On Wednesday, November 2, 2016 at 3:51:00 PM UTC-5, Sir Ridesalot wrote:
What Andrew is geting at is that there were a number of variants of Shimano 600 through the years.

From your first post I think you might have what's know as N600 (New 600) cranks and bottom bracket. Prior to that 600 was known as 600EX.

Are your cups and your spindle in good to very good condition? If so then it'd be a whole lot easier just to replace the bottom bracket bearings.

Some Shimano Dura Ace and 600 bottom bracket spindles have a different taper than most other brands. that's the issue Andrew is referring to when he talks about tapers andthe Campagnolo bottom bracket.

Dura Ace and 600 are two different groupsets. Dura Ace is Shimano's top of the line road bike groupset and 600 (now called Ultegra) is tnext one to Dura Ace.

If it were me and the bottom bracket cups and cones were in good condition i'd just replace the bearings and adjust the bottom bracket for smooth running rather than try to find a cartridge bottom bracket that will work. YMMV


Thank you for explaining, Sir Ridesalot. Now I think I have a handle on what Andrew (AMuzi) was saying.

I appreciate the further input, AMuzi and jbeattie. I will be grateful for my local bike shop and meanwhile, contemplate my own rebuild this winter, if only to ultimately learn exactly what my LBS is going to do. I like seeing the parts and how they go together. It's not urgent. Whenever I get the identifying numbers off the bottom bracket, I will try to remember to post back, for anyone else interested. I bought this bike in 1986, not 1987. I am a woman who happens to be very competent IMO at working on my old Honda Civic. Still I have not done any serious mechanical work on my bikes over the years. I appreciate the parts explanations here in particular.

Signing off