I have an old training bike running 8 speed shimano 105 components. The left hand STI lever is knackered and is getting increasingly hard to downshift. Am having a hard time finding a 105 8 speed lever with which to replace it (made harder by the fact that it’s a triple - embarrassing I know but I picked the bike up cheaply in Switzerland and was doing a lot of mountain rides over there at the time so it seemed like a good idea…).
Question is - will any old Shimano triple shifter do the job? Can I put a 9 or 10 speed 105 shifter on there? Or a Sora or Tiagra shifter? I think the answer is yes but I’m passing the bike on to a friend who wants to do his first triathlon this summer and I don’t want to give him something that doesn’t work.