I decided to fit the silencer from my Shadow onto my Rapide as an experiment in breathing as well as power. The result...
The Rapide with Shadow silencer ( a Toga absorption type) shows a much better roll on throttle response than with the spiral baffle. Rolling on 3rd gear gets to 70 mph much cleaner and quicker. However, on the roll off down a hill I get some serious backfire with (what I am told) a decent flame out of the pipe. Not quite so bad on the flats. Obviously I need to re-calibrate the carbs BUT in which direction? Advice please. Currently using 276 with 170 main jet and needle in 2nd notch. 7.3:1 compression and cams somewhere about standard. Ignition set at 34º.
The Rapide with Shadow silencer ( a Toga absorption type) shows a much better roll on throttle response than with the spiral baffle. Rolling on 3rd gear gets to 70 mph much cleaner and quicker. However, on the roll off down a hill I get some serious backfire with (what I am told) a decent flame out of the pipe. Not quite so bad on the flats. Obviously I need to re-calibrate the carbs BUT in which direction? Advice please. Currently using 276 with 170 main jet and needle in 2nd notch. 7.3:1 compression and cams somewhere about standard. Ignition set at 34º.