Sunday, June 29, 2008

Don't trust my beater anymore

The old Super Course has been making a pinging noise I can't track down. Because everything moves when anything moves on a fixed gear, it's really hard to isolate components.

The frame is 30 years old. The fork came off my used Eisentraut, which I purchased in 1979. It was a replacement fork on a frame with a 1975 serial number, so it could have come from 1976. The frame was an early Limited that had been raced by person or persons unknown. I guess they crashed it and trashed the original fork. I don't know how long the frame set had hung in the basement of Belleview Bicycle in Alexandria before I came along.

In summation, the frame and fork are probably both 30 years old and have been in continuous use since 1979. The fork has been on at least three bikes I've built up. The Super Course frame actually left my hands and went to another rider or two before coming back to me. I built it into its present form in the early 1990s.

For at least the last couple of years I've inspected the frame for cracks at least twice a year. This week I may have found some. They're not the usual shape in the usual places, and they're very fine, so I can't be sure. But any doubt gnaws into your brain when you're spun out at 200 rpm in low gear, ripping down a steep decline too short to be worth flipping the wheel. For that matter, rumbling down a longer grade in the high gear at an easy 27-30 mph, you don't look forward to doing a tuck and roll as the fork disappears from under you.

The Traveler's Check doesn't fit the fixed gear beater niche. So now I have to come up with a ride as functional and fun as the Super Course with as little investment as the original. I paid something like $30 or $50 for the frame in 1979. I had all the other parts. I've bought tires, chains and a Shimano UN 52 bottom bracket for it. Everything else was handed down...oh yeah, except the two-sided hub in the current rear wheel. But that one replaced a freebie two-sider someone gave me minus its axle. Atom hubs are Atom hubs. I pulled an axle and cones out of some old Motobecane wheel to get that one going.

In 1979 I did not know how much frame proportions matter to ride comfort. Back then, if my 'nads cleared the top tube that was good enough. Now I know that the Super Course's long top tube agrees with me, and its ample tire and fender clearance make it easy to set up for foul weather. So the next beater must duplicate those qualities.

For now we'll see if one of two salvaged forks takes care of the noises, and monitor the possible cracks in the down tube. Only one frame in my pile of spares has similar tire and fender clearance, and it doesn't have the top tube length. Time to cruise the dumps and trash piles. The Universe will provide.

No comments: