculous.

Bantam 08-15-08 02:26 PM


Originally Posted by waterrockets (Post 7279825)

You're ripe for some data, just buy a used PowerTap and sell it when the Quarq arrives. You'll lose nothing but shipping.

Unless you want to geift it to me. :love:

jmechy 08-15-08 02:34 PM


Originally Posted by umd (Post 7279698)
I suppose. But I think that the factors involved here are straightforward enough that the results would be that far off even if I had used a real power meter. The software takes windspeed, weight, rolling resistance, aero position, etc. into account. Next time I'll borrow someone's PowerTap if I still don't have my Quarq yet...

If you wanted to pick it up from me, i could probably loan mine. Best would be a tuesday or wednesday, but thursday during the day would be fine as long as I got it back before the torture ride from hell.

umd 08-15-08 02:42 PM


Originally Posted by jmechy (Post 7279953)
If you wanted to pick it up from me, i could probably loan mine. Best would be a tuesday or wednesday, but thursday during the day would be fine as long as I got it back before the torture ride from hell.

I may take you up on that offer.

Ygduf 06-12-10 12:05 AM

just found this now. eye opening.

My numbers, at 77.1kg

5" : 11.1w/kg
1': 6.2w/kg
5': 4.58w/kg
20': 4.2w/kg

so uh, talk about no sprint... I'm like, in the completely untrained range. gurt.

Homebrew01 06-12-10 04:00 AM

Nothing like a 2 year old thread to get the day started.

umd 06-12-10 07:49 AM

wow, blast from the past.

Note that those numbers were estimate from calculated power, but I have since hit those numbers with a real power meter. At least for 20 minutes, not necessarily actual FTP...

mattm 06-12-10 09:39 AM

I thought umd had gone crazy, then I saw the date, lol..

My e-wang chart's "cats" are way shifted tho, has it changed over the years? (using wko)


All times are GMT -6. The time now is 10:31 AM.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.