Friday, September 01, 2006

Bikes, Bikes, Bikes

Ahh, the end of summer. When a middle-aged man's fancy turns to thoughts of... biking!

On most clement days I've been biking to work. After my crash earlier this summer I got my bike patched up. My legs are mostly healed up from the obvious damage as well as some more hidden damage. The chainring scars are probably permanent, but they are superficial; what was worrying me more was the lumps in the muscle of my quads near the knee and the burning sensation to the left of my right kneecap. There must have been quite a bit of hidden damage! The lumps are gone and the knee feels considerably better; my quads have expanded so much that I've got some new stretch marks. I've always had a huge difference between strong muscular legs and long skinny arms; it is almost laughable, despite my attempts at weight-training my upper body over the years. That's probably why I feel like biking comes quite naturally.

The bike I use for commuting, as well as occasional beginner to intermediate trail rides, is a Marin Bobcat Trail from around 1998: an aluminum-frame, relatively light, relatively bare-bones mountain bike. I think it was originally about $400. After my first trail ride and the pain it induced in my carpal-tunnel-damaged wrists, I started wearing padded biking gloves with a cut-out chanel to take pressure off the median nerve, and added a front shock and bar ends; after I started using it to commute I changed out the stem and handlebars so that I have a slightly more upright position when I ride.

After the crash I had the bar ends, which were bent up, taken off, and had a new harder seat added, with the newfangled sculpting to try and take pressure off of parts that tend to lose their circulation and go numb. I also changed out the tires after one of them blew out due to dry rot (it was old!) It's been a great bike and I intend to keep it as long as I can. I would only replace it if I started regularly doing some really hard-core trail riding, which I don't envision.

My second bike is a 1999 LeMond Alpe d'Huez. At the time it was the most expensive thing I had ever purchased, at around $1,200. This bike is optimized in a completely different direction: it's made for serious road rides on smooth pavement. If I take it for a short ride, it seems like I only have to pedal very occasionally; it has such low rolling resistance that it seems like I am coasting most of the time. In fact, I am! This also means it is much harder to get a cardio workout on the LeMond -- I have to go much farther, or find some long, steep hills.

The LeMond has an absolutely gorgeous design, with a stainless Campagnolo group that is still in great condition. It came with clipless pedals, the kind you use with bike shoes, but I had never used those so I had pedals with toe cages put on; I know that's not very hard-core, but so be it; my longest rides tended to be less than 40 miles, which isn't much distance for a bike like that (less than three hours). Maybe some day I'll switch.

I started to break down the cheap seat it came with and so put on a hard Bianchi saddle. I had a set of profile aero bars on it and those were fun, but I didn't use them very often, so I just recently took them off and put them in storage for possible use later. I swapped the tires for new ones since they were also getting kind of old and crumbly; I also rotated the handlebars into a slightly higher position so it is easier to reach the brakes without being in a full road crouch.

The LeMond is steel, and basically handles bumps by being more flexible than the aluminum bike. Newer Alpe d'Huez models seem to be aluminum and carbon fiber; I have not tried them. This bike is not for trail riding! When I bought it I was accustomed to doing a lot of brute-force pedaling up hills, and this made things grind a lot because I tended to flex the frame from the force of my pedaling. I had to learn to spin and downshift a bit more, but it is a useful skill. You can only downshift so far; it only has two gears on the front. If I did a great deal of hill-climbing I might consider having a third, lower front gear put on.

When I was looking for a new bike for Isaac, I settled on a low-end Trek aluminum frame mountain bike that cost about as much as my Marin cost originally. However, I regret that choice a bit. While the frame seems to be OK, a lot of the other parts seem to be made of very cheap steel and have rusted out very quickly, even the cables. That's disappointing; I should probably have gone with a more expensive brand known more for quality than quantity and been willing to pay a bit more. We're paying more anyway; we just put some more money into Isaac's bike and replaced the seatpost clamp, which originally had a quick release that is always letting the seat slip down or rotate, the rusted cables, fixed a bent rear derailleur, and replaced his flat pedals with grippier pedals with toe cages.

The theory is that if you have flat pedals you can only transfer force when pushing straight down. If your pedals get wet or muddy or you are climbing, sometimes our feet will slip right off. So instead they make the pedals spikey (they have aluminum cleats that help them grip your shoes), and then there is a "toe cage" that wraps around your toe so you can push straight forward and pull up as well. This lets you use your hamstring to help power the pedals on the up-stroke and also contract your calves on the down-stroke without losing your pedals -- basically, you can use all your leg muscles, and get more efficiency from your pedaling. Isaac found this to be an immediate improvement.

He also got a more hard-core seat: a skinny seat that is mostly hard with pads where the "sit bones" go. Bicycle seats present a bit of a design paradox, like toilet seats. If they really gave you proper full support they would keep you from properly doing what it is you need to do! (You'd lose the ability to go to full extension with your legs). There was a Dilbert cartoon that summed this up by saying something like "problem: bicycle seats are hard. Solution: wear funny pants.") This seems to imply that the real solution would be to make the seats softer. That's not really a great solution, though, except in limited cases, as I'll explain.

Bike seats seem to have split into two camps. The idea is that if you are going for a slow, short ride, and you're not a jock, and your seat is lower so that you aren't actually using the full extension of your legs, padding is nice and keeps your rear end from getting sore by spreading the pressure around and distributing it widely.

This only goes so far, though. The problem is that some of your parts are not designed to handle sustained pressure! For a longer ride you actually want your weight to be supported primarily on your "sit bones" with a little padding under them, but you want the seat out of the way of your legs, so you can fully extend them. You don't want a lot of additional padding, which will pinch on nerves and arteries (if you're a man, it can cause sterility!) Also, when your legs are strong, you wind up carrying less of your weight on your seat, and you tend to stand up on the pedals occasionally to stretch things out, and so your seat is not such a big factor anymore. Yes, I do still get a bit sore on a rock-hard seat, even wearing bike shorts with a chamois pad in them... but less sore than on a soft seat, and I don't get tingling and numbness in my whole groin, which indicates I'm compromising blood flow down there, and doing (possibly permanent) damage.

I'm hoping to take Isaac on a road ride with me this weekend!

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