transmission problem

Hi everyone I have a 1999 Honda CBR f4 with approximately 68.000 km on original engine and transmission. I bought it last year mid July from a middle aged man with family. Month later I replaced the oil with Motul E-Tech 10W40 as the old oil seemed dark. Being new to the bike I tried to shift...

I have a 98 CBR 919 and currently having problems with the transmission. I know I have a worn out 2nd gear because when I give it gas in 2nd gear it bumps it back to neutral. Now the other problem that I'm having is that when I shift gears for example shifting up, the pedal stays upward and...