Shimano 105 left shifter is hard to shift?
I just started servicing my own bike recently, but i'm pretty good with a set of tools and so far have been able to take care of most maintenance issues.
I'm having a problem where the left shifter is hard to shift, if I loosen the derailleur cable from the FD, it's a bit easier but still requires quite a bit of force to push the lever/button used to upshift into a smaller front ring. It actually always shifts into the correct gear, it just requires a bit more force than other 105 shifters i've tried.
Is it a problem with the shifter, is there something I can do to adjust the force required, or something internal on the shifter that needs to be lubed?
I'd really appreciate any ideas.