cut the vent line from the fuel tank
to the carbon canister. Maybe stick an airhead fuel filter in there to keep rocks out of the tank.
Only the US gets the poorly engineered cc, everyone else gets a "vent line".
Most anything will corrupt the cc, water from it's vent line, raw wet fuel from an over full tank.
Only in places with detail emission inspections will this be a problem, and it will make it easier to export your bike to Peru.
Mine has been fine for 50k miles with one airhead filter, sometimes it has some presure in hot weather, it never draws a vacuum anymore.
"Gravity, sometimes it works better than I want it to" -- Land