Monday, June 13, 2016

Equipment - Longer Cranks (175 mm, again)

I was thinking that I'd have a race report from the Nutmeg State Games right around now but I ended up not racing. It wasn't for any reason other than I was a bit bonky when I got out of the car, it was about 55 degrees, and it was pouring rain on and off. In fact the rain decided how long I stayed - I got out during a lull, took refuge in the Expo tent during a downpour, then ran back to the car when the rain took a break.

I had a number of other things going on as well. My Pops has a limited time window that he can be away from home (and all the easier/nicer facilities and supplies we have at home). I could do about 90-120 minutes onsite but any more than that would be tough. With the races running sort of late (45 minutes?) I'd have been well outside his "window of availability" if I had raced.

Another thing that tipped the scaled towards "maybe next week" was that I had just put the 175 mm crankarms back on the bike.

I did it sort of by accident, if you could say it that way. I had just installed a new battery in my SRM spider, meaning I just soldered a battery into the spider. The powermeter worked for a day then went haywire. I assumed I'd screwed up the soldering and the thing shorted or something. So I took the cranks off, meaning both crank arms (yes, I removed the left arm for some reason), removed the chainrings (they hold the SRM "cover" in place), and opened up the SRM. Measured voltage at the battery terminals as well as the circuit board, on the other side of the solders.

3.58 volts, for both.

Which is what it was when I soldered the battery in place. So my soldering job was okay.

When I reassembled things I put the 175 mm crank arms on there, because I had them sitting there and on some spontaneous choice fate thing I just grabbed the 175s when I went to put the left arm on the bike.

I put the right 175 mm arm on the spider, bolted on the chainrings, and stuck that on the bike. Adjusted the N-Gear Jump Stop super aggressively (it rubs in the 39x23, 39x25) so I'll never drop a chain off the small ring.

Put the Exustar pedals on.

I lowered the saddle 5 mm to adjust for the new, lower bottom dead center pedal point. I didn't bother moving it forward because the ISM Adamo saddle is so versatile a few mm fore/aft isn't a big deal.

The rest of the bike I left alone.

I did a short spin, a panic ride, like cramming for an exam, Friday. I hoped that my legs would adapt to the bigger circles. My legs felt all out of whack, muscles straining in an unfamiliar way, super quick to fatigue. I didn't go hard and after a very short ride (it wasn't even 11 minutes) I stopped.

After all that, with the crank change, I just wasn't feeling it for Nutmeg.

Sunday, though, I decided I needed to ride. I did a couple hours on Zwift. I immediately felt better, my legs loping around in circles, turning a big gear over pretty easily. Last Wednesday I was absolutely struggling to hold 170w (in Zwift world).

Sunday? 200w was okay, although my heart rate started to climb when I tried to hold a bit higher level.

Because Zwift penalizes me a bit because of the calculation, I was riding about 30-35w harder than what Zwift said.

After getting an aero boost I decided I'd do a sprint. For me sprints are a focused effort, I roll pretty easy until I get to the sprint, then after I do all I can do to keep my avatar from stopping. See, if I soft pedal at 8 or 10 rpm, the avatar just stops. The sprint wasn't a record effort for me but for being on the longer cranks, not training much, having done two races this year, somewhere around midnight, it was a really good effort for me, within 5/1000 of a second of my last 30 days (Zwift tells you that) but more significantly I put down better power numbers.

Because Zwift sprints are time trials, because it's impossible to jump at exactly the same place and at the same power, and because other riders affect your time (drafting etc), there are two parts to a Zwift sprint: Power and Time.

Note my top times from the last 30 days on the left side of the screen.

My time was okay, 23.07. My best time in the last 30 days was 23.02 but I might have passed someone in the sprint or jumped a hair earlier or something.

However, on power... I gained about 100 watts for my 20 second peak. I didn't jump super hard because I knew I had a 25-30 second effort in front of me, but my peak was still 100w higher than what I've been hitting with the 170s.

When I raced the last two weeks I felt like I was holding my breath the whole time. I couldn't get moving, couldn't do the little punchy efforts I can usually do. I know I'm less fit but it seems that I'm not using the 170 cranks properly, or maybe I'm not optimized for it. The 170s will naturally load the aerobic system more, forcing me to spin. The 175s emphasize lower pedal speeds and torque, so it's more muscular stuff. I think I'm always going to be okay on the muscular stuff and always going to be a bit lacking (or a lot lacking) on the aerobic stuff.

I took today off from the bike but it's looking promising for tomorrow's Tuesday Night race. I hope to test my legs on the 175s then.

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