Reply To: Jetting a GT125R – 2017 ..?
I already had filled a handfull holes in the “dB-killer” with pop-rivets (just shy of half the total holes). Not much difference. I guess the muffler is sized for much larger engines.
BTW, if jetting is right, NO (4-stroke-) engine will ever make more power with restriction in the exhaust-system.
Part-throttle/mid-range can change, due to cam-overlap.
90/92,5 was on the lean side with stock muffler (lightly modified) and BlackWidow pipes. On MY bike…(with the mods earlier mentioned).
I do not like running AirFuelRatio in 15+numbers at high rpm-wide open throttle…most engines likes AFR round 13 for best power,-also to control temperatures.
Old and grumpy,(?), have fairly wide engine & tuning experience, "restoring/resto-mod" on cars & mc, worked as electronic tech. (retired).
GT125R - sold. New (used): 2012-GT250R-efi (sold)+ 2017-GV-125C (sold) - got my old 2018-GT-125R back... 🙂