2009 GSX650F - Downshifting problem
My gearbox randomly stucks when downshifting from 5th to 4th and from 3rd to 2nd. It does it only after intensive and longer riding. When it's cold everything is OK Last night I did inspection for something loose in the gear shift change mechanism, but everything looks tight and neat. When we spin the rear tyre and try to change gear we spotted that the small lever with the bearing stays in the shown position and the shift drum gets stucked and needs some help to spin (chech the position on the attached photo).
The bike is only 1900 miles since 2009 and it last owner did only 80 miles last year with it. The last oil change was May 2016 and we noticed some corrosion on the metal plates on the clutch, which leads us to think that the bike was not driven regularly just as preventive maintenance. I'm thinking of couple of possible problems - issue with the shift drum shafts (corroded or poluted), issue with the shift forks (bent but I have no idea how you can bend this thing...), or something else really stupid, for which we have no clue...
Before taking out the engine and open the gearbox just want to make sure that we're not missing something. Any ideas? It makes the sticking problem very rare and usually it does it just once, but last weekend it really was bad after some aggressive riding it didn't want to go from 5th to 4th no matter what. I had to turn off the engine, put the bike on the stand for 10min and wait to cool dow a little bit, and than I managed to get into lower gear. But after few miles it started again sticking between 5th and 4th... This time with a little bit harder kick was going into 4th gear.