Bicycle Mechanics - Bottom Bracket replacement (Cup and Cone)

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bluesref
01-20-04, 09:31 AM
OK so my old bike that I use on a trainer has bad Bottm Bracket. The bike is an OLD ('80) Lotus Eclair road bike with Shimano Deore/600/SunTour 12 speed (2x6). Cranks are Shimano 600 square.

The bike has been OK negelected and the bottm bracket is CLUNKING. If I get this thing open and find a real mess I'm looking at replacement.

It's my indoor trainer 15-20 miles/day but its been ridden many many miles.

The questions are
1) can I replace this with a sealed unit like a Shimino UN53
2) is the conversion as simple as dropping in the new unit and keeping everything else.
3) OK I figure ~$80 at a shop and maybe I could do it for half that with pin spanners, crank puller and the unit.

Is there anthing I'm missing.

Thanks


demoncyclist
01-20-04, 09:50 AM
As long as you can find a new artridge bb with the right spindle length and threading, you should be good to go. As far as doing it yourself, you will also need a splined tool to install the new one.

tommy2pants
01-20-04, 09:56 AM
As long as you can find a new artridge bb with the right spindle length and threading, you should be good to go. As far as doing it yourself, you will also need a splined tool to install the new one.Threading is english. If you can't exactly match the spindle length,it usually is not critical, if you stay within a few mm.Pay attention to how much chainring to chainstay clearance you have and avoid going too short.Many old BB used nut type spindles rather than bolt type.Measure both types end of taper to end of taper.