Hello, a buddy has a Yamaha DT 125, in which the piston rings are broken before about 7 tkm, whereupon he bought and installed a new piston. The cylinder did not take any damage during the break. The power is also quite normal and the car always starts at the first kick, but it clatters like the sow. You can hear it in the video. Strange is that it has been clattering since 7 tkm and the noise hasn’t changed a bit. What can that be? The sound is dependent on the clutch pull or insert gear. it always claps when the engine is running, i.e. also when the clutch is pulled and the gear is inserted. here is the link to the video:http://www.youtube.com/watch?feature=player_embedded&v=OvX7lysK3t8 Who has an idea?