1 1/8 is not a small cutting diameter, I would guess its normal. My thunderhead 100's have that. Getting that diameter with an extra blade sounds interesting, though I have never had issue with the theads, left a huge hold on the way in a 8pt in PA and busted right through the chest and into the ground, awesome bloodtrail, well for the 50 yds, then the skid marks he made crashing were easy to follow