I'm thinking you'll prefer 54mm soon. Hooray 288XP!
52-54mm-ish range (most of my saws in this range are SAE rather than metric) probably is my favorite. Covers my 5-5.3ci class saws. 82cc Macs and Homelites. 87cc Mac S-250. 85cc Poulans. 81-87cc Huskys. 72cc 272XP.
56-58mm-ish brings us the Husky 1100-2101 series, the 394-395XP, the 6.8-7ci Homelites, and the 6.3-7.5ci Macs.