fast700c is correct, i was talking about the telescoping post models, not the isp models. if there is excess post inside the frame it can click or creak against the walls of the seattube with the forward-backward rocking of normal pedaling action. cutting off the excess about 1/2inch to 1 inch below the seat cluster junction solves this (and saves weight
). the frame itself needs no modification.
as for the bottom bracket clicking - it is true that most of the bb86 bikes i have worked have some type of extreme stress clicking, while a very few have a consistent creak. these creaks are usually solved by replacing the bottom bracket. installation is crucial with these, you must be much more careful than when installing a headset. while the hard aluminum cups of a headset will straighten themselves out a bit as you press them in, the plastic cups around the bb bearings will deform immediately as you press. they must be *perfectly* straight to begin with, or you will likely have some noise due to the cups not sitting perfectly in the frame. when they are lined up correctly, i have found there to be a minimum level of clicking. after each installation i have done with this level of care, no bike has developed anything other than a sprint or extreme load type ticking sound. perhaps this is just the design of the bb. in my mind, every bike will make some noise, and that this is simply the personality of the design. so long as the sound is nothing distracting, it is unimportant. however, many people cannot stand even the tiniest of noises from their machine. these people tend to spend a crazy amount of energy and money to eliminate them (and paying my salary in the process
). i just get on and ride. when my bike clicks, it means i'm riding hard.
re: removing and reinstalling the cups - i am passing along the information given to me by both my giant and my shimano rep. they feel it will not give an ideal installation to press used plastic cups into the bb. once they deform, you will never get as good of a full seal all the way around the cup. as a professional mechanic, i go by what these representatives tell me until my own experience proves otherwise. in this particular case, my experience has upheld their assertion. i have re-pressed the bearings upon customer request on two different occasions, and i could feel a difference pressing in the used cups. there was a bit less resistance, which leads me to believe that a second or third installation will never be the same as the first. that said, my re-pressings did improve creak levels, likely because i took so much care assuring that they were aligned properly.
long story short, with my own bike, i will use new cups every time i overhaul my bb. with your own bikes, feel free to re-press, but keep in mind that new cups will offer a much better chance of a clean, secure, and noiseless fit.