Old 10-14-06, 11:50 AM
  #6  
San Rensho 
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Originally Posted by garth
The problem is that I damn well love this old bike. I bought it for $140 on Ebay 6 months ago. It had one messed up wheel, so I purchased another campy hub and I already had a matching rim in my possession. I built up the wheel with double butted spokes and had a beautiful rare set of Ambrosio 19 Aero wheels. The wheels are definitely faster than other wheelsets I have had plus they are light and unusually durable too and rare, did I mention rare? The brakes are rare Modolo dark anodized with Bianchi Celeste factory accents to match the Celeste bike. The seatpost is Campy Aero old style and the seat is Italian something or other with titanium rails and vintage to boot! The crank is Ofmega as is the headset. The bike fits me to a T and I'm faster on this thing than any of my other vintage bikes.

This morning I went out on my first long ride on this bike with a fast pack. Even though I was faster than usual, something inside told me to back off the wheel in front of me. Instinctively I didn't suck wheels like I usually do, but technically I couldn't detect any real obvious imbalance. I chalked it up to it's being a new bike that's not entirely tuned in .. you know how that takes time no matter how good you are at it ... seat angle, bar angle, seat height, limit stops etc.... It was a bit wet as it had rained the night before and we were moving at 25 or so for a slight reduction in pack speed. Up comes a speed bump that I've handled a gazzillion times before and when I hit it with my hips off the saddle, suddenly the rear wheel of the bike slid a couple of inches to one side (the left side .. the short seat stay side.) This has never happened to me before in the rain or otherwise. The speeds we hit are dangerous if everything is not absolutely tuned in. Everything has to be perfect. Even though the alignment isn't critically off, for my style of riding it's off enough I think. This time I didn't go down but what about the next time?

I have a frame guy who'll probably pop one seatstay off and rebraze it for about $50 but then I'll have to repaint. I could file the bottom of the left rear drop out and epoxy in a 1/8 inch piece of metal on the top of the dropout to compensate and then I guess it would be in alignment and you wouldn't really see it, but that would be such a hack job that I can't do that with a good conscience. What else can I do?
I would try to repeat the back end kicking out. Try going over the same bump and see if it happens again. Were you pedalling or doing a little bunny hop over the speed bump? If so, that is probably what caused the squiggle.

If the bike tracks fairly straight, I would just ride it, but if you are going to the next level, I would Dremel off 1/16 in. of metal on each dropout before I started in on tube repair.

I'm also a fan of double checking everything. "Measure twice, cut once" was a lesson that I learned the hard way, and not the first time. I would also double check that one stay is longer. Try this. Put the bike in a stand, shim the legs of the stand until the seat tube is vertical, measured with a spirit level. The put a rod in the drop-outs and check to see if the rod is perfectly level. If it is, then your problem is somewhere else.
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1980 3Rensho-- 1975 Raleigh Sprite 3spd
1990s Raleigh M20 MTB--2007 Windsor Hour (track)
1988 Ducati 750 F1
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