Hi all... I got very strange case when I replaced my EU honda1000cbr 2014 stock exhaust by a universal pipe direct not S type and changed the muffler by universal one also.... My top speed not passing 289....i lost 10km and a lot of power and I don't know the reason..... Is it the back pressure effect.? Or o2 sensor is reading different flow in the exhaust that's why sending lean messages.?.... For information I returned back stock one and I got my top speed again.... But up to now I don't know what happened
