Tuesday, July 9, 2013

Bow waves

The effect didn't videotape very well;
it's actually kind of dark in there.
This plastic sheeting (at left) is giving me an interesting lesson in wind resistance. There’s a remodeling project going on here at work, and the facilities folks kindly put this sheeting up to keep the dust and debris levels down.

When I walk down the hallway, the plastic starts billowing outward — at first, just a half-inch or so right alongside. But as you proceed (at a fairly brisk pace, as I tend to do), the air-compression wave gets stronger and moves ahead of me as far as 15-20 feet. It’s a classic “bow wave” (think of the wave moving ahead of the bow of a boat). 

Yes, if I had to compare my normal bicycling speed to
a watercraft of some sort, it would be this one.
Obviously this is taking place in the relatively confined space of the hallway; still, this has given me a new appreciation for just how much air we’re pushing aside as we ride along on a bicycle and why it gets more and more difficult to maintain a steady pace the faster you go.

I’m compressing and pushing a fairly significant air column out of my way just walking at 3-5 mph.  Imagine what’s happening at 15 or 20 mph, let alone a Tour de France pace.

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Thursday, July 4, 2013

Independence Day Ride

Went for a long-ish trek this morning on the Joliet Bicycle Club’s Fourth of July ride. The plan was to meet some members of The Chainlink and go for a moderate-to-slow ride for 30 miles, after which I was hoping to group up with one or two members of the group to extend the ride along the 45-mile route.

The selfie, taken while riding through the only
100 feet of shade on the entire route.
Well, the crowd at the start/finish point, Plainfield South High School, was large enough to foil the plan of just wandering around and looking for people who looked like they were wandering around looking for people. At about 7:30, I got antsy and decided to get on the road.

The route was very well marked, and the cue sheet was easy to follow. Unlike, say, the North Shore Century, where you’re turning every quarter-mile, today’s route went through the ramrod-straight roads north and west of Plainfield. Turns were sometimes seven miles apart.

Since I was riding solo, I had planned to do the 45-mile route, but on a southbound stretch, into the 5-10 mph breeze, I started to flag. The guy who had been drafting me for a couple of miles went around. Yeesh, I thought. Only 10 miles in and I’m about to throw a lung. Pelotons of sleek young jerseyed bodies flashed past me. I’m getting old and fat and tired, I thought. I should sell this bike and buy a rocking chair.

The course turned back north, downwind. With the decreased wind noise, I heard a faint scraping sound. I thought maybe I had picked up a leaf or small stick, which had lodged in the brake assembly and was rubbing on the tire. I stopped, examined both wheels.

(Must have been five people slowed or stopped to ask if I needed help. My fellow bicyclists are great people.)

I picked up the back end, spun the back wheel. It immediately stopped. Crap, I thought, the wheel’s
Met a guy in the parking lot who had
realized my two-wheel dream: a
bike rack on his motorcycle.
bent. But a little experimentation revealed that the brakes were the culprit: they had been about half-locked for who-knows-how-many miles.

I felt a huge sense of relief. It wasn’t me, it was the damn bike.

Well, I thought, all I have to do is disable the back brake and I’m on my way. Just have to be careful, and fix it when I get home. A close examination revealed a teardrop-shaped bit of plastic on the caliper. I played with it, and the brakes released. Huh.

Long story short: that little bit of plastic (I think) allows you to adjust the brakes to compensate as the shoes wear down. Somehow, I had hit that bit in such a way to tighten it about halfway -- maybe when I wrestled the bike out of the back of my SUV. When I hit that upwind stretch, the added resistance started to really make itself felt.

Shadowfax cockpit, somewhere north of Plainfield, Ill.
Well crap. I got back into the cockpit and -- with the resistance gone -- relatively rocketed the next five miles to the rest stop in Platteville.

But I was pretty sure at that point I wasn't going to make 45 miles. The extra work had taken a lot out of me. I sighed, ate a wonderful plum from the abundant food on the table, went back for another, and got back on the road.

By the time I got back to the high school (despite the last loooooong uphill mile on Caton Farm Road), I was actually feeling pretty good. I considered maybe heading back out for a quick 10, decided to save it for Saturday.

Total was 32.34 miles at an average speed of 13.88 mph. Not bad for a 52-year-old with a Frankenstein knee and the parking brake engaged. I think I’m ready for 50 miles, maybe a metric, and looking forward to my annual North Shore Century ride.

- 30 -

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