The oddest thing happened on my Sunday ride. I was about six or eight miles from the end, when suddenly, I couldn’t shift from the big ring down to the small ring.
This was problematical, because at the time, I was approaching the crest of a hill, and I needed the easier effort the small ring would give me to get over the top. I back pedaled — something I never do — and downshifted the rear cogset. That did the trick, and I was in the small ring again.
But the same thing happened throughout the rest of the ride, until for the last two miles, I kept the thing in the small chainring, even when I had an inviting downward grade.
The next afternoon, I took the bike over to our club mechanic’s house. (It’s nice to have a “club mechanic” — in this case, a member with over 20 year experience “making money off of fixing bikes” who at one time was wrench for a pro team.)
“So, won’t shift down to the small ring, huh?” he asked.
His next question startled me.
I did a double take.
“Yeah, I am,” I replied. “Does that have something to do with it?”
He got the bike up on the stand and checked it over.
“I’m already seeing some corrosion on the brakes,” he said. “And here on the front derailleur, too.”
“That’s really strange,” I said. “It was shifting fine, and then suddenly, I couldn’t get it to shift down.”
“It was the straw that broke the camel’s back,” he retorted. “You thought it was shifting just fine, but it probably wasn’t. You’d just gotten used to it.”
There might be something to that. I’ve had some balky shifts in recent weeks. But I thought that was my lack of shifting technique, not my sweat. I watched him as he took out a bottle of lube and went to work.
“Front derailleur, front brakes, bottom bracket, rear brakes, in that order,” he lectured. “That’s what’s most affected by sweating. The rear derailleur rarely, if ever.”
He squirted some lube on the brake pivots.
“Pay attention to the pivots,” he said.
He shot some lube into the brake grip pivots, then pulled loose the brake and shifter cables and applied a light coat of grease to them. Then he cranked the pedals and started shifting through the gears — snick, snick, snick. Now it was time for the moment of truth — he changed hands to shift the front derailleur.
Click, click, it went. He shifted between the large and small rings several times. Each time, the shift was smoother than the previous.
“I think that’s got it,” he said, wiping his hands on a clean rag.
“So the trick is to keep everything clean,” I observed.
“I recommend that everyone at the very least wipe down their bikes at the end of the ride.”
I paid him for his trouble (he charges a pittance, compared to the LBS), loaded the bike into the car, and headed home.
This morning when I got home from my ride, I found a clean towel and went over the bike.
I routinely clean the bike after longer rides. If I’m feeling generous I clean my wife’s. Mine rarely has shifting or brake problems. Her’s often does. Coincidence?
I have a similar problem and have had to replace both shifter cables and a brake cable on my mountain bike. the sweat was hitting the top tube and then running down onto the exposed sections of the cables and eventually gumming up the housing. Just Sunday I watched with horror as a drop of sweat landed on my headset and promptly disappeared down into it.. great, just what I need, another time bomb to worry about.