I have a an older steel Lemond with 600EX that I use in the park (ie crash) and rain etc. The right brake shifter wont catch to shift into the easier/lower gears. I figured its just worn out. Its a 7spd so I can't use any of the new 8, 9, 10 spd stuff. I don't want to change to those as it means new derailers, cassette, hub, etc. Is it serviceable, can I still get a 7 spd somewhere? should i just ride it and suffer on hills? Any ideas?