Bicycle inner tubes are the most common item we sell at the shop, and I wind up spending at least a few minutes each day explaining the difference between Presta and Schraeder valves. I also explain how some deep-section aero rims require a long presta valve. Today a customer asked if there is any disadvantage to using the long valve tubes even if his bike didn't have deep rims. "No real problem. The valve weighs a few grams more but I often carry a long-valved tube as my spare even though my bike has non-aero rims. It comes in handy for Samaritan purposes."
"Samaritan purposes?" the customer asks.
"You know, you might not need it, but you might come across some other cyclist with a flat and he might need a long valve tube."
Sure enough, on the ride home tonight, as I roll across Mercer Island, I see another cyclist pulled over with a flat tire. I give the standard call out of the fellowship of the wheel, "You got what you need?"
"Actually, no," the guy replies, "I was so anxious to get out when the weather cleared that I left home without my spare tube or patch kit."
"No problem," I say, "here's a tube. Do you have what else you need?"
The fellow had a pump, but no tire levers and he confessed that he'd never changed a flat before.
"You're in luck," I say, "I'm the shop manager for Bike Works." I show the guy how to pry the tire off the rim and locate the cause of the flat. I inflate the tube just enough to give it shape, place it in the tire, fit the tire on the rim and inflate the tire. While I'm doing this, I get to know Matt from Medina. He's very grateful that I saved him from a long walk home. I tell him a little bit about Bike Works. Matt says he'll stop by my shop some time and send his friends there. He also insists on giving me $20 for my efforts on his behalf.
I'll use the money to refill my stock of Samaritan tubes.