Hi, had the 172 a couple of weeks after running an STI for a year and I must say Im over the moon with the little pocket rocket. However I have noticed when the rev counter hits 4000rpm there seems to be a vibration noise from the centre box of the exhaust. Once past 4500rpm it goes as away. I was wondering if anyone else has had this propblem with their 172 and what causes it and whats the cure?
Cheers in advance