"The 33"-Road Bike Racing - Crits and power records

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View Full Version : Crits and power records


king-tony
03-11-08, 07:47 PM
I raced my first crit with a power meter this weekend and am not sure what to do with the data. This was a 1km course with six turns and a hill. It was very technical and showed me how much I have to learn about crit racing and bike handling. My normalized power for the 25 min crit was 439 watts with an average of 415. This destroyed pretty much every power record I have except for 30s and 1min. What should I do with this data? Should I just delete it from WKO+? I did learn some things from the data - primarily that I wasted a lot of effort by not being smooth in the first half of the race. The second half of the race had an average normalized power of 52watts less than the first half with a faster speed and the second half contained my attack lap as well. What does everyone else do with the crit data from their power meter?

Thanks


fastfly
03-11-08, 07:57 PM
Isn't 439watts for 25min pretty good?

ElJamoquio
03-11-08, 08:00 PM
Uh, way more than *pretty* good.


garysol1
03-11-08, 08:01 PM
. My normalized power for the 25 min crit was 439 watts with an average of 415.

That sounds god awfully high or very painful.....

fastfly
03-11-08, 08:01 PM
That's what I meant.

garysol1
03-11-08, 08:06 PM
What type of Meter are you using Tony?


EDIT....Powertap. I found your thread from the TT where you said:


"I check my PT to see how bad my performance was and then I started to realize how sucky my ride was. 1:06:46 for 40.1k, avg power of only 279 with normalized @ 292. Avg HR was 155 (LTHR for me is 156). Outbound power looked a little better at 290 avg and 302 normalized, but was still way off my FTP and what I thought I could do. I guess the gearing issue hurt me some, but I left feeling like I may have left some time out there."



302 normalized for a TT then getting 439 for a crit just does not sound right. I am not sure what I would do. Even if your hub was not zero'd out I don't think it would cause that big of a difference.

king-tony
03-11-08, 08:12 PM
Isn't 439watts for 25min pretty good?

That is the point. When you are looking at your records you are generally wanting the power over the time period to be flat. The nature of a crit (at least this type of course is that there is a lot of on/off). So if you are sprinting up a short hill and avg 600 watts for 30 seconds and then do 200 watts down the back side it gives you an average of 400 for the time period. Power curves (at least as I use them) help me to know how long I can hold a certain wattage. So if I want to attack or try to bridge or even a short TT I know how long I can hold a wattage. This crit data is not reflective of my power (my real power is much lower than this for everything from 2-20 minutes). Here is what the file looks like unless the PT is malfunctioning from the previous day's icy time trial I assume it is accurate.

http://i233.photobucket.com/albums/ee312/king-tony/mryvllecrit.jpg

timmyquest
03-11-08, 08:15 PM
So if you are sprinting up a short hill and avg 600 watts for 30 seconds and then do 200 watts down the back side it gives you an average of 400 for the time period.

Assuming you go as fast up as you do down...

garysol1
03-11-08, 08:17 PM
Minimum power was 67watts........
I am thinking you need to calibrate BIG TIME Tony.
I think....again think....that all your numbers will be 67 watts to high

king-tony
03-11-08, 08:23 PM
Minimum power was 67watts........
I am thinking you need to calibrate BIG TIME Tony

I am thinking you are right. I stuck it on the bike right now and spun it up. It did drop back to zero, but probably 4-5 seconds after I quit spinning the pedals.

garysol1
03-11-08, 08:25 PM
I am thinking you are right. I stuck it on the bike right now and spun it up. It did drop back to zero, but probably 4-5 seconds after I quit spinning the pedals.


That is ok...It takes a few seconds. But from the looks of your record it never went to zero even before you started.

king-tony
03-11-08, 08:32 PM
That is ok...It takes a few seconds. But from the looks of your record it never went to zero even before you started.

My cadence never dropped below 40 either. I cleared it just before the start so my warm-up data is not on there. Would the sampling time cause this? I zeroed the hub just now and it is seems to be doing exactly as it was before. When I look at my cool-down data it does not show the power dropping below 13 or the cadence below 31. Hope my hub is not fried...or I guess frozen may be more accurate.

garysol1
03-11-08, 08:36 PM
My cadence never dropped below 40 either. I cleared it just before the start so my warm-up data is not on there. Would the sampling time cause this? .

Max sampling is what.....4 seconds? I wouldn't think so. Maybe it was a fluke or maybe there were some high tension wires near by. Hop on the trainer and do 30 minutes with intermittent power and coasting and see what it looks like. Wish I could be of more help.

king-tony
03-11-08, 08:49 PM
Max sampling is what.....4 seconds? I wouldn't think so. Maybe it was a fluke or maybe there were some high tension wires near by. Hop on the trainer and do 30 minutes with intermittent power and coasting and see what it looks like. Wish I could be of more help.

You were a big help actually. If you had not said anything I would most likely have continued to use bad data. I'll call Saris and see what they have to say.

wfrogge
03-11-08, 08:50 PM
I would forward your WKO data to Slipstream but thats me.

king-tony
03-11-08, 09:00 PM
I would forward your WKO data to Slipstream but thats me.

I look terrible in argyle. I think I'll send it to Mr. Ball.

cslone
03-11-08, 09:25 PM
Look at some of the FAQ's on Saris site for troubleshooting and zeroing torque. Or look up the stomp test on the google wattage forums to check the calibration. One would guess that at some point during the race you stopped pedaling, if only for a few seconds, which is why the non-zero crank and hub torque would indicate that something was wrong with the hub. It may just be a torque reset. I do mine once a week just to be safe.

I would think 440w average would net you a win in the 4's too. :D

brianappleby
03-11-08, 09:41 PM
zero the torque. My PT always runs high when it's cold outside. Zero the torque and everything will be fine. You can even do this while you're riding as long as you have some time to coast.

Interestingly enough, the PT can zero itself if it's reading too low. It knows that there can't be a negative torque, so it can zero itself in that case.

If it's reading high though, there's no way for the PT to know.

Look at your torque while you're coasting. If it isn't zero, that's proof of your issue.

Looking at your power while coasting isn't the same thing, and it won't be helpful.

KendallF
03-11-08, 10:07 PM
Yes, zero your torque. With the chain slack, press the left button until you're on the Watts line, press and hold the right button until the "watts" starts to blink. This will be torque mode, and the displayed number should be zero. I'm guessing it won't be. :) If it displays 35, for example, that's the amount of torque it added to every reading. You can actually write down this number and use a spreadsheet to subtract this amount from your torque readings to correct your power, if you're really concerned with saving the race data.

Anyway, now press and hold the right button again until it reads zero. Release and press the right button briefly to make the "watts" stop blinking and go back to power display. You've just zeroed the torque; you can do this coasting as well as long as the chain's slack.

DrWJODonnell
03-11-08, 10:30 PM
How much do you weigh? While it seems that either your threshold power is off, or your zeroing was wrong, just looking at the graph and shifting it down 70 watts would still be an amazing effort, though if you are a big guy, maybe not so much. Nice job with both races.

ElJamoquio
03-12-08, 03:36 AM
Assuming non-zero torque, you can still get good data out of it if you weren't spinning at *some* point - say, even at the end of the race.

Port it to excel, subtract the offset torque from the recorded torque, and re-calculate the power.

king-tony
03-12-08, 05:34 AM
How much do you weigh? While it seems that either your threshold power is off, or your zeroing was wrong, just looking at the graph and shifting it down 70 watts would still be an amazing effort, though if you are a big guy, maybe not so much. Nice job with both races.

I weigh 195#.

king-tony
03-12-08, 05:36 AM
Thanks for all the help guys. I've got a 4 minute climb near my house that I have a lot of data on. I'll ride that after re-zeroing the PT and see what it says. I hope it was just the cold weather and that I won't have to send it back.

kensuf
03-12-08, 05:51 AM
I raced my first crit with a power meter this weekend and am not sure what to do with the data. This was a 1km course with six turns and a hill. It was very technical and showed me how much I have to learn about crit racing and bike handling. My normalized power for the 25 min crit was 439 watts with an average of 415. This destroyed pretty much every power record I have except for 30s and 1min. What should I do with this data? Should I just delete it from WKO+? I did learn some things from the data - primarily that I wasted a lot of effort by not being smooth in the first half of the race. The second half of the race had an average normalized power of 52watts less than the first half with a faster speed and the second half contained my attack lap as well. What does everyone else do with the crit data from their power meter?

Thanks

Make graphs and post them on bf.net??

And all though it's just HR data, I'll oblige.

http://www.astro.ufl.edu/~ken/hrm/lake-mary-crit_2008.JPG

kukusz
03-12-08, 07:24 AM
http://www.midweekclub.ca/powerFAQ.htm#Q46

waterrockets
03-12-08, 07:27 AM
Kensuf: Ouch.

king-tony
03-12-08, 07:53 AM
http://www.midweekclub.ca/powerFAQ.htm#Q46

I think I'll just delete the file.....

kensuf
03-12-08, 07:54 AM
Kensuf: Ouch.

Meh, the first half was pretty easy as I just sat in and tried to get a sing-a-long going from mid-pack. About 23 minutes into the race I broke away and tried to go for the W, that's when the HR went up a little.. Unfortunately, I got wrapped up like a burrito with two laps to go and decided to just sit up on the last lap when the squirrels came out for the sprint. :(

But hey, I won a prime.

king-tony
03-12-08, 07:56 AM
Meh, the first half was pretty easy as I just sat in and tried to get a sing-a-long going from mid-pack. About 23 minutes into the race I broke away and tried to go for the W, that's when the HR went up a little.. Unfortunately, I got wrapped up like a burrito with two laps to go and decided to just sit up on the last lap when the squirrels came out for the sprint. :(

But hey, I won a prime.

Your avg. HR is 12 bpm higher than my max. Unreal.

kensuf
03-12-08, 07:57 AM
Your avg. HR is 12 bpm higher than my max. Unreal.

Well, I am 39 you know.. ;)

transplant
03-12-08, 08:10 AM
Ken, the BF hivemind requires your last name

garysol1
03-12-08, 08:27 AM
Ken, the BF hivemind requires your last name

Suf :)

ElJamoquio
03-12-08, 08:54 AM
I weigh 195#.

Hallelujah. I was just going to walk up to the top of the building, what with your still-fantastic HR and power numbers.

kensuf
03-12-08, 09:05 AM
Suf :)

Actually, it's Paquefodher.

king-tony
03-12-08, 11:53 AM
Hallelujah. I was just going to walk up to the top of the building, what with your still-fantastic HR and power numbers.

My HR numbers suck. I have very small ranges because my max is so low.

garysol1
03-12-08, 01:57 PM
Actually, it's Paquefodher.

Suf is much easier.....Can we just use that?

kensuf
03-12-08, 02:23 PM
Suf is much easier.....Can we just use that?

Works for me.

bdcheung
03-12-08, 02:39 PM
I wonder if he missed the "packfodder" joke...

ElJamoquio
03-12-08, 02:52 PM
I know I did.

garysol1
03-12-08, 03:31 PM
I missed it...now I get it.....:o