Sunday, June 27, 2010

Red Zone

The Toyota 3VZE V-6 of 1990 doesn't compare to a more contemporary powerplant. Its 3 liters promise a little over 140 horsepower, more comparable to a 2010 econobox than a pickup truck. That means on any sort of incline, the 3VZE has to spin fast to develop enough power to pull the Sunrader up hill. Climbing the Grapevine on Interstate 5 a few weeks ago, we were down into second gear to maintain 45-50 mph.

And I was watching the temperature gauge. High revs, heavy loads and slow speeds are all ingredients for overheating -- something that almost never happens anymore in modern automobiles. The little Toyota didn't disappoint, and while the needle moved substantially higher on the scale it never once approached the red zone. This after more than 100k miles of service. Chalk it up to reasonable care and maintenance by previous owners, and fresh coolant.

Today I took a bike ride in the mid-day heat. That is something I typically avoid, but after a late start and a tire change on the Serotta, it was after 11am when I set out. What had been predicted to be a day in the high 80s turned into more than 100 degrees F indicated on our back patio.

Last summer, on a similarly hot day, I got about 30 miles into a 40 mile ride. In spite of carrying extra water and being diligent about drinking, I hit the red zone and had to stop. Completely. It was the first and only time I've ever called home for a ride. And it took a few hours back at the house to actually recover.

Today, I used some human coolant called EFS, similar to Gatorade but with a better electrolyte content, at least for me. I had good legs, which is surprising considering my lack of training this season, but remembering last summer I was cautious through the entire ride. In spite of my legs feeling good, any time I upped my effort on a climb or a strong acceleration I almost immediately overheated.

And the signs were obvious.

Normal human response to heat is, obviously, to sweat. And for body hair to lay flat -- at least according to the small amount of research I did online after my ride. Today on the road as my core temperature climbed, so did the hairs on my arms. Straight up. Kinda like that temperature gauge going into the red zone. And I got the chills.

Now apparently that little signal is the beginning of the skin's evaporative cooling system starting to shut down. The human equivalent of steam slipping out from under the hood.

This year I knew enough to pull over and find some shade, drink, and add coolant. It was definitely a day in the red zone. But I made it, so I have that going for me which is nice. Now to work on the horsepower. Or at least the power to weight ratio.

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