i ordered a new pair of shifters (dura ace SL-BS77) to replace my wobble semi-broken ones on my bike... my question is, if the shifting system is working well and i just wanted to replace the shifters because they weren't staying attached properly to the bar-end (ie rotating around with tension, falling out during a ride from road vibration, etc) do i have to do any retuning or tightening, or just take the cable out and replace the new shifters??
also any advice on installing these would be great
Since you're going to have to pull the cables out anyway, it's a great time to replace them if they've been in use awhile. You're going to have to adjust cable tension, obviously, because you have to pull the cables out. The limit screws on the derailleurs should be fine. Remember that once you get the shifters positioned in the ends of the bars, you loosen the bolt (turn counter-clockwise) to secure the shifters. Those are very nice shifters, I have some myself. Good luck with them-
I have Shimano indexed bar-ends on two of my bikes and I often mess up by installing the boss cover (it goes between the body and the lever) in the wrong orientation. I quickly discover this, though, since I don't get all 8 clicks and take the lever back off and rotate the boss cover. I think the Shimano instructions say to point the tab of the boss cover down but this assumes drop bar installation (mine are on aero bars). Basically, it needs to point the same way the lever does when in top gear but I can never seem to remember that.