I have no interest in owning one, but am curious as to why they cost so much. Is there some really clever engineering in there or is it just because pro teams/wannabe freds have tons o’ cash?

Lots of R&D involved in making a reliable product.
There are several on the market now, but only a few that are trusted enough to provide reliable results all the time.

relatively low volume scientific measuring equipment is always expensive.

Cos they’re built to be super-accurate and reliable, and have to bung a load of technology in an inconvenient place on the bike (in the hub or on a crank ).

You could probably build something cheaper if you were willing to accept much more error, but I suspect the target market is people who want something that is more accurate than heart rate to train against, so it might not sell well.

Having said that, the polar one is built using a method which is less accurate and less reliable and isn’t so complex from an engineering point of view, so is cheaper. So is the iBike wind-sensor based one.

It also could be because hardware manufacturers are behind the times slightly, basing their designs on extremely low computing power and developing extremely high quality but expensive sensors, whereas in practice, equally good results could be had by using way more complex processing on data from multiple cheap sensors, and processing power is dirt cheap nowadays (although the iBike one doesn’t appear have found the right processing of their particular sensors judging from the reviews).

If you look at HR measurement, we have gear at work that costs from about a quid, to 20 grand, all of which can extract a heart-rate from a person. The one that costs 20 grand is somewhat more accurate and lets you tune what your definition of heart-rate is a lot more than the 1 quid sensor, and requires a whole lot less post processing by a computer.

R&D and a small market. I have a Stages power crank that is great but was expensive (although only half the price of a srm). I also have a powercal and it’s not bad for £80. I’ve run both simultaneously, and for summary info and longer rides and off roading, the 30sec average is fine. Powercal has a standard deviation about half of the Stages (so it has lower peaks and higher troughs).

Now the geeky bit… I do prediction for a living, and am currently working on a better algorithm to predict power from heart rate than the powercal. Essentially a Garmin could give you estimated power from the measurements taken. It won’t estimate your 800w 3sec efforts though!

You’d like to think if they knocked down the price by a 75% then they’d sell more than 4 times as much. Probably not however.

TiRed – Whats this Powercal you speak of? I’d love to know what power averages I’m knocking out on say a 5 minute climb. Not botherered in min and max, really.

Are you saying that this Powercal thingy can provide a fairly accurate average power output over a sustained period of time… for 80 quid?

How does that work?

TiRed – Member

R&D and a small market. I have a Stages power crank that is great but was expensive (although only half the price of a srm).

Are you happy with it?

Reports are that it isn’t all that accurate in the first release. Where did you get it from? I thought it was only for sale within the US still?

It would be interesting for an MTB perspective but it can’t touch the more established products out there by its very design don’t you think?

PowerCal is the cycleops heart rate monitor with an algorithm that estimates power from accelerations in heart rate.

I bought the Stages in the US and brought it home. The first unit didn’t survive some bad weather. The replacement has been fine.

I wouldn’t worry about absolute callibration, any measurements are cross referenced against past measures on the same device. And swapping it out is very fast.

For mtb riding, i’m happy with powercal. For road racing, i used the Stages yesterday and it helped.

R&D and a small market. I have a Stages power crank that is great but was expensive (although only half the price of a srm). I also have a powercal and it’s not bad for £80. I’ve run both simultaneously, and for summary info and longer rides and off roading, the 30sec average is fine. Powercal has a standard deviation about half of the Stages (so it has lower peaks and higher troughs).

Stages is about the cheapest (potentially) accurate one out there, more like 20% the cost of an SRM!

£523 according to Barclaycard for the Ultegra crank. Plus a head unit (Garmin 500). They probably won’t be coming to the UK for 8-12mo though. For constant turbo trainer use and commuting, I’ve used the PowerCal to good effect. And to be honest, I felt that accuracy against other meters is over-rated. Consistency is more important. I may try and borrow a PowerTap for three way calibration, just for fun – my puny wattage didn’t trouble anyone in the final sprint at yesterday’s Surrey League 😳

The issue with the Stages, as you’ll know, is that it’s about the only system to only measure one side. So as long as your balance is equal, or at least consistently lopsided you’ll be fine. If however you equalise at threshold, or ‘swap’ your dominant leg at higher power outputs it’ll be less accurate.

Considering its only £150 or so cheaper than something like a Power2Max Rotor 3D, which does proper L/R split I’m just not convinced.

I did email them before their launch, they’re not coming to the UK until next year, but seeing as they’ll no doubt go to $:£ prices I’m not sure that’s much of a goer anyway. IMO their advantage is that they’re a good chunk cheaper than PowerTaps, Quarqs, SRMs etc.

Two assessments on a Wattbike, coupled with 80-100 miles a week of riding fixed, showed that my pedal stroke was very even. The biggest selling point for me was the ease of swapping between race bike and other bikes, coupled with the absence of weight compared with a low-end powertap (no race wheels/training wheels dilemma). They plan on offering them as OEM, and I suspect that takes priority over EU supply.

As for reliability, well the jury is still out, but I was probably unlucky. If you really want one, then they can be sourced. Email me privately,