In the medical drama "House," caustic genius Dr. Gregory House diagnosed mysterious afflictions that suddenly struck down the patient of the week, for eight seasons of often nauseating entertainment. The nasty genius used his mega mind, extensive education, and long experience to slice through the confusion and bring us the answer.
After the previous medical drama ER made patient -- and even doctor -- survival far less likely, viewers were trained not expect a happy ending. House delivered pretty often, but sometimes the patient died. Also, House would be wrong several times in the episode before delivering the right diagnosis within a few minutes of the end. After you watch a few, you realize that early certainties never pan out. "Do this!" House snaps at his team. We look at the clock and go, "Nah, that ain't it."
Without all of the good-looking actors, life and death stakes, and medical bills that would bankrupt a medium sized city, bike repair has become like episode after episode of House. A patient comes in with weird symptoms or what looks like a simple problem at first. We diagnose and treat. It fails. We try something else. Thing is, no one has bike medical insurance, so we the greasy healers are the ones who stand to lose a lot of money on these false starts.
Bike shops have no medical associations in which we share our experiences and publish papers in a journal. We don't know what other mechanics are doing. Online videos show either idealized versions of various procedures or selected experiences of individuals who may be amateurs and inexperienced. And if the video doesn't cover the exact model in the exact year that you're dealing with, the information might not help at all. On top of that, who has time to spend hours trolling through search results in hope of finding a tutorial that might not even be out there.
Forums may yield some useful knowledge, but are just as likely to attract experienced misinformation or loud, confident, and wrong newbies. You have to sift carefully to find cases that fit what's in front of you on your work stand.
The manufacturers really don't care if you can fix anything. They just want you to buy it. Ancestral sources like Sutherland's and Sheldon Brown can't keep up. We're thrown back on our experience and education -- such as it may be -- to analyze the problem.
With every added cog in the cassette, mechanical shifting gets more and more temperamental. As the manufacturers abandon what used to be the state of the art, replacement parts for that number of speeds are made more cheaply. This includes shifters and derailleurs. You had fancy ten-speed when it was the best? You're just part of the rabble now. Eleven speed is rapidly going the same way.
Any repair could turn into a frustrating mystery these days. I like a challenge, but most of this crap is just an affront. Parts are disappearing for the old, reliable, simple bikes, while tech support barely exists for the new, throwaway bikes. I get it: to a racer, the entire bike is as consumable as chains, tires, and tubes used to be. As long ago as the 1980s, racing was already turning into a massive science experiment. It has only gotten more so. Rider and machine need a complex support system to eke out those hundredths of a second per kilometer.
Advancements in racing technology through the 1970s improved quality for all riders, because we all used similar mechanisms, shaped slightly differently for variations like racing versus touring, and, later mountain biking. As disciplines diverged, particularly off-road, there was a lot less cross-pollination.
People here used to complain from time to time about the level of detail I would go into, but less time was wasted diving right in as opposed to dithering around trying to figure out how to avoid it. Lately, though, it seems that diving in doesn't assure solid results. Too many things have to work too perfectly together.
The road bike that's giving me fits right now was built on a bare frame in 2017. The owner rides hard. He raced a couple of short seasons, mostly just a nearby training series, but it's a competitive series. He rides with people who never go easy. Over the years, we have replaced gear cables and housings as necessary to restore precise shifting, along with chains and cassettes. This time, though, I can't get it to behave.
The brifter seemed to be worn out. It needed too much lever travel to engage, which meant that it didn't have enough left to climb to the low gear cog. I changed the brifter. It was crisper, but still did not have the reach. The chain gauged pretty new. We'd already changed all cables and housings with tried and true 5mm. The bottom bracket cable guide can't be removed because the bolt that threads into an insert in the BB is rusted in, and the insert itself is broken loose from the bottom bracket shell. It's been that way for years. It shouldn't matter as long as the guide stays in position. Cable tension should hold it.
I rigged a brifter in parallel, using full-length housing, to test the derailleur itself. It shifts the full range. So something in the cable system is eating lever travel. I can see motion where the cable housing enters the upper end of the downtube. There's a bit more waggle where the housing exits the chainstay near the derailleur. Is that enough to cause the problem? Parts are all original, and very simple. But the hole in the downtube could be worn. After all this, is the answer something simultaneously stupid and difficult?
I tried every combination of cable housing, including 4mm, 5mm, and mixing widths in case the flex characteristics of the 4mm handled the bends better than the 5mm we can get now. I'm happy to say that 4mm did nothing to help. Eventually, I put on a new brifter, new cassette, and the 5mm housing we had installed first when we thought it would be the routine repair we had completed successfully several times over the bike's life. I got it to hit every gear from the 39, and every gear but the Ned -- the full cross 53-28 -- from the big ring.
Given the option of taking the bike with the gears we could get or making permanent modifications to install full-length housing, the rider opted to take the bike as it is. He even said that it hadn't been getting the Ned for a while, and he was fine with that. We'll see how things go.
Nothing is a sure cure anymore. Every fix is temporary. Who needs another metaphor for life when we just want reliable machinery? I hop on my primitive bike, day after day, and just go. I can change a cable on the side of the road in about 15 leisurely minutes. If I get a flat, I put in a new inner tube, pump it up, and ride on.
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