Join Date: Oct 2011
Location: New Bern, NC USA
Upgrade mufflers and jet carbs
One of the best and more affordable mods to add performance to your GL1200 is to replace the stock mufflers with Harley Sportster slip-on mufflers and jet the carbs up one size.
I had a GL1100 with this setup and the upgrade added more HP and more torque. There are 2-3 different Sportster slip-on designs (one design has crossover pipes - this will not work without custom piping).
The pipe OD is the same/similar to the Wing muffler OD.
Search this board and the web...this has been done many times. I love the difference in ride and sound, also. If you stick with stock Sporty mufflers, your bike will not be much louder until you romp on it. Your Harley friends will be impressed by the sound and response.