... but thanks to my extremely cautious (some would say
overly cautious) technique, I'm here tonight in one piece, able to tell you about what happened.
Just past the summit on the freeway outside Carson City where I stopped to take this picture of myself, the highway descends into the valley below. For nearly a mile and a half, the road drops at a fairly steady 5% to 6% grade on long, sweeping curves with picture-perfect pavement and impeccably wide shoulders. In other words, this is where a lot of cyclists love to let it all hang out. While the 65 mph speed limit is probably unattainable on a bicycle, I suspect that breaking 50 mph wouldn't be that difficult at all. More power to those of you who can do it safely and enjoy it.
But that's not me. Perhaps I've just seen too many bad things -- or perhaps I'm just a klutz -- but I take my descents much more carefully. On a typical AIDS/LifeCycle ride, my top speed is usually only about 31-32 mph, and on training rides I usually have a slower maximum speed. And when I'm on a road that I've never bicycled before, I'm even more cautious. In fact, if I'm at all unsure about a descent, I'll unclip my right foot before starting down. My goal is always to have a Plan B available if need be. This time, I needed.
At about the halfway mark down the hill, I was feathering my brakes and keeping my speed somewhere between 20 and 25 mph. Then I heard the extremely loud noise from behind me ... followed by rattling and all sorts of noises I couldn't decipher in about the half-second of reaction time I had available to me. My first reaction was that a major component on my bicycle had failed dramatically. But the first order of business was stopping. Because I had one foot already not attached to the bike, I saved a precious fraction of a second. I was starting to slow down, but I didn't want to look back or down to see if I could identify the problem quite yet. All I knew was that the sound was very scary, and I was wasting precious thinking time on the possibility of being stranded out here on the freeway without a working bike.
Had my tire failed again? The temperature was somewhere north of 90 degrees, and my new bicycle has seemed more prone to tire failure (which I've documented here several times) than my old one. A destroyed tire, while not a ruined bike, would still leave me with few immediate options.
I finally came to a stop, quite some distance down the hill -- far enough that I didn't want to walk back up the hill against high-speed traffic to see if there was any sign of what happened. Sure enough, my tire was flat. Amazingly, though, a quick check of the tire itself didn't reveal any of the tell-tale rips and tears that I've previously had. What about the other mystery noises? Again, a cursory visual inspection didn't reveal any damage, and the chain (which was new just two days before) was still in position.
Adrenaline in overdrive, I decided that the best immediate course of action was to get off the freeway -- and out of the blazing sun -- as soon as possible. I walked the remaining 0.4 mile or so to the bottom of the hill and the beginning of roadside development, where across a sandy field I found a partially disused strip mall with a shaded service area in the rear, secluded from any prying eyes or direct sunlight. After I removed the rear wheel and tire, I checked the tube, and there was only a tiny puncture in it (it wasn't ripped wide open as I had suspected it would be) -- and nothing was lodged in the tire at all.
To make a long story short (well, it's really too late for that already, isn't it), I replaced the tube, reinstalled the tire, and found that everything on the bike appeared to be OK. I continued with the remaining 35 miles of my 62-mile ride without incident.
But my takeaway from this episode is that I'm more satisfied than ever with how I descend. Had I been going at the 40-45 mph that pretty much any cyclist can achieve on that hill, I strongly suspect that I would not have been able to stop without catastrophe. Again, if you have the skills and experience -- and desire -- to descend faster, you have my respect.
But please, if you don't ... do not feel pressured by other cyclists to ever descend faster than you're comfortable descending. A 1-mile hill at 20 mph takes 180 seconds to descend. At 40 mph, the same hill takes 90 seconds. For me, the bottom of the hill is still there, waiting for me when I arrive 90 seconds later. And I'm OK with that.
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San Mateo County has been lacking a current bicycle map for quite some time. But that's been rectified, and despite what you might have read on a certain bicycle-related mailing list, PDFs of the map are available online.