Power Meters / Powermeters (SRM, Powertap, Quarq, Ergomo, Vector, Stages, power2max, P2M, 4iii, InPower, Cinch)

That, I totally agree with!

Buy a HRM for hundreds of quid less.
So, it lags a bit at the start of efforts. At least it's accurate in its measurement.

Lots of super fast people have raced and won with no electronics. That's the cheapest option.

Buy a HRM for hundreds of quid less.

Thats what I did.

FWIW I had P2M Classic and it was spot on "SRM on budget".

Fast. Raced. Won.

LOL ^

BB30 to BSA conversion:
http://www.7hundred.co.uk/32835/products/rotor-bottom-bracket-bsa30---bb30-to-threaded---steel.aspx?origin=pla&kwd=&currency=GBP&gclid=COyN54nxrssCFcoJwwodRNkOGg

The problem is, that by buying stages you are only measuring power from one leg and then multiplying it by 2. In most cases this is neither accurate nor consistent.

Take me for example... I know from last season that my power balance is c. 50/50 at TT intensity. This would suggest that a stages power meter might be effective for me in those circumstances. However I also know that my power balance wavers from 50/50 under different circumstances and sometimes quite significantly.

Looking at my last few rides I see that my 2x20minute efforts today were 49.8/50.2 and 50/50 respectively, however my warmup was slightly left dominated (51.5/48.5) and my rest period was slightly right dominated (49.2/50.8). These aren't huge swings, and so maybe stages might produce similar data.

By contrast, my last club run was 120 moderately hilly km where I misjudged my recovery from a recent cold and spent the day dangling before being telling the group not to wait and limping home. Over the entire ride, my average balance was 52.9/47.1 however the final few kms where I was really struggling were out at 57/43! Just taking my left leg data and multiplying by 2 would have given all sorts of bizarre readings and would be completely useless!

The average power balance on the club run before that was 56.1/43.9, again with the greatest imbalance coming when I was severely fatigued.

Measuring L/R power balance seems to be pretty pointless from a performance perspective (there is no evidence that I know of that says the fastest riders are most perfectly balanced) but it is interesting data to see how power balance is both different for all different riders, but also how different it is in different circumstances (whether within ride variability or between ride variability).

If you know that your power balance is 50/50 then stages would probably provide pretty accurate data. Even if you know that you have a consistent imbalance across all conditions and circumstances then you could at least get consistent but inaccurate data. But if you are like me (or others that I've spoken to) then you are probably neither of those and in that case stages will be worse than useless.

At least it's accurate in its measurement

Unless Garmin...

Stages ≠ accuracy argument never wins. Thats how they've built their brand and have a world tour team sponsorship. They know that and the USP is 'minimal, cheap and light'.

Sadly cheap is not cheap enough.

4iiii looks decent but 'Murica.

Doesn't work with proper BB30 cranks, only BB386EVO/Rotor long axle cranks. Definitely won't work with an S-Works crankset.

How do you feel about spider based power meters?

I only use Polar HRMs.

Actually, I just realised that's bullshit. I also have a bluetooth strap and lots of powertap ones.

You do know how sponsorship works, right?

I could sponsor a pro tour team if I wanted to.

hippy's Power-o-tronic as used by whoever the fuck takes my money

97% inaccuracy

Eeeew spiders!

said every Brit, in every conversation about living in Australia, forever.

and rightly so

My current power balance is 52.5% right.

My left leg is a bit blah right now.

^ Dont lean!

ok, I take all y'all point, I'll buy a P2M yeez

So, have any of you actually used a gen 1 or gen 2 stages? Like actually used it for an extended period of time, as well as concurrently owning multiple other brands of power meter and had a significant amount of personal experience with multiple brands and generations of power meter? Or, are you just saying they're shit and unreliable because your mate Jeff over heard someone down the pub that was telling his mate Jonny about something he read on the tinternet where some ones mate on a forum owned one and had a bad experience with it?

Which leads to the question where is the data re. you are not a world champ and you get significantly better training results with power rather then HR?

It's not a question of having used it, it's the fact that they're fundamentally flawed and not cheap enough to make it worth it.

So you say, having never used one or having no personal experience of one.

See, training with power is great. But it's only relevant to yourself if you're actually using for training and not just waving watts in the pub.
Really it makes no difference how accurate your power meter is, literally none at all if you're using it for training. What makes a difference is consistency. If it is consistently accurate or inaccurate it matters. As long as it gives the same number for the same effort every time then it's ok. It makes no difference if your power meter is saying 300 and John is saying 330 and Jeffrey's is 390. As long as they are consistently accurate to themselves.

Now, I've used a stages, and I still do. Along with 2 power2max and a current power tap. I've owned 2 gen 1 power2maxes, 2 gen 1 stages, 3 generation 1 powertaps. To be fair, stages were unreliable at launch but I've had no problems with my gen2 and would recommend them to anyone. As long as you are aware that your powertap will always read lower than your power2max or srm and you know to adjust your effort upward or downward to compensate then it's fine. It's no different to a stages reading higher or lower for any given effort as long as it is constant in that reading, and they are.

I know it's popular to hate them, and that's fine if you want to jump on that band waggon but it's simply not true anymore that they're rubbish or a toy. Given that you can pick them up for £380 or what ever online then they are cheap enough, at half the price of both my power2maxes.

I've just had a look at prices, while a power2max seems cheap on the face of it. If you haven't already got a crank, once you include arms, rings, bolts and a bb it's almost twice the price of a stages including a new ultegra crank. Bear in mind you'll end up with a better shifting , lighter crank for half the outlay of a power2max given the euro/pound rate at the moment.

i don't know enough about stages to comment but people worrying about 1 or 2% differences shown in left right balance when their power meter is only accurate to 2% at best is mega lols....

you might be wonky or you might not, or you might be wonky in the other way, the equipment you are using to test yourself isn't accurate enough to say with any certainty...

Only way to find out list for @hippy stages donation so we can find out him using two power meters.

But stages isn't consistent. LR balance changes with effort and fatigue as well as cadence let alone injury etc.

The only time it would be worth while was if you only had a left leg.

As mentioned, the Team Sky argument is meaningless, they are being paid to ride them.

Jeff says they're shit as well?!?! Fuck me. Avoid!

I didn't say that. I said that if choosing shitty power data vs. Good power data and on a budget why even bother with power? Plenty of people use hr and smoke us.