“In fact on the pre-EFI (carburetted) Bonnevilles, Triumph had to graft on secondary air injection in order to meet pollution regulations.”
Seems to be a popular mod to do the “airboxectomy” and remove it or at least remove the rubber intake snorkel on the air filter lid. I think one county in Arizona is the only place in the country to actually require Motorcycle Emissions Testing and I am not even sure that is still true. California I think had testing at one time and dropped it?
I haven’t done anything with mine, I have heard pros and cons and not sure it is the best idea for the type of riding I mostly do.. but thats another topic from this