Saturday, April 3, 2010

Spring maintenance and upgrades

The weather is lovely outside and tomorrow we'll be going on the first FLCC Sunday Ride of the year. Today (and a good deal of yesterday), however, I did a lot of work on Wolfgang. I installed a new granny gear, a new front derailleur, I checked and repacked the rear hub bearings; switched from Ritchey Cross Tires to the Conti Gatorskin slicks; and I wired my accomplice's BUMM Toplight Line Plus rear light.

Switching from double to triple clearly was the most laborious process and actually I wasn't able to complete it successfully. I had bought a Shimano XT FD-M773 front derailleur, a Salsa 26t chainring and a 118mm bottom bracket to adjust the chainline. Using the fabulous Park Tool instructions, the cranks came off, the bottom bracket was removed (required several attempts and a bunch of WD40), threads cleaned and regreased, and the new bottom bracket installed.

As I had to take off the chain anyway and the current chain had reached the .75 mark, I also switched the chain back to the old chain. What I immediately noticed was the difference in corrosion between the two. The old one was an Sram PC 971, the more current one to be switched out a PC 951. Despite mostly fenderless use during the 2008/2009 winter, the 971 was completely corrosion free; whereas the last winter had left significant traces on the 951. The difference between the two chains is just a couple of dollars--and the fact that the 971 is nickel-plated. I'll definitely keep this in mind when buying another chain.

Finally, I put on the third chainring and the new derailleur and started adjusting. This is where the trouble began. I couldn't get the derailleur to clear the small chainring, even when the L limit screw was set to the max. I initially thought I had done something wrong, maybe with the height adjustment. But after extensive consultation with my online friends, I've come to the conclusion that derailleur and bottom bracket just don't go together, even though the specifications and Glenn's expertise implied otherwise. What I'll try next is to re-install the old Tiagra derailleur and see if it's going to work -- apparently double front derailleurs often also work for triple.

Odo Wolfgang 3954 km
Odo Gunnar 1048 km

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