Power Meters

[amaferanga]

I've had a stages for a couple of months, its my first experience of using power so cant comment on how it compares with other powermeters but its been bomb proof so far I've had absolutely no problems. I bought it directly from the US so cost me £500. With respect to the L/R thing I must be lucky as I recently had a threshold test done on a watt bike when starting with a coach and my split was 50/50 over the entire test.

That your L/R balance was 50/50 on a Watt bike for that particular test doesn't mean you'll always have 50/50 though. And the bad news is that with the Stages you'll never know how much error there is due to an imbalance. Could be insignificant (to you) or it could be very significant. Remember that even a fairly small 3% imbalance results in a 6% error in power which is huge compared to proper power meters like PowerTap, Power2max, Quarq and SRM.

If you can afford a Stages then you can afford a proper power meter such as powertap or power2max.

 

[VamP]

For someone looking for simple power, with Ultegra (or similar) on 2 bikes, Stages would be ideal. £600 for one shared unit or £1200 for two bikes kitted out. Cheaper than Vector for 2 Stages units. I have Dura ace, FSA and Campag Chorus carbon so not really an option for me.

Ideally i would have an SRM on every bike and on the new TT bike that should be mine for next season. That would result in some bad credit and divorce so realistically something like vector as one unit for a few choice bikes seems the best way to go.

@VamP - yeh race wheels could have powertap fitted but then i am very keen on power for training too.

If anything, you want PM for training more than racing. My PM is the G3 on a A23 32H rim, which is a really solid training set up. I can race road with it, with a small performance trade off to my race wheels. I am going to get wheel covers to convert it to a disc wheel for TTs for next season. I can also ride CX with it (in the less extreme weather races), as it will happily accept CX tyres.

It can be useful to have power while racing but TBH, mostly for post race analysis. For TTs there is clear pacing advantage to having PMs.

From the money POV, a G3 wheel with carbon wheel covers will cost you about the same as a good tubular carbon disc wheel, so if you're serious about TTs that is a totally viable alternative.

 

[ziggys101]

That your L/R balance was 50/50 on a Watt bike for that particular test doesn't mean you'll always have 50/50 though. And the bad news is that with the Stages you'll never know how much error there is due to an imbalance. Could be insignificant (to you) or it could be very significant. Remember that even a fairly small 3% imbalance results in a 6% error in power which is huge compared to proper power meters like PowerTap, Power2max, Quarq and SRM.

If you can afford a Stages then you can afford a proper power meter such as powertap or power2max.

But why does it matter if its 6% or even 12% out if its the only powermeter I use, its about consistency if I make a 10% improvement its still a 10% improvement and it have proved to be very consistent (see DCRainmaker)

 

[VamP]

But why does it matter if its 6% or even 12% out if its the only powermeter I use, its about consistency if I make a 10% improvement its still a 10% improvement and it have proved to be very consistent (see DCRainmaker)

There's much debate on the accuracy versus precision aspect of PM's. This thread is a good example. Dr Chung makes some very good points.

 

[amaferanga]

But why does it matter if its 6% or even 12% out if its the only powermeter I use, its about consistency if I make a 10% improvement its still a 10% improvement and it have proved to be very consistent (see DCRainmaker)

The problem with Stages is that since it only measures left leg power and L/R balance varies for most people then you can't get that consistency. And why waste money on something that won't give reliable data when you can have a power meter that gives reliable (precise AND accurate) data for around the same money?

If Stages was a few hundred quid I'd agree that it's worth a punt as a toy, but it's serious money at over £600. Anyone who buys the more expensive crank options is just crazy.

 

[Zofo]

Here's another excellent review for Vector:-
http://road.cc/content/review/94115-garmin-vector-power-meter-pedals

There is so much more functionality with this when paired with a Garmin head unit. Future firmware updates will give data on Pedal Smoothness, which is a measure of how even your pedalling stoke is over one revolution and Torque Effectiveness which is a measure of positive and negative power-ie how much your are pushing down /pulling up.
Bit of a no-Brainer really, I'm off to buy them!

 

[amaferanga]

That sounds impressive I guess, but is there any evidence that this information is of any use? No point in wasting time getting a smooth pedal stroke if that doesn't improve your performance. Remember that Garmin want the Vector to stand out so of course they're going to talk up these metrics, but I'd want to see some independent experts say something about their usefulness. So I certainly wouldn't agree that it's a no brainer.

 

[Zofo]

Looks like there's a sizeable back order for these already-hardly surprising considering the reviews. Latest estimates are for deliveries back end of the month, I've ordered mine from here:-
http://www.cyclepowermeters.com/gar...m-1023-p.asp?gclid=CKyG3byd7rkCFSTJtAodBw8A8Q

 

[amaferanga]

Great, now what about these new metrics that you were talking about? Are they just gimmicks or will they make me a better cyclist?

I think I'll stick with my Power2max that cost half as much as the Vector.

 

[Mr Haematocrit]

That sounds impressive I guess, but is there any evidence that this information is of any use? No point in wasting time getting a smooth pedal stroke if that doesn't improve your performance.

Well the watt bike which is endorsed by British Cycling and used by them and Team Sky measures the smoothness of the pedal stroke.
http://wattbike.com/uk/blog/post/whats_in_a_pedal_revolution_wattbike_has_the_answer

Team sky also work extensively on pedaling smoothness and believe this is related to efficienct technique and state that climbing out of the saddle is not desirable because ..You have to put a lot of power down the front end of the pedal stroke which has a negative effect on the smoothness and balance of your pedal technique. Having a good pedal technique means you can produce more power for the same physiological effort (HR).
http://wattbike.com/au/news/post/tr...ciple_of_specificity_and_climbing_efficiently

The Garmin vectors produce a lot of the same data sources as the British cycling endorsed watt bike

 

[Zofo]

Great, now what about these new metrics that you were talking about? Are they just gimmicks or will they make me a better cyclist?

Its obvious just watching how the pros pedal that they are applying power in a very smooth and even distribution throughout the pedal stroke. If the Vectors are going to be able to show a real time read out whilst I'm on the turbo then I would start to "feel" the correct action.

 

[VamP]

Its obvious just watching how the pros pedal that they are applying power in a very smooth and even distribution throughout the pedal stroke. If the Vectors are going to be able to show a real time read out whilst I'm on the turbo then I would start to "feel" the correct action.

It might be obvious to you, but virtually all authorities on cycling performance agree it matters not one iota how you deliver your power, so long as you deliver it.

 

[Mr Haematocrit]

After back to back testing with my SRM and Vectors, I find that I am getting repeatable and comparable results.
As such I have sold my SRM and now have an additional set of Vectors...



The reasoning for this is simple, they produce consistent results which are comparable to my SRM figures, they are lighter, they do not need to be returned to the manufacturer when the battery needs replacing, they are easier to swap between bikes and will continue to evolve through software updates.
I will likely replace all my power meters in time with the Vectors, Im very happy and impressed with them.
I am even going try to modify a pair for the MTB

 

[Pedrosanchezo]

Great, now what about these new metrics that you were talking about? Are they just gimmicks or will they make me a better cyclist?

I think I'll stick with my Power2max that cost half as much as the Vector.

Well the watt bike which is endorsed by British Cycling and used by them and Team Sky measures the smoothness of the pedal stroke.
http://wattbike.com/uk/blog/post/whats_in_a_pedal_revolution_wattbike_has_the_answer

Team sky also work extensively on pedaling smoothness and believe this is related to efficienct technique and state that climbing out of the saddle is not desirable because ..You have to put a lot of power down the front end of the pedal stroke which has a negative effect on the smoothness and balance of your pedal technique. Having a good pedal technique means you can produce more power for the same physiological effort (HR).
http://wattbike.com/au/news/post/tr...ciple_of_specificity_and_climbing_efficiently

The Garmin vectors produce a lot of the same data sources as the British cycling endorsed watt bike

I done a fair bit of work over the winter in this area - pedalling efficiency. Single leg efforts to working on the stages of the pedal stroke. Even in its most simple form, the push and pull can improve technique, performance and delay fatigue by utilising different muscle groups. A lot of this was done from feel and at times was hugely frustrating. Having individual pedal/power data during and post ride, would have been so helpful.

If the Vectors perform as claimed, then they will open up new levels of training for any willing cyclist. No one has to use them and others may prefer crank based or hub based power, some no power at all. Those who see the Vectors as a step up from the conventional PM may find that they wonder how they did without.

 

[Pedrosanchezo]

It might be obvious to you, but virtually all authorities on cycling performance agree it matters not one iota how you deliver your power, so long as you deliver it.

Are you sure VamP? Delivering power is one thing but delivering it consistently for a duration is another. Pedalling efficiency is not a myth, it is in the interest of every competitive cyclist to find out how to pedal most efficiently. Just as with something like pre ride nutrition - you don't have to eat wisely before a ride or race but you could improve performance by doing so.