this is exactly what i'd tell a customer in the shop.
Originally Posted by blackcannon
I took apart my Dura Ace st-7700 shifters to give them some cleaning but after putting them back together, I found the right shifter's small lever will not budge when I try to shift down...It stays stuck unless I hold the bigger lever in place...Any ideas besides buying new shifters???
you missed a screw, or did not assemble it properly. i've done the same thing, and that's actually a pretty common problem with taking those shifters apart.
there's a little plate that is there. right up at the top of the big lever, just to the right of where the small lever come out of the shifter body, you'll see a phillips screw that's holding the plate to the big lever, and up above that, inside the shifter body, the other half of the plate has a hole in it that stabilized yet another place that allows the two levers to move independently. to hold the big lever in place when you want to shift the small lever. if it's not installed properly, the big lever will move with the small lever. it's either that or something else got mucked up when you took it apart.
speaking as someone who's taken a few shifters apart, and disassembled an ultegra shifter as far as anyone can possibly disassemble it (it was already broken, i wanted to see what was in there, as did everyone else in the shop), it's complicated in there, and there's a reason why shimano doesn't want anyone taking it apart in the field. they are not meant to be field servicable, and do not need to be disassembled to clean and lubricate. if you need to lubricate, a shot or two of triflow lube usually does the trick.
shimano has a 3 year warranty on dura ace shifters. unfortunately, you've voided that warranty by taking it apart.