fb24f4f@v0nsild I figured that is why the roller bar was just a bit to small, so good call on that.
I had to sand down on the outside of the arm up front, and along the outside of the teeth. It was very very VERY minimal, maybe a thousandths of an inch. I wouldn't change a thing. Personally would rather have to sand as no 2 hop up units are going to be 100% the same. Its almost as if I just had to take off the outer coating on the material, not sure what alloy you used so that's just speculation.
fb24f4f 100% Recommend. Couple areas needed light sanding, and the hole for the roller pin to go through is to small, easily fixable with the right tools (didn't use a drill bit, but rather a small bit for my dremel to sand the inside of the hole)
I paired this with the decepticon bucking, and first impressions blew my mind. Straight as an arrow.