Hi Fellow owners,I have a Hreg ZZR 600 D,was a trial enthusiast,never thought I would ride a sports/tourer.I love this bike,however as it is getting on a bit I want to breath some new life into it,I am considering a new manifold,or exhaust complete,and some tuning,Really all I want to know is,what is the most suitable exhaust ,is it worth it,will it run better,are there any 600 D specific tuning guides or books,Any advice or comment gratefully received DsmCul@Aol.com