Tightened the bolts on the frame. On weekends I went to another city. When I went there, everything was fine. When I went back, again there was a high frequency vibration. On the handlebars, footpegs and even a tank. This is not an ordinary vibration from a big single, because I clearly feel the difference. When I press the clutch on the move and open the throttle, vibrations also appear. Maybe is something wrong with the engine?