I drove to the dealer and back this morning about 60km/40 miles to have my handle bar warmers installed and the temp. was -8C/18 F. The cat bypass without any baffles was loud especially when downshifting, WOT or blipping the throttle like the guys working on the bike got a kick out of. At steady RPM of 3500 the sound was much quieter and tolerable. Start working on the bypass next spring.