? for Rich Stanbaugh inre % time in gears
Hey Rich Stanbaugh
in your podcast with Coach Rich you spoke about time in particular gears which helped you pick your cassette for Raliegh. I was wondering how you got that data. Coach R expressed interest in obtaining that info but never asked you.
Please enlighten us
thanks,
Rob
0
Comments
I wrote a spreadsheet to make a "best guess" of the required gear ratio based on the cadence and the speed of each sample recorded in my Garmin File and on my wheel size. From this, I matched to the closest gear ratio on my cassette. Had to make a couple of assumptions to account for being "spun out" on descents and to account for gear solutions that I can't use (cross-chained). When I had all the gears matched to samples, I estimated the time in each gear. Each Garmin sample is 1 second, so I treated them all equally. Here are my results from Raleigh 2014:
In 2014, I was setup with 50/34 and 11-28 cassette. You can see that I spent about 29% of my time in the 50 chainring, and the 15t/17t gear. For me, at 90RPM, that is a 3+ mph gap that is right in the sweet sport for my racing (21-24 mph).
Based on this data, I elected to setup with a 12-28 cassette. This cassette swapped out the 11t gear for a 16t gear. Here are the results from my 2015 ride:
As expected, I spent more time in the 12t gear. Some of that (as was some in the 11t gear) spun out. I calculated 2.6% of the time versus 0.9% of the time in 2014. I estimated this by looking at speeds that required cadence > 100 RPM. This additional spinout added to my VI in the hilly sections.
More interestingly - look at the amount of time in the 16t gear. In the 20-mile section of the course between miles 5 and 35, my VI was 1.019 with average speed of 21.7 - right in the sweet spot for this cassette. With the 11-28 cassette, I needed to swing the cadence enough to move over 3 mph in this range. the 12-28 cassette allowed me (I believe) to maintain a steady cadence and shift to adjust to power swings as the terrain changed in this range.
I can imagine 1,000 things wrong with this analysis. I don't think it is perfect by a long shot. But - it was my second attempt to get insight into which gears I uses most on my bike. My first attempt came when I was cleaning my bike and was noticing which gears were dirtiest. For all its shortcomings, I think this approach gave me a better understanding of what is going on.