Oct 1 I ordered the ANT+ updater for my PowerTap MTB hub. This gizmo upgrades the firmware in the hub such that it transmits on 2 channels: 1 to the power tap computer head, the other channel on ANT+ sport. The ANT+ channel is a semi-open protocol and several devices speak the language. Among them in Garmin’s Edge 705.
I picked up a 705 after this years Canadian affair in which I left behind another GPS unit – doh! The 705 had already caught my eye though because it is ANT+ and would eventually be able to communicate with power transmitting hubs/cranks.
The ANT+ updater arrived last weekend – the update was fast and easy, with a few other wrinkles though – I’ll have those details up on lwcoaching.com eventually. Once updated, the 705 picked up the PT signal immediately – bingo!
Yet…it is not as simple as it seems. The 705 uses an (unknown to me) algorithm to smooth the raw recorded data and in the process the integrity of that data is gone. It baffles me why they take a quality raw data stream and alter it! It essentially takes the good stuff and turns it into less good stuff. It’s really a bigger issue with variable efforts such as occur in road racing and single speed MTBing. Steady endurance rides would probably come out similar. It scrubs about 30% of L6 power from every one of my SS files when compared to the PT CPU.
So heads up y’all. Gizmo integration is just around the corner but ain’t here yet. If you want a 705 to go with your PM it’s best to hold off for now. If you’ve spent $1,500 on your sweet power meter you probably want it to record good data and for now that means stick with the PT CPU in the powertap system.