Hello everybody,my cbr125 has a weird rattling/klocking noise. I dont know what causes that sound.You can hear it only on idle.Here is a video of sound: . I appreciate your help.

 

It sounds like an exhaust leak.

 

When was the last time it was fully serviced, including valve clearances mate ?

 

Hi,valve clearances are good,some experienced guys said to me,that the piston is making the sound,ill open up the engine in the next week and we'l see the thruth,however,im still waiting for your opinions guys,thanks.