Author Topic: How much power?  (Read 6886 times)

Karla

  • car(e) free
    • Lost Byway - around the world by bike
Re: How much power?
« Reply #25 on: May 30, 2018, 09:31:45 am »
power on its own means so little, there's torque...low power high torque can be very fast

Nope

Cudzoziemiec

  • Solar powered, tea fuelled cycle-wol
Re: How much power?
« Reply #26 on: May 30, 2018, 10:10:11 am »
That video rofl lmao! Goggles!
"Pick a flower on Earth and you move the farthest star." Dirac.

Re: How much power?
« Reply #27 on: May 30, 2018, 10:16:40 am »
power on its own means so little, there's torque...low power high torque can be very fast

That's not true.  For maintaining speed, power is the only thing that matters.

https://www.youtube.com/watch?v=u-MH4sf5xkY

funny that many experienced long term folk with power meters actually go on feel for the their fastest performances, and I certainly noticed that I was faster for not looking at mine, having said that they are a good tool if armed with some knowledge of both Coggan and your own body.

I do agree with this, though.  I've been using a crank-based power meter for about 4 years and these days, like you said, my strongest performances are done on feel (both short efforts and audax-length rides).  I try to ignore the power readout while riding, as it just spooks/demoralises me.

It takes some time after getting a power meter to learn how the numbers correspond to the "feel" of a ride.  For example, I now know I can do X watts for Y minutes, and what that effort feels like (both at the start and at the end of the effort), but it took me a good 6 months to learn this.  Until you get to that point, you really have to just observe the power numbers and learn what your body is capable of.

Even then, however, you have to be very careful pacing yourself by power.  Even if you know that you can do X watts for Y minutes on a good day, it's very dangerous to hold yourself to that right from the start.  If it turns out that you're having a bad day, and you ignore the feeling in your legs, you'll blow up early and then you're in real trouble.

On the flip side, though, power meters can be useful for telling you when you're going too hard.  I've lost count of the number of times that I've set off at the start of an audax, with everyone else storming off down the road, while I can see from my power readout that if I push any harder I'll pay for it later in the day.  Invariably I pass them several hours later when they've run out of beans :)  In fact, this happens on pretty much every single audax I've done – you'd think people would know their bodies better!

Personally, I've removed the power readout from my Wahoo ELEMNT, but I do find it useful to have it display my power zones on its LED display (with the zones customised to be more appropriate for long-distance, low-power riding).  This way I get to see roughly what power I'm doing, which is helpful in preventing me from going too hard, without being a distraction.

Re: How much power?
« Reply #28 on: May 30, 2018, 11:04:44 am »
Even then, however, you have to be very careful pacing yourself by power.  Even if you know that you can do X watts for Y minutes on a good day, it's very dangerous to hold yourself to that right from the start.  If it turns out that you're having a bad day, and you ignore the feeling in your legs, you'll blow up early and then you're in real trouble.

On the flip side, though, power meters can be useful for telling you when you're going too hard.  I've lost count of the number of times that I've set off at the start of an audax, with everyone else storming off down the road, while I can see from my power readout that if I push any harder I'll pay for it later in the day.  Invariably I pass them several hours later when they've run out of beans :)  In fact, this happens on pretty much every single audax I've done – you'd think people would know their bodies better!
It depends on what event you are doing. I did too much on "feel" on the last TT I did and reached the end thinking that I could have done another mile or 2 at that speed. My time was down and so were my power numbers - I should have looked at my power meter more! Ultimately, if you blow up on a 10, then you learnt something for next time! ;)

The too hard thing applies to pretty much any sort of ride though. :)

Re: How much power?
« Reply #29 on: May 30, 2018, 11:21:21 am »
Even then, however, you have to be very careful pacing yourself by power.  Even if you know that you can do X watts for Y minutes on a good day, it's very dangerous to hold yourself to that right from the start.  If it turns out that you're having a bad day, and you ignore the feeling in your legs, you'll blow up early and then you're in real trouble.

On the flip side, though, power meters can be useful for telling you when you're going too hard.  I've lost count of the number of times that I've set off at the start of an audax, with everyone else storming off down the road, while I can see from my power readout that if I push any harder I'll pay for it later in the day.  Invariably I pass them several hours later when they've run out of beans :)  In fact, this happens on pretty much every single audax I've done – you'd think people would know their bodies better!
It depends on what event you are doing. I did too much on "feel" on the last TT I did and reached the end thinking that I could have done another mile or 2 at that speed. My time was down and so were my power numbers - I should have looked at my power meter more! Ultimately, if you blow up on a 10, then you learnt something for next time! ;)

The too hard thing applies to pretty much any sort of ride though. :)

True – on a TT you might as well go flat out and hope for the best.  But for audaxes and other long rides that's a very dangerous strategy!

Re: How much power?
« Reply #30 on: May 30, 2018, 08:52:01 pm »
You could look at the Zimanox power meter.  They offer a subscription type service.  I have one on my TT bike and really like it.  Bluetooth and ANT.  Left side only so it would work with any set of chain rings.

I find myself riding to power and HR in slightly different scenarios.  On a long flattish section i will run on HR keeping myHR at top Zone 2.  This means that irrespective of wind, drafting, etc I am doing what i can do solidly for 24+ hours.  Then on hills I will change to power as I know the power levels I can sustain for varying periods and I am willing to "burn matches" on a hill.  (Obviously this does not apply in Wales!)

Porkins

  • Formerly Nick H. And a long time ago etc, Eurostar
Re: How much power?
« Reply #31 on: May 30, 2018, 08:53:02 pm »
I think they will work
I hope you're right, the IQ2 seems the obvious choice for so many reasons. For me, the Dutch team inspire confidence. I like to think they know exactly what they're doing and don't share the American trait of taking a huge punt, then crashing and burning, 

quixoticgeek

  • Mostly Harmless
Re: How much power?
« Reply #32 on: May 30, 2018, 08:56:20 pm »
I hope you're right, seems the obvious choice for so many reasons. For me, the Dutch team inspire confidence. I like to think they know exactly what they're doing and don't share the American trait of taking a huge punt, then crashing and burning,

Aye.

Just notice that I cycle past their office on one of my semi regular routes.

At €350, it's a lot easier to take a punt on than some of the more expensive crank based ones. And of course I can use any pedals. I really like the idea. I just hope they pull it off.

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

jiberjaber

  • ... Fancy Pants \o/ ...
  • ACME S&M^2
Re: How much power?
« Reply #33 on: May 31, 2018, 02:20:35 pm »
Are you waiting til autumn to get customer feedback on the IQ2? How much is known about it? The estimated delivery date is November. Hmmm. Maybe you should budget for the Vector 3 if you want to be sure of buying something!

I do t have the cash for it now, and I am happy to see it proven first.

Vector 3? As in the Garmin pedals? Nah. I don't ride road clip less. So it won't work for me.  Crank power meters aren't an option as I have yet to find one that works with a sub compact 46/30 chainset. Hence liking the iq2.

I think they will work, I'd back the crowd funder if I had the spare cash now.

J

I've moved from Vector2 double sided to 4Viii single sided on 46/30 chainset.  Using Absolute Black chainrings on Ultegra crank arms and now with SPD pedals rather than being limited to only using Keo style with the Garmin set up.  The balance and other Vector metrics were nice to have but overall for monitoring TSS, IF etc the 4Viiii is perfectly adequate and more flexible.  I would have gone down this route initially if it hadn't have been limited by the rear brake design of my original bike preventing anything crank mounted from being used when I started using power meters.

The IQ2 looks interesting as it does open up the potential to be independent of the crank manufacturer which is a good thing - but if q-factor is important to you, then that 16mm is quite a lot, plus the inherent risks outlined in the DCR preview and potential slipping dates.

I guess it depends on when/how long you want to start with power meter based training... you can do a fair bit of HR alone except perhaps but proper HIIT - so you could use a watt bike to get a rough correlation of HR zones / power zones to work from in the intermediate.
Regards,

Joergen

Porkins

  • Formerly Nick H. And a long time ago etc, Eurostar
Re: How much power?
« Reply #34 on: May 31, 2018, 02:24:51 pm »
I read something by the IQ2 people to say they'd be offering shorter pedal spindles to normalise one's Q factor.

quixoticgeek

  • Mostly Harmless
Re: How much power?
« Reply #35 on: May 31, 2018, 09:41:28 pm »
I've moved from Vector2 double sided to 4Viii single sided on 46/30 chainset.  Using Absolute Black chainrings on Ultegra crank arms and now with SPD pedals rather than being limited to only using Keo style with the Garmin set up.  The balance and other Vector metrics were nice to have but overall for monitoring TSS, IF etc the 4Viiii is perfectly adequate and more flexible.  I would have gone down this route initially if it hadn't have been limited by the rear brake design of my original bike preventing anything crank mounted from being used when I started using power meters.

I actually contacted absolute black to see if any of the crank based power meters that are dual sided (4iiii, Stages LR (Ultegra). They did tell me that there is expected to be a new version of their rings 46/30 rings that will fit a DA9100-PM. Which is nice, but the reviews of said power meter are... not good.

Quote
The IQ2 looks interesting as it does open up the potential to be independent of the crank manufacturer which is a good thing - but if q-factor is important to you, then that 16mm is quite a lot, plus the inherent risks outlined in the DCR preview and potential slipping dates.

The 16mm addition to the Q factor is an interesting one. I'm currently riding Deore XT crankset on my bike, that has a Q factor of about 170mm. The FSA SL-K Modula crankset has a Q factor of 146mm. Add on 32mm, and you're actually looking at 178mm. So over what I'm used to now, it would be only 8mm difference...

Q factor seems to largely misunderstood by many people, and I'm not sure just how much research has been done on it's impact.

Quote

I guess it depends on when/how long you want to start with power meter based training... you can do a fair bit of HR alone except perhaps but proper HIIT - so you could use a watt bike to get a rough correlation of HR zones / power zones to work from in the intermediate.

Aye, I need to have a think about how to train effectively. For now I'm concentrating on getting comfortable on the bike. This means I'm on my 3rd saddle in a month... Once I'm comfy, and I can ride all day without having to treat the saddle sores, then I can work on everything else, including shifting the 27kg of body weight. Which should improve my power to weight...

I read something by the IQ2 people to say they'd be offering shorter pedal spindles to normalise one's Q factor.

Aye, I've seen that too. But, that is likely to be for a very small number of pedal models, likely the most popular shimano or look pedals. Which is fine, if you ride with road clipless...

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

Porkins

  • Formerly Nick H. And a long time ago etc, Eurostar
Re: How much power?
« Reply #36 on: May 31, 2018, 09:51:10 pm »
Maybe drop them a line to say what pedals you use. It can't be that hard for them to source spindles if they plan ahead.

simonp

  • Omnomnomnipotent.
Re: How much power?
« Reply #37 on: May 31, 2018, 10:00:10 pm »
SRM are entering the pedal power meter market in a partenership with Look. It’ll be the most expensive option.

Porkins

  • Formerly Nick H. And a long time ago etc, Eurostar
Re: How much power?
« Reply #38 on: June 01, 2018, 05:45:33 pm »
I'd love to see the power meter equivalent of that wind-tunnel testing of luggage and mudguards...

Which testing? Do you mean Bicycle Quarterly? I wish I could get hold of their back issues on the subject.

Kim

  • Timelord
Re: How much power?
« Reply #39 on: June 01, 2018, 05:57:07 pm »
I'd love to see the power meter equivalent of that wind-tunnel testing of luggage and mudguards...

Which testing? Do you mean Bicycle Quarterly? I wish I could get hold of their back issues on the subject.

I think that was the one.  ETA: https://janheine.wordpress.com/2012/05/02/aerodynamics-of-real-world-bicycles/

I'm thinking fat bloke winching up a hill on a sturdy hybrid.  Typical loaded tourist.  Complete novice cyclists.  Children of assorted ages.  Basically, the sort of cycling that isn't sport so doesn't tend to get SCIENCE applied to it, but it would be interesting to see typical power figures for.


(This inspired by a conversation some years ago by a friend at the more extreme 'type 0' end of the sysadmin build spectrum[1] who'd recently taken to commuting by bike.  I posited that I might be twice as fast as him up a hill, but he's probably doing way more work than I am.)


[1] Unisex spaceadmins come in two main body-shapes, referred to as '0' and '1' respectively, on account of the physical resemblance to the digits.
Careful, Kim. Your sarcasm's showing...

Porkins

  • Formerly Nick H. And a long time ago etc, Eurostar
Re: How much power?
« Reply #40 on: June 01, 2018, 09:53:40 pm »
Perhaps I want a meter for similar reasons. E.g. how much difference does it make being on the hoods instead of the bar tops even at 10 mph on a touring bike with relatively high bars? It might be infinitesimal but I still want to know.

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/ And I want to see if one can gain by using a tail pack to clean up the airflow at touring speeds. And to measure the gains to both riders when one is on the other's wheel.

When I've got some numbers I can refine my notional design for the Ultimate Touring Bike, which will see the light of day when I win Euromillions.

Eta: have you seen this? http://www.cyclingabout.com/speed-difference-between-panniers-bikepacking-bags-aerodynamic-testing-results/

Samuel D

Re: How much power?
« Reply #41 on: June 01, 2018, 10:01:00 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.”

What prevents the bicycle from accelerating until no tailwind remains in this hypothetical scenario?

Re: How much power?
« Reply #42 on: June 01, 2018, 10:08:28 pm »
This thread has prompted me to put an order in for a pair of IQ2's.  I've long fancied the idea of powermeters but been put off by the cost and lack of interchangeability.  These answer both those issues and worth a punt IMO.  I'm not in any particular hurry  ;)

Karla

  • car(e) free
    • Lost Byway - around the world by bike
Re: How much power?
« Reply #43 on: June 01, 2018, 10:12:53 pm »
Perhaps I want a meter for similar reasons. E.g. how much difference does it make being on the hoods instead of the bar tops even at 10 mph on a touring bike with relatively high bars? It might be infinitesimal but I still want to know.

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/ And I want to see if one can gain by using a tail pack to clean up the airflow at touring speeds. And to measure the gains to both riders when one is on the other's wheel.

When I've got some numbers I can refine my notional design for the Ultimate Touring Bike, which will see the light of day when I win Euromillions.

Eta: have you seen this? http://www.cyclingabout.com/speed-difference-between-panniers-bikepacking-bags-aerodynamic-testing-results/

He's using an awful testing protocol.  If you want to do better, Google "Chung test".  Note that you won't be able to measure infinitesimal differences though, and getting down to a few percent resolution will still take a fair bit of work. 

I did thoroughly intend to Chung test my touring setup for this trip, but it was one of many things that ended up being sacrificed to the deadline gods :(

Porkins

  • Formerly Nick H. And a long time ago etc, Eurostar
Re: How much power?
« Reply #44 on: June 01, 2018, 10:59:33 pm »
Thanks, that's fantastic info!

Just noticed that IQ2 is offering advance booking of notional Shimano pedals with 10mm shorter spindles, at triple the typical price of a standard pedal. FFS. Please somebody tell me my maths is wrong. An XT PD-M8000 is €105, an Ultegra PD-R8000 is €153. https://www.indiegogo.com/projects/cycling-power-meter-at-a-breakthrough-price-bluetooth-sports#/

jiberjaber

  • ... Fancy Pants \o/ ...
  • ACME S&M^2
Re: How much power?
« Reply #45 on: June 02, 2018, 09:49:33 am »
Thanks, that's fantastic info!

Just noticed that IQ2 is offering advance booking of notional Shimano pedals with 10mm shorter spindles, at triple the typical price of a standard pedal. FFS. Please somebody tell me my maths is wrong. An XT PD-M8000 is €105, an Ultegra PD-R8000 is €153. https://www.indiegogo.com/projects/cycling-power-meter-at-a-breakthrough-price-bluetooth-sports#/

Your maths are probably missing the cost of the "10mm shorter spindles" given its not what they've gear up for initially so they may be covering the risk of making them within the price.  If its a manual job rather than some sort of automated production line approach, then it could well be 3x the cost.
Regards,

Joergen

Re: How much power?
« Reply #46 on: June 05, 2018, 11:49:05 am »
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?

quixoticgeek

  • Mostly Harmless
Re: How much power?
« Reply #47 on: June 05, 2018, 01:04:38 pm »


It's interesting when you do the maths on how much energy is needed to get up a hill. If you're doing a 1000m ascent, at 10%, at 10kph, and weigh 70kg, your looking at putting out 250w for 1 hour. Or 3.57w/kg. That's well into trained person territory for power outputs.

Gives some perspective on how good some riders are when you see their straps times...

J

Ps, to. Maintain an Audax minimum of 15kph, on the same Hill requires 380w. Or 5.2w/kg...
--
Beer, bikes, and backpacking
http://b.42q.eu/

simonp

  • Omnomnomnipotent.
Re: How much power?
« Reply #48 on: June 05, 2018, 01:39:35 pm »
This is why I got dropped on the club run in Sunday. I’m not going to climb at 380W for long.

Once I gave up and did my own thing I was able to work harder on average because able to pace myself effectively. Got some PRs as well.

The above may have something to do with the fact there were only 5 people on the ride.

Re: How much power?
« Reply #49 on: June 05, 2018, 01:43:57 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