I am sure I have seen a thread about this somewhere on the forum, but cannot find it. So apologies if repeating some stuff. My Raven Sports Tour has done about 1,000 miles and the chain has a pronounced droop. Should I start taking up the slack with the bottom bracket, leave it, or replace the chain. Will the rear cog and front chainwheel have worn to any extent yet, that replacing the chain will mean having to turn the cog and chainwheel around to offer a new surface to the chain? Do worn cogs manifest themselve in the same way as deraillieurs- ie the chain jumping off the teeth?