I've learned, or rather reinforced, a valuable lesson the last two days: Complacency, and any sort of unusual noise or behavior from one's bicycle, must not be tolerated. I've already earned being called "anal" once for my meticulous brakepad and rim cleaning after riding through some mud, but in some situations one can't skimp:
1) derailleur stiction continued to make it difficult to shift into my smallest chainwheel in front. One cause of this was the bending and misalignment of the parallelogram of the derailleur, following its mangling on our first day, which caused it to jam as it skewed. However, I fixed that problem at mauricios by realigning the derailleur parallelogram pivots. But it still proved difficult to shift into the smallest chainwheel. Ultimately this proved to result from fatigue and bending of the cable where it had a sharp turn; I knew that was a problem but tolerated it to get underway. So, yesterday morning I carved a poplar wood derailleur hanger that attaches farther down on the downtube with a cable clamp, so the cable housing has a smooth path the whole way. Its not going to be a problem again.
2) On the first real hill in the wild, on honey springs road, Lydia passed me by standing up in the saddle and hauling... I thought, "Wow, she's strong and feeling her oats". But later on she started to lag, and just didn't seem too happy. A while later, maybe an hour into some serious climbing (perhaps 1500 feet?), she said something about the rear not shifting correctly, and I noticed she was in the smallest chainwheel in front, and the third from smallest in back, going up a steep hill with a 100 pound bike. I didn't want to be THAT guy, who always offers mechanical "advice", and she's pretty (very) competent herself, so I'd risk seeming insulting. We rode on...
Finally, she walked a hill, and I realized something was *really* up. It turned out she couldn't shift into any gear higher than her third smallest chainwheel in back! instantly I recognized her rear derailleur's cable clamp was loose, and so the cable slipped through it, and there wasn't enough travel for it to shift into the "easier" gears. She'd been going up mountains in what I'm guessing was 32:24 gearing! She'd not been able to see the rear casette with all the bags, and was taking personal responsibility for her inferior hillclimbing muscle, I think. Hardly! Stubborn, but also impressive. She should be invincible with the 32:36 gearing that I think is her low gear on the Surly "Long Haul Trucker" bike she rides. (Which by the way I think is an excellent bike and I'd consider for my next touring bike).
3) My chain started to not shift correctly. It'd seem to not quite want to stay smoothly in gear in back. Every second or third pedalstroke, it'd "hop", and when crawling up the hills this could be quite upsetting. I laid the bike on its side and shifted while looking close at everything, but the problem wasnt there anymore. Hm. I rode on. Then about a halfhour later, starting from a standstill and REALLY crunching on the pedals to get moving up a 7% grade (I and bike weigh perhaps 350 pounds): BANG! the chain ripped apart. It turns out the periodic skipping was because one chainlink was slightly misshapen, increasingly deforming on its way to complete failure. That link would catch as it happened to coincide with some feature on my rear cassette, and cause the skip. This was dependent on chain tension so I didn't see it when I did my unloaded shifting observation. Basically, It'd given me warning, and I ignored it, or satisfied myself with not finding the cause in a cursory inspection. Never again. If Lydia thought I was anal regarding bike maintenance before, I'm going to seem downright neurotic from here on out.
The chain was a brand new shimano $20 nine-speed chain from REI, but it has these newfangled barbone shaped link pins. They've got larger diameter collars that hold the chain links together, but if you need to shorten the chain, by pushing one of these out, the collar is sheared and its easier than on a normal chain for it to fall apart then. I've had this chain less than a week! I appreciate their good intentions in removing weight, but I'd like the fullsized chain link pins, please. I'll be super observant of any further shifting troubles until I get it replaced with a good, heavy, cylindrical-link-pin-held-together, chain...
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