Tuesday, March 02, 2021

Follow the bouncing temperature

 March came in like a nasty day in April, but immediately shifted to a harsh hit of January. The forecast as of Sunday afternoon showed the temperature dipping to a single-digit night on Monday, a frigid Tuesday, but then daytime highs well above freezing on the ensuing days, alternating with hard freezes at night. That has now shifted to a single bounce to the upper 30s on Wednesday, followed by a solid few days at or below freezing before the next wave of sustained thawing, but it still shows vestiges of the volatility that has become common.

With cross-country ski season in the immediate vicinity apparently tapering off, bike repairs have already stacked up. We've had three of them hanging around from the end of last season, held up by unavailable parts, and then suspended while the workshop shifted to things that don't mix well with grease. Then five more piled in, for people who are traveling south in the next couple of weeks.

Trainee Dave and I have been missing our bikes. He said that he wished it was bike season, so I set him onto what seemed like straightforward tuneups on a family fleet of four, preparing for a trip to Florida. The first one he picked was a Specialized Chisel 29er in a large frame size that looked like it might fit him. Go for the fun one first. He gave it minor cleaning, but it wasn't even very dirty.

A clean bike can be very bad news. Is it clean because it's had light use, or is it clean because it's been hosed? Based on chain wear, we both thought that this bike looked lightly used. Everything seemed pretty straight. The brake pads weren't very worn... Then Dave tried to run it through the gears.

Mountain biking has embraced the 1X concept because front derailleurs and ham fists don't mix. Riders who might have unbelievable finesse when airborne and rotating in balletic maneuvers off a jump put nowhere near the same delicacy into coaxing a chain between rings on a crankset. Road riders are similarly afflicted; front shifts are the biggest contributors to chain failure.

The chain takes abuse shifting up or down. Going up, the rider mashes the lever and forces the chain over against the side of the larger chainring, hoping that the specially engineered pins and ramps do their thing and slurp the chain over without hesitation. That might happen half the time. The rest of the time, a certain amount of chewing takes place. Going the other way, the return spring of the front derailleur gets its one chance when the shifter releases cable tension abruptly. The derailleur cage snaps over, hopefully dislodging the chain from the larger ring and depositing it onto the smaller one. It's like having someone direct you right or left by punching you in the face. If the chain goes out over the high side or drops to the inside, a rider can sometimes ride it back onto the chainrings by shifting the opposite way and continuing to pedal. If that maneuver doesn't work, it graunches the chain even more. We still try it.

With a single ring, front derailleur problems vanish completely. However, you now have to provide the whole gear range with the rear cassette. This led to low gear cogs of 36, then 40, then 42, and now 50 teeth. The rear derailleurs have had to evolve longer and longer cages to handle the chain, and still try to manage a reasonable gap between the upper pulley and the cogs on everything from an 11 (or the even more ridiculous 10) up to the 40, 42, or 50.

All the wide range systems that I have worked on have obvious trouble managing this range, particularly getting onto and off of that huge low gear. The bike that Dave was working on had a basic SRAM SX derailleur. We have no idea if it ever worked any better than  it does now, because the owner dropped it off with the usual statement, "It has no real problems, I just want to get it tuned up." He said the same thing about all the bikes, including one kid's 20-inch that was missing the axle nut on one side of the front wheel.

SRAM has spawned at least two different "B-gap adjustment tools" that are supposed to help a mechanic set the angle of the parallelogram to achieve optimal clearance between the upper pulley and the immense cog. However, this derailleur does not want to shift away from that gear once you're in it, no matter what the B-gap is. You take the cable completely off and shove it over there by hand and it settles in like it wants to live there forever, a tree-climbing single-speed.

Hosing could have led to corrosion and silt in the pivots. This would resist the return spring starting the derailleur back toward its released position. Under full cable tension, the parallelogram is folded quite tightly. If little detents had developed from wear, when it's all folded up it might stick. Clearly something is making it stick. I just have to figure out what. But right now, with ski season still nominally underway, it's hard to concentrate on all the variables of temperamental machinery.

I had one bike on my stand for several weeks. First we were waiting for parts. Then ski season got busy again after a lull while we had no snow. I was so far out of the flow of the repair that I couldn't say for sure that I had addressed all of its unique needs. The rider is not abusive, but he's relentless, and has already ridden three bikes into the ground. Indeed, when they dropped this one off the rider's father said, "Let us know if it's time to buy a new one again." And it's only been a couple of years, but between this rider's perpetual motion, and the industry's embrace of disposability, it's not ridiculous to consider having to replace your mid-price bike every two or three years. Well it is ridiculous, but it's become plausible enough to be accepted. I was going to say acceptable, but it should never be -- or have been -- acceptable. But a consumer public well trained by the ephemeral quality of everything else that they fork out good coin for is not surprised when their bike is made to the same exploitive standard.

With this foretaste of the mind-numbing and soul-destroying realities of servicing modern bikes, we both agreed that what we missed was riding our bikes. As much as commuting stresses me because I have to do my daily miles in what passes for rush hour, I have reached the point in driving season where I've turned into a complete asshole behind the wheel. I always hit a peak some time in February and shock myself into mellowing out a bit until I can get the hell out of the car and return to the more satisfying flow of biking.

In February I have to get to work earlier to rack the rental boots that had to sit out overnight to dry, and perhaps take the bandages off of elderly rental skis that I had to glue after the previous day because the bases were starting to delaminate. All of this has to be completed before opening the doors to the day's flood of renters, who will keep us in continuous motion until late afternoon. We're masked, they're masked, we're trying to keep everyone somewhat separated, and the whole slam dance usually obliterates a lunch break. Sometimes it ends with more OT doing service work like mounting bindings or waxing skis, that we couldn't do while immediate demands from the rental and sales counters called for all hands on deck. It no longer energizes me the way it did a couple of decades ago. Now it's just something to get through.

If the day isn't busy, it drags, because we can't get too deep into anything else in case it does get busy. Even if we know it's going to be quiet, because we're getting rain or something, converting the main workshop to bike work involves moving a lot of stuff that doesn't get along with grease, and cleaning the bench completely before moving it back again for the next wave of seasonally appropriate business.

If we had a bike-only shop, I would solicit winter overhauls and custom builds. But even those are less fun now that traditional skills have less value. It's only a rare old codger who wants me to build a set of wheels. I used to like the alternative activities. I still believe in using the season for what it offers, rather than fighting it. It's still reasonable to look forward -- as much as I look forward to anything these days -- to the more consistent rhythm of riding season, now that I can no longer count on a consistent rhythm of winter activities.

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