Hi All, New to the forum. I am a lineman by trade so I have an understanding of physics as it applies to not getting yourself killed when setting telephone poles and line tension. I am also a short track inline roller speed skater and they just announced that they will be allowing 125 mm wheels in certain events. Since these wheels are new, they carry a much larger price tag than the 110 mm wheels used now. Currently my set up is 4, 110 mm wheels per skate with a hardness of 89A. (standard urethane hardness guage). A 125 mm set up would be just 3, 125 mm wheels with a hardness of also 89A. My question is, what is the difference physics wise in roll, etc between the two in a percentage form? You can also get 100 mm setups (also 4 wheel). Is it as simple as you get around 10% more roll per push as the wheels are approx. 10% larger than each other? Do you gain even more counting friction when you go to a 3 wheel set up instead of 4? Thank you for your input.