Wednesday, February 2, 2011

Kneequilibrium and The Varieties of Fixed Gear Experience



The locus of ceaseless bending motion

After riding the fixed gear about 55 miles this weekend, a some ideas gelled about what is easier than I thought it would be for me to adapt to with no freewheel, and what is harder.

Easier, fun even: starting, spinning, stopping, standing, hills, bumps, corners, sprinting.

Harder, still fun to explore though: if the bike isn't set up just right, and sized just right, and / or your technique has flaws, riding a fixed gear gives you direct feedback about what's wrong, and doesn't give you the normal breaks during coasting to rest a bit or relax. In particular, the constant rotation of the pedals compelled me to shift around and make many adjustments to just about everything until everything, particularly my knees, felt right. I am talking about small adjustments that added up to tangible differences. My knees felt great after the rides. But at certain points in the middle, they started to let me know, "You are not doing it right." At that point, I would try something different, varying the forces in my pedal stroke, shifting my weight forward or back a little, checking the angle of my legs and ankles, and so on, until it seemed to feel better, and then it was better. 

I guess I'm saying that on a fixed-gear, since you can't shift gears or coast, when you need to make adjustments for comfort and efficiency, you find new things to adjust in your technique in order to achieve "kneequilibrium", the combination that leads to the knees working inside some optimal combination of force and timing that feels right. That's how it felt out on the canal path, anyway.

My kneequilibrium establishment mechanism

I finished out the Sunday ride with a hard push for the last three miles, to see what it would feel like to spin more or less as fast as I can on this bike without bouncing. With a 42x16 gear combination that doesn't yield a super-fast forward speed, somewhere around 23 mph in the 110 rpm range, [yeah I know, not very impressive, I ride for love not glory] and it's smooth cadence, not power, that becomes my limiting factor in Flatland. Which leads me to a couple of further conclusions. Since it's better technique with higher cadence, and not higher forward speed, that I'm seeking, I finally might have to mount one of my cycle computers on this machine to collect some better numbers about what's going on. And more practice might be better for my knees, my efficiency, and my overall ride. Listen to me. Maybe I'll just keep spinning fast as makes my knee-go feel good instead. Get up. Go ride. 

7 comments:

  1. Agreed on all points. Finding the ratio that gives you just enough speed while still taking care of your knees (especially on older or achy ones like mine) can be tough at first.

    My fixed is 44/17 which on my bike works out to 69.3 gear inches... I'm not going any higher. Knee-go trumps all.

    ReplyDelete
  2. I don't know . . .23 mph sounds pretty darn good.

    ReplyDelete
  3. Interesting.
    I still got that single speed conversion kit around here somewheres.
    I need an interim project.
    Holding 23 for 3 is quite impressive.

    ReplyDelete
  4. Glad your enjoying it. As limom says 23 for 3 is pretty good,

    ReplyDelete
  5. RANTWICK I may need some fixed-gear commuter bike setup advice soon! Need to check out some of your old posts. Fenders, rack, wider tires I am wanting.

    JK, limom, Trevor: I felt good riding at the pace I was riding. I should probably stress it was an estimate and I should be less specific about that stuff until I put a speedometer back on the bike. I used to ride with one all the time and have a pretty good sense of my cadence, though, so I don't think I'm completely far off, anyway. In the back of my mind was this book I got for Christmas, "Ride Fast," a training book that sets a goal of a three mile time trial at 25 mph. If I did that, measured accurately, it would be something to blog about I guess. I'm not sure going faster is my goal, though. I think staying fit and riding happy is what I want more.

    ReplyDelete
  6. Very interesting comments. Someday I'll try the fixed gear thing.

    ReplyDelete
  7. Apertome, do it man! As much as you ride you should give it a try.

    ReplyDelete

Please feel free to comment here, almost anything goes, except for obvious spam or blatantly illegal or objectionable material. Spammers may be subject to public ridicule, scorn, or outright shaming, and the companies represented in spam shall earn disrepute and ire for each occurrence.