POWER

[Rob3rt]

Typically 25-30min & 75-80min but mostly I do hill climb style TTs. Best 16km has been 18m 27s as art of a 46m 52s 40km... continuing on to 50.92km over the hour. Those are bent timings though, so hard to quantify against a TT bike.

You put out a lot more power than me (and have a better power/weight ratio, across the board) and my 10TT times are around 24 mins and 25TT times couple of minutes over the hour (hopefully go under the hour soon, especially when the wind dies down enough to ride aero wheels).

What

What kind of power GrasB?

@gam001

1s = 1.73-1.91 (1289w-1424w) - depends on where you chop the pedal strokes.
5s = 1.70hp (1264w)
10s = 1.37hp (1019w)
30s = 1.17hp (873w)
1m = 0.89hp (662w)
5min = 0.60hp (448w)
15min = 0.55hp (409w)
60m = 0.5hp (371w)

and mine

Duration - Power (W)
1s = 981W
10s = 840W
30s = 605W
1 min = 500W
5 min = 390W
20 min = 325W
60 min = 308W

I am a weak sprinter!

 

[GrasB]

You put out a lot more power than me (and have a better power/weight ratio, across the board) and my 10TT times are around 24 mins and 25TT times couple of minutes over the hour (hopefully go under the hour soon, especially when the wind dies down enough to ride aero wheels).

I've also done a lot of things to make me very slippery on the bike. CdA 0.207. In off the shelf & fitted properly trim I was at 0.230. At 30mph that's 35w, or 1.25mph, advantage from about 15 hours of testing.

 

[Rob3rt]

I have an ok position, relatively flat back and good helmet to back transition, fairly open hip angle but could make improvements. I could get a bit lower at the front and possibly stretch myself out a little by pushing the saddle back. I have an Adamo saddle on loan to test, my current saddle wont let me rotate my pelvis forward any more, but the Adamo may help with this. If it does, I should be able to get a very nice position with only a few small adjustments.

I have a FFWD Trispoke wheel ready to go, but been so windy I haven't used it yet, no idea what I can expect to save from it tbh, but it looks great! Will also buy a speedsuit as soon as money allows.

 

[GrasB]

Also the small stuff is important. Using a J bar rather than a flat bar gave me improvements as I can now ride with my fingers overlapping making a clean 'flat' surface for the air to flow over. Also not using an attached valve extension but one of these when needed & tape over the valve hole with as trip of insulation tape also made a measurable difference at 30mph.

 

[Rob3rt]

Also the small stuff is important. Using a J bar rather than a flat bar gave me improvements as I can now ride with my fingers overlapping making a clean 'flat' surface for the air to flow over.

Also going to change to Ski bend extensions, not for aero reasons though, for comfort as the S bend hurt my wrists.

 

[GrasB]

Also going to change to Ski bend extensions, not for aero reasons though, for comfort as the S bend hurt my wrists.

I'm gifted with great flexibility which helps as a lot of stuff 'fits' for me where other people it wouldn't. Unfortunately genetics can't be trained, sure you can maximise what you've got but inherently I can simply bend further than most people.

 

[gam001]

I'm gifted with great flexibility which helps as a lot of stuff 'fits' for me where other people it wouldn't. Unfortunately genetics can't be trained, sure you can maximise what you've got but inherently I can simply bend further than most people.

GrasB - you're so modest

 

[VamP]

My 2p worth.

I'd never recommend anyone buy a used PowerTap. Once they're out of warranty you're looking at around £425 to replace the torque tube. It's impossible to know just how long a torque tube will last, but anything beyond a few years seems to be quite unusual and a couple of years quite normal, especially with the SL+ hub which is poorly sealed and leaks water. My PowerTap Pro+ was trouble free for 2.5 years and then it just died. I decided not to pay the ridiculous £425 for repair and bought a Power2max instead (for about £750).

I wonder if that's Paligap thing, as Saris appear to do very competive repairs, or discounts on new against unsupported models.

I think this discussion is pretty typical of the Saris PT experience.

In fact, I believe that people in the states have been buying the older wired taps to get in on the discounts from Saris.

 

[Rob3rt]

This thread died fast. Question, how often are you guys testing FTP? Do you continue to test during the racing season or do you lift data from races?

(Not so much looking for advice, just resurrecting the thread )

If that isn't interesting enough to keep the thread afloat for a day or so, someone write me a good guide of using Aerolab, hah I have fumbled about using some out and back 10TT data, no specific testing protocols etc and the results are dubious at best (more likely they are utterly wrong, no way am I more slippery wearing winter kit and riding road wheels than full aero wheel setup and a skinsuit, skinsuit is not a proper speedsuit and has pockets on the back, a speedsuit is on the to buy list, once I ascertain a solid opinion on the best one for £200 or less), it would be good to learn how to use it properly, as I plan to make some positional changes after the weekend and will probably ride the club 10 on Monday with the new position!

 

[VamP]

This thread died fast. Question, how often are you guys testing FTP? Do you continue to test during the racing season or do you lift data from races?

(Not so much looking for advice, just resurrecting the thread )

If that isn't interesting enough to keep the thread afloat for a day or so, someone write me a good guide of using Aerolab, hah I have fumbled about using some out and back 10TT data, no specific testing protocols etc and the results are dubious at best (more likely they are utterly wrong, no way am I more slippery wearing winter kit and riding road wheels than full aero wheel setup and a skinsuit, skinsuit is not a proper speedsuit and has pockets on the back, a speedsuit is on the to buy list, once I ascertain a solid opinion on the best one for £200 or less), it would be good to learn how to use it properly, as I plan to make some positional changes after the weekend and will probably ride the club 10 on Monday with the new position!

I'll play.

Aerolab - I swing between thinking it's genius, and not having a clue as to how to use it. Right now, I am in the no clue stage

I tested FTP this week up 15 watts and about half way to what I'd like to see in August. I have seen some sharp increases in 3 - 10 minute power recently as well which is handy. Still useless at sprinting.

Generally speaking I will test when I think that it looks from other data that FTP has gone up. It's a good workoout in its own right so I don't see any reason not to.


Here's another question - do you guys stomp test, and if so, how often?

 

[GrasB]

If that isn't interesting enough to keep the thread afloat for a day or so, someone write me a good guide of using Aerolab, hah I have fumbled about using some out and back 10TT data, no specific testing protocols etc and the results are dubious at best (more likely they are utterly wrong, no way am I more slippery wearing winter kit and riding road wheels than full aero wheel setup and a skinsuit, skinsuit is not a proper speedsuit and has pockets on the back, a speedsuit is on the to buy list, once I ascertain a solid opinion on the best one for £200 or less), it would be good to learn how to use it properly, as I plan to make some positional changes after the weekend and will probably ride the club 10 on Monday with the new position!

Make sure you're getting data points every second or shorter
Make sure you are NOT using GPS data for speed info
Calibrate your cycle comp correctly.
Once that's done you need to pick a good testing venue. That means not much traffic, easy turns & close to your home. You want it to be long enough that you get a good run but short enough that you can do multiple repeated runs (repetition is good). It's great if it's wind sheltered too but that's a nice to have thing that increases the number of testing days you have. From there do several runs at various speeds, clearly mark your runs with speed marker (say a jab of the brakes to take you down to a much lower speed for a second or two. Then you can use aerolab to get to your Crr & CdA info. You can then use the VE method to confirm the number. You often find that multiple CdA/Crr values can give an accurate fit, using VE you can see the tell tails of this in sagging or cresting in the VE plot with the start & end points the same.

 

[Rob3rt]

I'll play.

Aerolab - I swing between thinking it's genius, and not having a clue as to how to use it. Right now, I am in the no clue stage

I tested FTP this week up 15 watts and about half way to what I'd like to see in August. I have seen some sharp increases in 3 - 10 minute power recently as well which is handy. Still useless at sprinting.

Generally speaking I will test when I think that it looks from other data that FTP has gone up. It's a good workoout in its own right so I don't see any reason not to.


Here's another question - do you guys stomp test, and if so, how often?

Same with aerolab, I understand you bang in Crr, if you don't test for it, you can look it up based on your tyres (I think), Rho you calculate based on weather data for the day and time, drivetrain efficiency, you guess at it, 0.96 to 0.98 Offset to match the start point elevations, or click auto and it does it for you, total mass = you and bike and kit. Then it is good to go and you fiddle the CdA slider around to fit the virtual and real elevation data, but what I seem to fall over on, is which features to concentrate on fitting. As none of my data is premeditated test data, just TT data etc that I tried playing with to get the hang of the software, none of mine fit that well so I either match 1 or 2 "features" or the end point. Not a clue what to do here!

No idea what a stomp test is? So no I don;t do it.

 

[GrasB]

Same I understand you bang in Crr, if you don;t test for it, you can look it up based on your tyres (I think), Rho you calculate based on weather data for the day and time, drivetrain efficiency, you guess at it, 0.96 to 0.98 Offset to match the start point elevation, total mass = you and bike and kit. Then it is good to go and you fiddle the CdA slider around to it the virtual and real elevation data, but what I seem to fall over on, is which features to concentrate on fitting. As none of my data is premeditated test data, just TT data etc, then none of mine fit that well so I either match 1 or 2 "features" or the end point. Not a clue what to do here!

No idea what a stomp test is? So no I don;t do it.

Crr has to be 'solved' per venue as does CdA! You can't just guess a Crr & go with it like that.

 

[Rob3rt]

Make sure you're getting data points every second or shorter
Make sure you are NOT using GPS data for speed info
Calibrate your cycle comp correctly.
Once that's done you need to pick a good testing venue. That means not much traffic, easy turns & close to your home. You want it to be long enough that you get a good run but short enough that you can do multiple repeated runs (repetition is good). It's great if it's wind sheltered too but that's a nice to have thing that increases the number of testing days you have. From there do several runs at various speeds, clearly mark your runs with speed marker (say a jab of the brakes to take you down to a much lower speed for a second or two. Then you can use aerolab to get to your Crr & CdA info. You can then use the VE method to confirm the number. You often find that multiple CdA/Crr values can give an accurate fit, using VE you can see the tell tails of this in sagging or cresting in the VE plot with the start & end points the same.

1 sec recording.
GSC-10 sensor for speed.
It is calibrated.

I think getting a good test venue and a relevant value for Crr is the next challenge. Living city centre, test venues don't come easy!

 

[VamP]

Same with aerolab, I understand you bang in Crr, if you don't test for it, you can look it up based on your tyres (I think), Rho you calculate based on weather data for the day and time, drivetrain efficiency, you guess at it, 0.96 to 0.98 Offset to match the start point elevations, or click auto and it does it for you, total mass = you and bike and kit. Then it is good to go and you fiddle the CdA slider around to fit the virtual and real elevation data, but what I seem to fall over on, is which features to concentrate on fitting. As none of my data is premeditated test data, just TT data etc that I tried playing with to get the hang of the software, none of mine fit that well so I either match 1 or 2 "features" or the end point. Not a clue what to do here!

No idea what a stomp test is? So no I don;t do it.

Apparently it only works on wind free days. So there's that to contend with as well

Stomp test is a calibration test on your PM using a known weight (e.g. 10 kg, suspended from your crankset)