In second gear when i am riding my z250 i hear this type of hissing sound on the left side inside the case. Its only in second gear. Also when riding down hills with my rear brakes locked I sometimes hear a type or knocking sound. can somebody please help me out here. Thanks

 

I ride my friend 2004 suzuki and he heard the same thing he looked and their was a twig in his drive shaft

 

As it turns out it was a small twig.Guess i just never noticed it before. . LMAO. I just checked it tonite. I can't believe myself lol.

 

THAT happened to me too LOL, im glad u found the solution quick