Thinking about arcs tonight. Graceful, beautiful arcs.
It started on this evening’s trail jaunt. After being snagged into a mildly unnecessary meeting today, I missed out on connecting with a visitor to this fine region. That got me a bit grumbly for a while, but maybe it just wasn’t in the cards for this time. The meeting pushed back the more pertinent projects that I should have been addressing, which in turn had me working later than I’d planned. Suddenly realizing that it was later than it should have been, I blasted away from work and punished myself a bit to hustle home. For the evening yoga class.
Yes, I was hurrying and stressing to get to yoga on time.
There’s a message in there somewhere.
Got home to find that my wife had learned that our instructor would not be there, and the Evil Twisty Lady from Tuesday night would be leading the class. E.T.L. had appeared at the last class, covering for the regular person. The regular instructor is very, very good - intutive, careful, aware and mindful that she is leading a beginning class. E.T.L. had us doing moderately advanced stuff right out of the gate, all of which seemed to morph into some type of spinal twist. This left me all too aware of a bad spot in my neck which hadn’t hurt for a while, but was now.
Which meant that I was wholeheartedly in favor of my wife’s decision to skip the class.
And I managed to get a little grumpy then too, as it would have been better to work another half hour, finish things and not get all kerfuffly trying to be home at a specific time. Of course, it then dawned on me that I could dump my bag, put on some arm warmers and head back out again. This helped me to be less of a grump. Which, of course, allowed me to see I’d been more of a grump than was necessary.
Luckily, grumpiness whithers under scrutiny and laughter.
So, I hit the road, aided by a tailwind and the solar power of the descending sun. Was thinking that a loop around the point would be nice, but upon reaching China Camp, it was obvious that the Jack Brown tires were clamoring for a little trail dust in their teeth. By this time the grump arc had reached zero again, which meant that for the purpose of the measurement phase, it had ended.
Arcs continued to keep my attention as I rode. The trails have hardened up, and the oscillations of the bike were definite. My body, however managed to float above it, and I found myself thinking about the arc it made as the Quickbeam dropped down into dips and bumps.
I thought about arcs of power and accelleration.
That thought seemed to get at the crux of singlespeed riding in general and fixed-gears on trails in particular. By this time, I was having a grand old time, hitting it hard when line of sight allowed, nipping the crux line on smooth, fat tires, feeling the bike move to hug the trail as I hovered above it, offering all manner of body english to keep the pedals moving and things heading the right way.
The Quickbeam has a 14 tooth fixed cog, so with the large chainring, it measures out at around 77 gear inches. This means that there are times when my cadence is probably, I don’t know, around 12 or so rpms. (For example, with a quick visit to the Sheldon Brown Gear Calculator, 40 rpms in this gear is slightly more than 9 mph.) There’s plenty of power, but little ability to accellerate.
(As I type this, it seems that there may be a Trail corollary to the “Climbing Gears” in a fixed system. I’ll have to ponder that some more.)
This became clearer while rolling up on a mixed group of coastable mtb-folk. I’m sure they climbed a bit higher earlier in their ride, and now were happily twiddling away in a refreshing low gear. After working my way past the tail end members of the group, the leaders fell into alpha-male mode and protected the honor of those I had passed by increasing the pace. (Which I completely understood. Who the heck wants to get passed by some dorky guy wearing a sweater riding a smooth-tired road bike with luggage on it and a bottle in a frame mounted cage. Plus, I’m still running fenders with green tweed flaps.) They moved away quite easily at first, maxed out their spin in the 36/32 combo and bought a couple of gears with their clicky bits.
The topography helped me out a bit by easing slightly down. This is where the acceleration arc abruptly changed. There’s a magic point where speed and cadence suddenly give way to some weird turbo boost and I went from 20 yards off their tail to contemplating the hairs on the back of the other rider’s neck in a quick hiccup. Just another example of what the first person I ever knew who rode singlespeeds told me, “On a singlespeed, you are either going very slow or very fast.”
They veered off and took to the road. I kept on the trails and dirt, playing in those combinations of speed and cadence that suddenly gave acceleration. Playing is good.
I just love that part of the arc.