Originally Posted by
dicktill
The bad news about the drivetrain is that in the top four cogs, the rear cassette/derailleur was either auto-shifting, or skipping, or something. I tried all sorts of trimming (front as well as rear) but to no avail. It felt as though it was trying to downshift, i.e., catching on the edge of the next larger cog, moving up "the wall" for a second, and then slipping back, but it could have been something else. Anyway, highly annoying. I'll have to check the chain and see if that is "stretched", and perhaps causing this "skipping".
In addition to the suggestions about chain, freewheel, and derailleur hangers, you may also want to take apart the rear derailleur cage and clean and lube the cogs. They may also need to be replaced if the teeth are really worn.
Originally Posted by
dicktill
The problem with using it wasn't the shifting, but rather the front end shimmy that I got going down hills. Have to recheck the front axle and head to see if there is excessive looseness, but it didn't seem that way.
If the axle and headset aren't the problem, it might be the tires. Do you have the same tires and tubes on the bike that came with it? Old, dry tires that have been sitting in one position for years? The tire casing may be deformed and you only notice extra vibration at higher speeds. I have a Centurion with a wobble that went away after replacing the tires.
Looks like you've ended up with the best of possible outcomes - you have a neat old bike you can ride and enjoy right now, and you have an easy upgrade path with lots of options.
You had asked for opinion about possible upgrades - did you buy this bike to look at it, ride it a few times a year on a nice Sunday afternoon, or put lots of miles on it?
If you want to spend several days a week in the saddle, I'd carefully take the old parts off, and replace the levers, wheels, cranks, derailleurs, and brakes. Then you have a sweet riding steel frame with comfortable geometry, and shifting/braking that is pleasant to use. Another bonus is MUCH greater parts availability and serviceability - like if you are on an extended vacation, trip over your bike, and crunch the rear derailleur. Much easier getting a new rear derailleur to match current parts, rather than 40 year old parts.
I'm in the process of doing an upgrade on my Trek 310, with Shimano 105, as time and money permit.
One request - please do not put a wheelset with deep v-section aero rims and fewer than 32 spokes on that bike. It would just look goofy.
