POWER METER UPGRADE

Once we committed to the power meter addition it wasn't long before it became a reality.

A new Garmin Vector S pedal based power meter is now on the bike!

GARMIN VECTOR S

GARMIN VECTOR S INSTALLED

Nat will try it out over the next week while we wait for the rest of the parts for the remainder of the upgrades.

How did all of this come about?  Well the Power meter has been in the back of our minds for a while so we had been doing some homework along the way.  I purchased a power meter for my TT bike 12 months ago so had a good idea of what was available.

A great place to start was the DC Rainmaker Power Meter Buyers Guide and since he has done such a great roundup of all the options there I will mostly discuss the options that worked for my specific application and how I came to those conclusions.

Due to the myriad of options available I had to narrow down the selection somewhat, so start by listing out the current criteria that affect our options:

• Crank Bottom Bracket: BB30 30mm shaft
• Crankset: FSA Gossamer
• Crank Hub: Integrated into crank arm
• Crank length: 165mm
• Shimano SPD Pedals and Cleats
• Compatible with Garmin Forerunner 910XT ANT+ Wireless
• Compatible with Training Peaks Software
• Minimum cost
• Minimum reconfiguration of the bike to install
• Reliable and repeatable

We also needed to ask "What are we really going to use this training tool for?"  The main features we need are simplified to the following:

• Display power data on the Garmin 910XT while training and racing
• Get Power Data into training peaks
• Use Training Stress Scores (TSS) to track training loads
• Set specific power targets during key training sessions
• Provide Nat's Coach, Karen Short, with feedback

I could go on for a while on this topic but it is already well documented in Joe Friel's Blog  and the Training Peaks Blog which has contributions from Joe Friel & Andrew Coggan.

So Nat's needs are for a basic power meter that will really complement the Coaching and training resources she is already using.

The more advanced features such as Left/Right power split, pedal smoothness are features that won't get used and will blow our budget which we are hoping to keep under $1000 so our first though was just to grab a basic Stage power meter which is built into the non drive side crank arm.

So the process went something like this:

• Found a stages power meter crank arm to suit the FSA crankset
• Not available in 165mm
• Found other Stages cranks in 165mm, e.g. Shimano Ultegra
• This added $300 - $400 for a matching crankset and 24mm spindle adapters
• Investigated crank spider style power meter's such as Quarq and Power2Max
• Basic power meter units alone were over $1000
• Still required a replacement crank  -> $300 - 400
• Maybe something will pop up second hand
• 165mm and BB30 is about the least common combination

Thats when we stumbled across a seemingly cheap Garmin Vector pedal based power meter.  It seemed too good to be true but closer inspection revealed it was their budget single sided version which basically halved the cost.  It was also a run-out of the first generation which had recently been superseded by the Vector IIS.  At first I was sceptical, it seemed too good to be true so keen to grab a bargain I focused my effort on the Garmin Vector S:

GARMIN VECTOR S PROS:

• Simply replaces the pedals to provide power
• Similar price to Stages
• Meets our basic criteria above
• Available at a good price from a local supplier

GARMIN VECTOR S CONS:

• I had this idea they were unreliable and troublesome
• Need to change from Shimano Pedals to Look Keo pedals
• Only reads of left side pedal
• Seemed too good to be true

So I went back to DC Rainmaker, Garmin forums and whatever I could find on the net to satisfy myself this power meter was going to fit the bill.

Reliability:

• There were a few complaints on the Garmin forums, almost all caused by careless installation
• The pod housings can crack if the pedals are changed between bikes too often
• Garmin since improved the pod to a stronger forged material
• Spare pods are available for around $100
• In the install manual I could see spacers and steps that people could muddle up
• I was confident I could install these carefully and don't intend to remove them often
• Installation went without a hitch and they are operating perfectly for now

Changing pedals:

• Nat was using Shimano SPD pedals
• Look Keo look and operation are very similar
• No real concerns here in our case
• Once they arrive we found the Look pedals to be nicer
• The Look cleats were similar but smaller and with a few pen marks were re-aligned the cleats
• We will need to buy another set of pedals for Nat's other bike (~$80) 

Single sided budget version

• No different to Stages which measure off the left arm only
• Nat had been tested during her bike fit and her left/right split % was pretty close
• We can purchase the upgrade pedal later
• Adding the 2nd power pedal only adds functionality we don't really need at this stage

So after a couple of days of deliberation I was satisfied that the Garmin Vector S power pedals would suit Natalie's needs.  An added bonus was we sourced the locally and they arrived the the next day which gave us the opportunity to install and test them before we strip the bike down for the Di2 install work.