Originally Posted by verktyg

The weld in question looks REALLY cobby. It appears to have been done with electo-arc "stick" welding rather than more sophisticated TIG (Tungsten Inert Gas) welding. Most welded bike frames are assembled with TIG welding.

As @dddd mentioned, it's easy for the lower meting temperature brass to contaminate the steel weld. My welding instructors would have beat me soundly about the head and shoulders with a bundle of welding rods if I ever did a weld like the one on this BB...

That said, the kludged repair may last longer than the rest of the bike... On the other hand, why did it crack in the first place? Overheating during the initial brazing is the usual culprit. Or... it could have been a defective BB shell to start off with.

Now that I've offended everyone with my OCD aesthetics...


The only spec that I could find for a late 80's early 90's Chorus BB length is 111mm. I'm running Campy 111mm wide Veloce sealed bearing BBs with Chorus cranks on a number of bikes. They're inexpensive and so far have worked well.

They come with British (68mm wide) or Italian (70mm wide) threads with steel cups and a solid axle, steel cups with a hollow axle and aluminum cups with a hollow axle.

Note 1: Once a crank arm has been installed on a BB spindle and used, the aluminum deforms and all of the crap about ISO, JIS and so on is just that! If it fits, IT WORKS!

Note 2: The Brits call lugless brazed frames "bronze welded".... The US and the UK, two peoples divided by a common language!

verktyg

Chas.