Author Topic: How much power?  (Read 6875 times)

Re: How much power?
« Reply #50 on: June 05, 2018, 03:21:32 pm »
I also want to test the claim that putting Techwind panniers on your front wheel can reduce drag by 7%  http://cycledifferent.com/angletech-techwind-panniers/

“The rear of the ANGLETECH TECHWIND’S™ are square profile to catch those tailwinds and blow you down the road.”

Is this a joke?  Have they never heard of vortex shedding/flow separation? ??? It's not only the leading surface that matters!

https://www.youtube.com/watch?v=O-FI6A8NRZI

Apostrophe criminals too. Sickening.

Porkins

  • Formerly Nick H. And a long time ago etc, Eurostar
Re: How much power?
« Reply #51 on: June 05, 2018, 05:49:38 pm »
They claim it was proven in a wind tunnel test by the bloke who designed zzipper fairings. I've emailed them asking for more info but they never reply. I did buy the panniers tho, when I was in the US. I like the clean look. They have stiffened sides. If I buy a meter I'll try to do a comparison between crinkly panniers and smooth ones.

Re: How much power?
« Reply #52 on: June 05, 2018, 06:12:53 pm »
I have missed some of the aerodynamics claims having been out of the game for a while. I think that cycling must be one of the few places that looks to employ people who have a mixed speciality with aerodynamics and marketing.

I should add, that none of their specialities are aerodynamics. Or marketing. They probably are really good at rubbing their tummy while patting their head though.

Porkins

  • Formerly Nick H. And a long time ago etc, Eurostar
Re: How much power?
« Reply #53 on: June 06, 2018, 10:04:51 pm »
I think the price of the shortened spindles will probably rule out the IQ2 for me. My Q factor is already 170mm, so there's no leeway...IQ2 would increase it to 202. A pair of IQ2 meters with a pair of Ultegra pedals is planned to cost £575. The Favero Assioma Duo can be had new for under £550 on ebay most weeks. With luck the IQ2's shipment will push down competitors' prices, so maybe I'll wait a year and get some 2nd hand Vector3 or Assioma for £300 or something. I dunno. These pedal prices are really pissing on some chips. I emailed IQ2 about it and they say there's no profit margin:
Quote
Please consider that we buy the original paddle from Shimano.
We fabricate the special titanium short paddle spindel.
After this we manually replace it for you so for you it's a unboxing, install and go riding. 

So the price actually is to low, but at this price point we can support the people that whant it,
but not go out off business because of it.

quixoticgeek

  • Mostly Harmless
Re: How much power?
« Reply #54 on: June 06, 2018, 10:14:05 pm »
I think the price of the shortened spindles will probably rule out the IQ2 for me. My Q factor is already 170mm, so there's no leeway...IQ2 would increase it to 202. A pair of IQ2 meters with a pair of Ultegra pedals is planned to cost £575. The Favero Assioma Duo can be had new for under £550 on ebay most weeks. With luck the IQ2's shipment will push down competitors' prices, so maybe I'll wait a year and get some 2nd hand Vector3 or Assioma for £300 or something. I dunno. These pedal prices are really pissing on some chips. I emailed IQ2 about it and they say there's no profit margin:
Quote
Please consider that we buy the original paddle from Shimano.
We fabricate the special titanium short paddle spindel.
After this we manually replace it for you so for you it's a unboxing, install and go riding. 

So the price actually is to low, but at this price point we can support the people that whant it,
but not go out off business because of it.

That makes sense, paying Dutch labour rates to install the new spindel is not going to be cheap. And they are adding titanium (which is expensive to machine). I can see why they are charging as much as they are. I can also see why some wouldn't want the extra expense.

Fortunately for me, I'm hoping to fit the IQ2 to a FSA crankset with a 146mm Q factor, which means I will only gain 8mm on what I cam currently riding.  I wonder if anyone else will come up with a similar design, but with a smaller Q factor...

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: How much power?
« Reply #55 on: June 07, 2018, 10:18:02 am »
Having ordered the IQ2's, all this talk of Q factors started to worry me so I've just measured the 2 bikes I'll most likely use them on.  The Cervelo is 145 - the Van Nic a bit wider at 155.  I reckon I should be OK with the additional 16mm on both of those as my tourer is a whopping 170 and doesn't seem to be an issue.

Should really have done this before ordering  :facepalm:

Zed43

  • prefers UK hills over Dutch mountains
Re: How much power?
« Reply #56 on: June 07, 2018, 06:02:40 pm »
Maybe you should budget for the Vector 3 if you want to be sure of buying something!
Just don't, they're horrible.

Battery life sucks; Garmins says 120 hours but the most I got out of a set of LR44's (the alkaline kind that everyone sells) is ~ 30 hours, in nice weather at that. Batteries are expensive (£8 a set) and fiddly to install. The left (master) pedal often loses connection with the right one, meaning only half the power is reported. Also lots of power spikes; I mean, really, 37400W????

Get a PowerTap G3 hub, or a Quarq DZero crankset. They just work.

LEE

  • "Shut Up Jens" - Legs.
Re: How much power?
« Reply #57 on: June 07, 2018, 06:18:08 pm »
power on its own means so little, there's torque...low power high torque can be very fast, as can be loads of drugs, low torque

What does "low power high torque" mean?

Power is directly linked to Torque (it's sort of "Torques per Second" .  Same as Joules/sec).

I think you may mean low cadence, high power (but that translates to high torque, high power).

What the top pro riders have though is high cadence AND high torque...that results in superhuman power.  Froome spins quicker but I bet he still generates more torque on his pedal stroke than even the best club riders.
Some people say I'm self-obsessed but that's enough about them.

Re: How much power?
« Reply #58 on: June 07, 2018, 08:52:39 pm »
Maybe you should budget for the Vector 3 if you want to be sure of buying something!
Just don't, they're horrible.

Battery life sucks; Garmins says 120 hours but the most I got out of a set of LR44's (the alkaline kind that everyone sells) is ~ 30 hours, in nice weather at that. Batteries are expensive (£8 a set) and fiddly to install. The left (master) pedal often loses connection with the right one, meaning only half the power is reported. Also lots of power spikes; I mean, really, 37400W????

Get a PowerTap G3 hub, or a Quarq DZero crankset. They just work.

Power2Max cranksets are pretty solid as well.

Re: How much power?
« Reply #59 on: June 08, 2018, 02:16:13 pm »
power on its own means so little, there's torque...low power high torque can be very fast, as can be loads of drugs, low torque

What does "low power high torque" mean?

Power is directly linked to Torque (it's sort of "Torques per Second" .  Same as Joules/sec).

I think you may mean low cadence, high power (but that translates to high torque, high power).

What the top pro riders have though is high cadence AND high torque...that results in superhuman power.  Froome spins quicker but I bet he still generates more torque on his pedal stroke than even the best club riders.

Phillipa York wrote an interesting piece about Froome in that he climbs at a high cadence but TTs at a low cadence.    There must be some sort of science behind it.

Re: How much power?
« Reply #60 on: June 08, 2018, 08:01:09 pm »
I wonder if he uses different crank lengths?

simonp

  • Omnomnomnipotent.
Re: How much power?
« Reply #61 on: June 08, 2018, 08:09:40 pm »
I think it’s about inertia. There is less of a deceleration during the off phase of the pedal stroke on the flat vs on a hill. So you can push a bigger gear more easily on the flat.

mattc

  • n.b. have grown beard since photo taken
    • Didcot Audaxes
Re: How much power?
« Reply #62 on: June 11, 2018, 03:15:02 pm »
My gut response is that on a 45minute race you can stress your muscles more than on a 4-6hour stage.

(i.e. lower cadence is more fatiguing, but gives slightly better power - assuming you train for it!)

I don't think there's much hard science to support this, but it fits with stuff that I vaguely recall reading in recent years - and with my totally reliable Mattometer of course  :smug:
Has never ridden RAAM
---------
No.11  Because of the great host of those who dislike the least appearance of "swank " when they travel the roads and lanes. - From Kuklos' 39 Articles

Cudzoziemiec

  • Solar powered, tea fuelled cycle-wol
Re: How much power?
« Reply #63 on: June 20, 2018, 02:40:21 pm »
My gut response is that on a 45minute race you can stress your muscles more than on a 4-6hour stage.

(i.e. lower cadence is more fatiguing, but gives slightly better power - assuming you train for it!)

I don't think there's much hard science to support this, but it fits with stuff that I vaguely recall reading in recent years - and with my totally reliable Mattometer of course  :smug:
So it's Mattomatically possible (just like England winning the World Cup).
"Pick a flower on Earth and you move the farthest star." Dirac.

CrazyEnglishTriathlete

  • Miles eaten don't satisfy hunger
  • 3x Brimstone ancien 3x Pendle/Tan Hill DNF
    • CET Ride Reports and Blogs
Re: How much power?
« Reply #64 on: June 28, 2018, 01:46:38 pm »
The most I got to was when I was training hard in Wattbike class last year.

I was 55 & 80Kg
My 20 minute average* was 309W which extrapolates to 293W for an hour at FTP.
Since 1 hour FTP is commonly used to determine Power:Weight  I was 3.6W/Kg at FTP.

Cycling never felt easier and I was climbing away from all my Audax buddies very easily.

My aim last year was to achieve 4W/Kg but life got in the way and I let it slide.  I'm not willing to put myself through the pain to get to 4W/Kg now. 

It made me realise that the top Pro cyclists aren't even human, because they are pushing >450Watts for an hour in a 55km time trial. 
If you can't relate to that then I urge you to try a Wattbike/Zwift trainer just once and see how long you can hang on to 450Watts at 90-100rpm.

I agree with this.

I mentioned in another thread that I'm a relatively recent cycling returnee, and I've found the data now available via power measurements and Strava more interesting than I'd expected!

I ride in the Peak District, which has no shortage of cyclists, so there's plenty of steep hills in Strava that thousands upon thousands have ridden including plenty of very talented cyclists. My last FTP test was ~3.2 w/kg, and I'm finding that on the steeper hills this power-to-weight has me doing times that are roughly around the top 20%-ish region.

My current goal is to get to ~3.5 w/kg, which I estimate would be approx where I was a few years back when riding pretty well. I rode a bunch of short hilly audaxes back then and would tend to be in the front group of climbers, only occasionally coming across a fellow audaxer climbing significantly faster, which ties in well with your experience at 3.6 w/kg.

At 4w/kg, I can see how very few audaxers could live with you on hills, considering the audaxing demographic and the long distance focus. I don't think I have the appetite (or maybe ability?) for the gruelling punishment it'd require, but if I somehow did achieve 4w/kg I've promised myself a new bike outfitted with Di2, dual-sided power meter and hydraulic disc brakes, etc, fairly safe in the knowledge I won't be paying out...

One of the fascinating things about the Strava data is the vast gulf it exposes lying between someone like me who's reasonably fit (for my age!) but with no innate talent, and the fast people who post times that are mind blowing. It's not just the handful pro-level names, but a whole swathe of extremely fit and talented cyclists posting times that I can only marvel at. Where did talent + hard work ever get anyone?  ;D

I love like the reality-check this all provides. I've always thought testers were mental - which they clearly are - but maybe I'm beginning to get a glimpse of what's in their heads?

I rode up the Hochwald 3.1km @10% which was a good point at which to test my watts/kg - 311Watts for 17 minutes, 83kg.  My bike (unknown to me at the time had a crack in the frame which could have caused some power leakage, although it wasn't creaking much up the hill).  So that gives 3.75W/kg.  There are some AUK anciens that drop me on hills, but I'm usually somewhere near the front but not at the front on hilly events, especially ones with longer hills, so I reckon that you are right with 4W/kg being a level which only a small proportion of randonneurs exceed. 
Eddington Numbers 125 (imperial), 168 (metric) 518 (furlongs)  111 (nautical miles)

zigzag

  • unfuckwithable
Re: How much power?
« Reply #65 on: June 28, 2018, 02:29:58 pm »
I rode up the Hochwald 3.1km @10% which was a good point at which to test my watts/kg - 311Watts for 17 minutes, 83kg.  My bike (unknown to me at the time had a crack in the frame which could have caused some power leakage, although it wasn't creaking much up the hill).  So that gives 3.75W/kg.  There are some AUK anciens that drop me on hills, but I'm usually somewhere near the front but not at the front on hilly events, especially ones with longer hills, so I reckon that you are right with 4W/kg being a level which only a small proportion of randonneurs exceed.

assuming that:
* the pacing was consistent
* the power was measured accurately
* the same effort could be sustained for another 3min

that gives power-to-weight of 3.37w/kg (311 x 0.9 / 83). i found that it is incredibly hard to raise the ftp after hitting one's "natural plateau" every little gain requires enormous amount of work..

LMT

Re: How much power?
« Reply #66 on: June 28, 2018, 07:57:42 pm »
I rode up the Hochwald 3.1km @10% which was a good point at which to test my watts/kg - 311Watts for 17 minutes, 83kg.  My bike (unknown to me at the time had a crack in the frame which could have caused some power leakage, although it wasn't creaking much up the hill).  So that gives 3.75W/kg.  There are some AUK anciens that drop me on hills, but I'm usually somewhere near the front but not at the front on hilly events, especially ones with longer hills, so I reckon that you are right with 4W/kg being a level which only a small proportion of randonneurs exceed.

assuming that:
* the pacing was consistent
* the power was measured accurately
* the same effort could be sustained for another 3min

that gives power-to-weight of 3.37w/kg (311 x 0.9 / 83). i found that it is incredibly hard to raise the ftp after hitting one's "natural plateau" every little gain requires enormous amount of work..

easier to lose 13kg.

CrazyEnglishTriathlete

  • Miles eaten don't satisfy hunger
  • 3x Brimstone ancien 3x Pendle/Tan Hill DNF
    • CET Ride Reports and Blogs
Re: How much power?
« Reply #67 on: July 03, 2018, 02:24:59 pm »
I rode up the Hochwald 3.1km @10% which was a good point at which to test my watts/kg - 311Watts for 17 minutes, 83kg.  My bike (unknown to me at the time had a crack in the frame which could have caused some power leakage, although it wasn't creaking much up the hill).  So that gives 3.75W/kg.  There are some AUK anciens that drop me on hills, but I'm usually somewhere near the front but not at the front on hilly events, especially ones with longer hills, so I reckon that you are right with 4W/kg being a level which only a small proportion of randonneurs exceed.

assuming that:
* the pacing was consistent
* the power was measured accurately
* the same effort could be sustained for another 3min

that gives power-to-weight of 3.37w/kg (311 x 0.9 / 83). i found that it is incredibly hard to raise the ftp after hitting one's "natural plateau" every little gain requires enormous amount of work..

Looking at the Garmin the speed was consistent.  Time was right to the second as I looked at the timer on the Garmin on bottom and top, both very sharply defined and the height gain was taken from spot heights.  The power is based on a British Cycling calculator using distance, altitude, my weight 83kg + bike weight 10kg.  I wasn't on the point of collapse at the top - the presence of a visible col over the last few hundred meters was clearly a motivating factor - but if it had been a false summit I think I would have kept going at the same cadence for quite a time further.  Wasn't sure where the 0.9 came in the above formula.

Possibly the presence of someone overtaking me on an e-bike provided a motivating factor.  It certainly surprised me as I became aware of a rider passing me half way up  :facepalm:
Eddington Numbers 125 (imperial), 168 (metric) 518 (furlongs)  111 (nautical miles)

LMT

Re: How much power?
« Reply #68 on: July 03, 2018, 10:18:31 pm »
I rode up the Hochwald 3.1km @10% which was a good point at which to test my watts/kg - 311Watts for 17 minutes, 83kg.  My bike (unknown to me at the time had a crack in the frame which could have caused some power leakage, although it wasn't creaking much up the hill).  So that gives 3.75W/kg.  There are some AUK anciens that drop me on hills, but I'm usually somewhere near the front but not at the front on hilly events, especially ones with longer hills, so I reckon that you are right with 4W/kg being a level which only a small proportion of randonneurs exceed.

assuming that:
* the pacing was consistent
* the power was measured accurately
* the same effort could be sustained for another 3min

that gives power-to-weight of 3.37w/kg (311 x 0.9 / 83). i found that it is incredibly hard to raise the ftp after hitting one's "natural plateau" every little gain requires enormous amount of work..

Looking at the Garmin the speed was consistent.  Time was right to the second as I looked at the timer on the Garmin on bottom and top, both very sharply defined and the height gain was taken from spot heights.  The power is based on a British Cycling calculator using distance, altitude, my weight 83kg + bike weight 10kg.  I wasn't on the point of collapse at the top - the presence of a visible col over the last few hundred meters was clearly a motivating factor - but if it had been a false summit I think I would have kept going at the same cadence for quite a time further.  Wasn't sure where the 0.9 came in the above formula.

Possibly the presence of someone overtaking me on an e-bike provided a motivating factor.  It certainly surprised me as I became aware of a rider passing me half way up  :facepalm:

Coefficient of friction innit.

Re: How much power?
« Reply #69 on: December 20, 2018, 04:33:59 pm »
Not about cycling, not really . . .

OK, so a few weeks ago I was using a hand crank exercise machine. With a variable setting ('Rolling hills') I could sustain 180W, and do 30s 'sprints' of 300W. 20 min sessions.

I'm going to a different gym and using a cross trainer (I've been doing a bit of jogging, 5km in about 25-26min). According to the cross-trainer, I'm sustaining 160W, maxing at 240W.

The cross-trainer is killing me.

This doesn't make sense. The cross-trainer is using my legs and arms. My legs are dying. I'm putting out fewer watts, heart rate about 170. I don't have the arms of a beast!
<i>Marmite slave</i>

Kim

  • Timelord
Re: How much power?
« Reply #70 on: December 20, 2018, 04:35:05 pm »
I'll guess that neither device had a calibration certificate...
Careful, Kim. Your sarcasm's showing...

Re: How much power?
« Reply #71 on: December 20, 2018, 04:55:40 pm »
I'll guess that neither device had a calibration certificate...
I did wonder about that. They are fairly wide variations though!
Monday I used one machine at the gym and had a hard workout. Wed used a different one, same settings and was dying. Either I was tired or the machines were serving different workloads on the same settings.
<i>Marmite slave</i>

simonp

  • Omnomnomnipotent.
Re: How much power?
« Reply #72 on: December 20, 2018, 05:13:20 pm »
You’re supporting your weight on your legs on the cross trainer. I’m not convinced it’s a very efficient motion either. Also more muscle is active for the same power => might be your hr is higher. I experience similar on a rowing machine - same watts results in a higher heart rate.