Poll: What's your Functional Threshold power?

ric_stern/RST

i've tested against several of them (each unit gave different, but wildly optimistic readings). I've also tested quite a few other trainers that incorporate a 'power meter', and in general they're wildly optimistic too.

Off the top of my head, i've tested several Computrainers, a few Tacx Basics/Grand Excels, a Fortius (couldn't get it to work with my Power Tap), several Elite Axioms, about five or six Cateye Cyclosimulators, a Cyclops trainer and possibly some others (can't recall off the top of my head).

so what if Elite make more trainers than anyone else? Quantity production doesn't necessarily mean accurate.

Ric

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tonyzackery

Preaching to the choir, my friend. I know you mean well though...

tonyzackery

Ric, as always, your expert analysis and perspective are always spot-on. You may have the last word. You're welcome...

rmur17

Originally Posted by peterwright
the holster 370 67 5.52
Camoscio 340 62 5.48
scotmart 385 72 5.35 19:58 (47:21 on a 37.8km course)
musher 340 64 5.31
bigmatt 396 75 5.28
BullGod 365 70 5.21
joemw 354 68 5.20
whoawhoa 320 62.5 5.12
gvanwagner 325 64 5.08
musher 318 65 4.89
Markster 335 70 4.79 19:57 51:55
gonzalovilaseca 310 68 4.56
kennethn 320 70.3 4.55
JohnMeyers 350 77 4.54
PSUCycling 305 68 4.48 (40k 58:30 @ 250W ave-asthema!)
peterpen 290 65 4.46
zaskar 280 63 4.44
midbunchlurker 275 62 4.43
joule 266 60 4.43
HammerHead 300 68 4.41
bikeguy 315 72 4.38 5 km rolling TT, 7:15; standard, no aero bars, after 90k
rouleur 315 72 4.38
postal_bag 333 76 4.38
Thorman 340 78 4.36
rmur 370 85 4.35 (PT Pro, ~380W on SRM)
Chowderm 325 75 4.33 52:19
Lazy Llama 286 66 4.33 13.3 mi TT, 30:12
dshep27283 345 80 4.31
RobM 312 73 4.27
cadence230 280 4.24
mattv2099 314 75 4.19
Stanette 313 75 4.17
Atsic 252 61 4.13
yzfrr11 310 75 4.13
Xav 318 77 4.13
pledac 285 69 4.13
Spunout 280 68 4.12
NomadVW 322 78 4.12
RapDaddyo 325 80 4.06
jbvcoaching 310 77 4.03 21:10 52:17
velobob 310 77 4.03
jack.hutchinson 285 71 4.01
PeterWright 280 70 4
bspurgeon 315 78.5 3.99
K50 275 69 3.99, (no TT's) all XC baby!
cube 290 73 3.97
Old Junker 250 63 3.97
velomanct 310 79 3.92
My02Sti 305 79 3.86
Otb4evr 385 100 3.85 22:19 58:48
BlueJersey 230 60 3.83
robkit 280 75 3.73
amartinez 250 67 3.73
Trailhead 312 84 3.71
11ring 256 70 3.66 22.10
sugaken 240 66 3.64
woodgab 321 89 3.61
bigbevans 260 73 3.56 21:30 (270 w) 56:46
Hookyrider 284 80 3.55
Krazyderek 260 78 3.33
AndROOb 232 71 3.27
spomanski 310 96 3.23
netscriber 143 47 3.04
beerco 220 78 2.82
fmarques25 204 74 2.76
offthebackCT 200 76 2.63

__________________
rmur

postal_bag

When do you all weigh yourselves, anyway?

POGATA

What scale factor did you use on the Tacx trainers?

BullGod

FWIW forum user "Solar Energy" has confirmed to me (by testing against his powertap) that if you use a Tacx Flow - you need to enter your weight value (if possible) at around 30kg less than you actually weigh - so I weigh 70kg - but I enter my weight as 40kg. You then need to have max tyre pressure and get the screw so tight that you can only just push the lever down to get the roller against the tyre. You should then ignore calibration (which tends to make the machine overestimate power).

When he did this the watt value he saw on the Taxc display screen was around 5% lower than the value on his powertap.

When I set the weight value at 70kg my FTP is about 365w.....when I set it up as per Solar Energy's recommendations it went down to 325w....

it is still not accurate power - but at least you know that it will tend more to be underestimating rather than overestimating. I know which one I'd rather have.

POGATA

Scale factor!

tonyzackery

http://www.pezcyclingnews.com/?pg=fullstory&id=4569

Review of ergometers. Note that the stationary trainers in this review UNDERESTIMATED power. Take it for what it's worth...

It's all relative, not all of it's relevant...

RapDaddyo

It's too bad the author didn't do more testing, such as power drift over the course of a typical L4 interval and seeing if a PT works on the trainer (e.g., compatibility problems between certain Tacx trainers and PTs). He talks about a 10% difference as "acceptable." I don't agree. A difference of 10% is huge.

NomadVW

I can't wait until summer is fully here and we can stop talking about trainers!

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Cycling in Iwakuni Blog

bikeguy

Originally Posted by peterwright
the holster 370 67 5.52
Camoscio 340 62 5.48
scotmart 385 72 5.35 19:58 (47:21 on a 37.8km course)
musher 340 64 5.31
bigmatt 396 75 5.28
BullGod 365 70 5.21
joemw 354 68 5.20
whoawhoa 320 62.5 5.12
gvanwagner 325 64 5.08
musher 318 65 4.89
Markster 335 70 4.79 19:57 51:55
2007 bikeguy 340 72 kg 4.71 W/kg, 12 minute power 400 (+?) w @ 100 rpm
postal_bag 345 75 4.6
gonzalovilaseca 310 68 4.56
kennethn 320 70.3 4.55
JohnMeyers 350 77 4.54
PSUCycling 305 68 4.48 (40k 58:30 @ 250W ave-asthema!)
peterpen 290 65 4.46
zaskar 280 63 4.44
midbunchlurker 275 62 4.43
joule 266 60 4.43
HammerHead 300 68 4.41
k
rouleur 315 72 4.38
Thorman 340 78 4.36
rmur 370 85 4.35 (PT Pro, ~380W on SRM)
Chowderm 325 75 4.33 52:19
Lazy Llama 286 66 4.33 13.3 mi TT, 30:12
dshep27283 345 80 4.31
RobM 312 73 4.27
2006 bikeguy 315 74 4.26 corrected for weight
cadence230 280 4.24
mattv2099 314 75 4.19
Stanette 313 75 4.17
Atsic 252 61 4.13
yzfrr11 310 75 4.13
Xav 318 77 4.13
pledac 285 69 4.13
Spunout 280 68 4.12
NomadVW 322 78 4.12
RapDaddyo 325 80 4.06
jbvcoaching 310 77 4.03 21:10 52:17
velobob 310 77 4.03
jack.hutchinson 285 71 4.01
PeterWright 280 70 4
bspurgeon 315 78.5 3.99
K50 275 69 3.99, (no TT's) all XC baby!
cube 290 73 3.97
Old Junker 250 63 3.97
velomanct 310 79 3.92
My02Sti 305 79 3.86
Otb4evr 385 100 3.85 22:19 58:48
BlueJersey 230 60 3.83
robkit 280 75 3.73
amartinez 250 67 3.73
Trailhead 312 84 3.71
11ring 256 70 3.66 22.10
sugaken 240 66 3.64
woodgab 321 89 3.61
bigbevans 260 73 3.56 21:30 (270 w) 56:46
Hookyrider 284 80 3.55
Krazyderek 260 78 3.33
AndROOb 232 71 3.27
spomanski 310 96 3.23
netscriber 143 47 3.04
beerco 220 78 2.82
fmarques25 204 74 2.76
offthebackCT 200 76 2.63

Just destroyed my PB today for 12 continuous minute power, I'm starting to take a hand off the handlebars riding up short hills and it feels comfortable.
I have a significant fall off in power when riding on aerobars and somewhat wide shoulders, so my TT probably won't be great ever, but I will clean up going up hills. These power tests are done on a bike that's a bit more upright than when in the drops on my road bike.

-bikeguy

NomadVW

Week of testing done... back in the training load deficit!

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Cycling in Iwakuni Blog

gggossel

FTP=266
Age: 29
Wt= 74.5Kg

Up 15W from a month ago.