I just bought a new 107” M8 and part of the deal was a Stage 1 with slips of my choice, (chose Rineharts 4”).
After the fact and 500 miles later, I phoned the company and asked about the baffle size out of curiosity, (previous bikes and friends bikes have all made over 120 square with 2”). They said it’s 2.5”. Ugh.
I’m impressed with the huge roll on power compared to my other Harley’s but since it’s my first 107” (and have nothing to compare to with other M8’s), did I shoot myself in the foot with these huge baffles?
P.S. Stock header with cat.

Your M8 has a higher stock compression ratio than the twinkies. Mine came with the 2.25” baffles and was told there’s no desernable difference between mine, and the performance baffles, which are 2.5”. I have fantastic low end grunt, so you should be fine. Rinehart knows what they’re doing.