Flat fixr

October 19, 2020 § 10 Comments

Today we decided to test the backpacks on the longer but more gentle gradient of Mandeville Canyon Road. I had left the tent and tarp out overnight and they got soaked with fog/dew, so I left them in the yard and rode with a lighter pack, about 35 lbs.

In the meantime we’ve been doing some reading and pseudo research on the physics/physiology of packs, trying to answer a couple of questions, such as: Why would the bike go faster if the weight is on your back rather than on your bike? Because it clearly does.

One answer is in this formula, which I don’t understand because math, but which is also explained in English, which I understand better than math, in other words, some level of comprehension > zero.

I think this means that, all other things being equal, the thing that gets going the easiest goes fastest. In other words, it’s easier to move a 10-lb. bike with a 290-lb. rider than it is to move a 150-lb. bike with a 150-lb. rider.

The physiological aspect is a well-studied one, as people have been carrying heavy loads on their backs for thousands of years. This picture illustrates why a milkmaid doesn’t carry the pails up around her shoulders.

It also expresses another important formula that has held true throughout history: Mother-in-law + shitload of hard work = daughter-in-law carrying the shit x mother-in-law’s supervision.

These pictures show how heavy weights are distributed when people have to carry exceptionally heavy gear over long distances and rough terrain doing strenuous work. The photo where the firefighters are bent over with heavy packs looks similar to the position you’re in when bending over the handlebars.

On the way to Mandeville Canyon Road we saw a guy standing on San Vicente holding up an empty CO2 cartridge and yelling “Do you have a spare cartridge?”

The cyclists in front of us ignored him, but I stopped. “I got one. How long you been here, man?”

“Half an hour at least.”

“And no one stopped?”

“No.”

I shook my head. He must have hollered at a hundred people in half an hour; this street is the weekend freeway for bicyclists. “Here’s the cartridge,” I said.

But he didn’t take it. “Thanks. The one I have didn’t really work.”

“Oh. How come?”

“I don’t know. I’ve never used one before.”

I looked at his brand new Ultegra disc BMC, shiny, and the tires that had perfect tread. “Have you changed the tube?”

“No. I don’t know …”

“Know what?” He looked at the ground. “Was there air in the tire when you left home?” I asked.

He brightened. “Yep!”

“And how long ago was that?”

“An hour.”

“And then did the tire not have air in it after a while?”

“Yep!”

“Then you probably have a flat.”

“Yeah,” he agreed, after some thought. “But I don’t have any tire stuff.”

“We do.” I pulled out a tire and lever and he looked at it in horror. That’s when it clicked. He had no idea how to change the tire and hadn’t brought a spare and levers because, useless. But it didn’t explain the fact that he had a CO2 cartridge that he didn’t know how to use. “So how come you brought the CO2?

“I figured maybe if I ever got a flat I could just air it up.”

“Well you can, I guess. Briefly, anyway. This your first flat?”

“Yeah.”

“Let me change it for you.”

“Okay!” It was Christmas plus birthday plus bar mitzvah all in one.

I removed the through axle and pushed down on the derailleur to remove the wheel. Too late … my hand was covered in four pounds of blackest chain grease. I got the tire changed and he was, shall we say, grateful. “Can I pay you for all this?”

“Oh, thanks. I couldn’t take a penny less than $300.”

He smiled a bit nervously. “I really appreciate the help.”

“No worries,” I said, desperately trying to remove the grease with some magnolia leaves, which kind of worked.

The entire morning we’d been badassed by every manner of cyclist, but my newfound inner peace and tired legs from the day before allowed me to take the high road and not chase anyone. So I wasn’t surprised when I heard another set of carbon wheels overtaking us on Mandeville. But these wheels slowed …

“Hey, Seth!”

It was Attila, my erstwhile pal from Big Orange. He slowed to a crawl and started talking with us, but his crawl soon had me panting. We got to the top and descended. All the way home he kept it at a lazy and comfortable 17mph, which is to say that with my 35-lb. pack and dead legs I was fucking pinned. But I pretended to be fine. We got to Redondo and Attila, who after 60 miles still hadn’t gotten in a workout, continued on. “I’m gonna do a quick lap around the hill! Good seeing you guys!”

Then he dialed it up to his normal tempo pace and vanished in a puff of smoke.

We got back and checked our speed. Total elapsed average was 13 mph, faster than I went any single day in almost three months with panniers. The day before, with lots of climbing and chasing, we’d averaged 14, almost double my pannier speed on climbing days.

My shoulders were tired as hell even with the low-slung pack, and the suspender buttons on my pants as well as the pocket buttons on my jersey had bored painful holes into my back. Mental note: Take those bastards off.

END

Where Am I?

You are currently browsing entries tagged with backpacks and cycling at Cycling in the South Bay.