Now the sqweeeeking sound is gone and the shifting is smooth again. I don't know about other, but I sweat a lot. The bottom bracket was quite dirty and crusty. Even though modern bottom brackets are sealed, it's still a good idea to clean it out yearly. The little bits of dirt, sand, sweat and oil will build up. The same with the derailers. Last year I washed and cleaned the giant once a month. If a ride was wet and dirty, I tried to wash the bike within a few days.
One thing I need to do is adjust the tension on my dolce. My son rides it now and the shifters are too hard for him. I tried to look on shimao's website, but the pdf manuals don't show how to adjust the tension. I'm not sure if it's even possible to make it easier to shift.
