The kickstart shaft seal on my Yamaha YB100 started to leak. Didn't want to pull the sidecover off to change it so did it the 'cheats way'. Old seal in place. Using a battery drill I screwed in two plasterboard tek screws. This gives you something to grab with pliers to pull the old seal out. Old seal out and the tensioning spring had been dislodged, so that is possibly why it leaked. Don't have to go too far through the seal, just enough for the screws to grab. New seal in place.
