Hey guy's I got a set of JHA ( i think they are) chambers with the MC21 bike. My question= the left side pipe has a ''threaded-port'' welded on , ( looks factory done) , with a plug. "Pyrometer-tap " I suspect? anyone know? as well as , Why only one side? and not the other? Oh , and the ''port'' is directly straight up and right at mid-chamber., ( fattest-part) of pipe. Also Does anyone have an original set of the matching JHA silencers for sale ,for said pipes? Be kinda cool to get the old originals, is all. thanks ;dave