Power Meter Choices Part 1

Well rather than write screeds in one sitting I have decided to break-up my entry on how I went about choosing my new powermeter, the installation, and headunit.
I am going to break this into three parts with this being the first regarding system choice.

The Options
There were a couple of reasons I decided to update my system. The first was the age and the second was the technology used. My old SRM systems were coming up to about 7-8 years old, and while they were still reliable, the fact that they were wired and used either a square-taper or Octalink BB was becoming a hindrance in looking at new frames.
I already knew the three systems I was going to have a closer look at SRM, PowerTap, & Cinqo.

SRM
This the grand daddy of all the power measurement systems available on the market today and the technology hasn’t changed much since it was originally implemented. The design has been refined and spread across a number of different crank systems from Shimano, FSA, Cannondale, and Rotor.
The biggest developments have been in terms of the head unit. With a progression from the original PCIV which I started off with through to the latest PCVII. Each iteration has been a refinement of the previous, though some would argue that the PCIV’s 0.1sec recording rate was a feature that should have been continued on later models.
My SRM’s were running the PCV head unit which was the last of the wired units supported before SRM changed to wireless with the PC VI. When they made this leap there was no cross compatibility between the systems meaning that a PC VI would not work with a wired system.

The Good
• Proven, reliable, design.
• Easy to setup and use.
• The gold standard in accuracy.
• Service is the best in the industry.
• User calibrated.
• Now USB compatable/ Charging
• 130+hr battery

The Bad
• Price. In market terms SRM’s are overpriced given the technology involved as demonstrated by pricing for Quarq’s.
• Units are sold minus a head unit which is needed to check/ change calibration. Across all power meters, these are the most overpriced component given the technology involved.
• No GPS.
• Head Unit not user customisable.



Powertap
Another power meter I currently own as it is the only viable system available for the MTB. Like most people I have had problems since purchasing it, with it having to go to the USA to be replaced (reason not given) by Saris. And 1x set of dead bearings inside of 4 months on return. Powertaps are cheap in comparison to the other systems available and a lot of people end up purchasing them for this reason. However as mentioned previously the support given by TBA for these is next to none...if you are lucky. I ended up contacting Saris directly when I had problems with mine. Personally if/ when Cinqo get a MTB crank on the market I will be selling my powertap wheel.

The Good
• Cheap, you can purchase two for the price of an SRM.
• Easy to use

The Bad
• Chews bearings
• Cannot be user calibrated
• Next to no support in Australia from the distributor
• Bound to one rear wheel.


Cinqo
The new kid on the block. The system is not common over this side of the world, and after doing some research I found out why. Cinqo produce measurement systems for a number of cranksets, SRAM, Lighting, Rotor, Cannondale basically any crankset which has a removable spider similar to SRM. However the only cranks distributed internationally are the SRAM version. And these are done back through SRAM. So it goes something like this,
Quarq get the cranks from SRAM -> Fit the new spider and send back to SRAM international ->SRAM International then send these out to their distributors in each region -> You get your LBS to contact the countries distributor and purchase them through them.
You cannot buy directly from Quarq if you live outside the USA or Canada....which seems a bit backwards.
So I initially found a cheap on-line seller of the cranks here in Australia, but after a number of emails to Quarq, SRAM USA, the seller, And Monza here in Australia. I worked out that they were not an official distribution channel despite claiming to be. For those interested the only official distributors here in Australia are Monza and Echelon Sports.
In the end I actually found a second hand set from the USA for less than $AU1300....good score.

The Good
• Proven technology- Strain gauges in the crank.
• User replaceable battery- yah no more $AU90 to have the crank battery replaced every 18 months.
• Spider can be swapped to BB30 cranks should buy a new Cannondale Caad 10
• Lighter than current setup
• Integrated BB spindle means it’s compatibles with most modern frames.
• Not bound to a specific headunit, can be used with Garmin, Saris Joule, and SRM (if you get the signal changed.

The Bad
• No local support. If there is a problem it has to go back to the US
• Not easily user calibrated. It is possible but very involved and you probably need to be a computer programmer to do it.

The Unknown
• Reliability- Still a very young system and its long term durability is not known.
• Accuracy- The crank has 20 separate strain gauges to achieve the claimed 2% accuracy vs SRM’s 2, 4, or 8 gauges. Until I started using the crank this was going to be the real unknown as to how it stacks up against the SRM.

Part 2 will follow in a the next couple of days.