Put it on the close up setting!

Try backing away from it and using the zoom, don't use didgtal zooming though.

 

I am looking at my stock 3.4" Radix Pulley and the 2.9" Pulley that I have just received from Allen as well as the 2.75" Pulley that I am returning to him. I honestly can't tell the difference in the ribbing on the Pulleys... they are identical.
What strikes me the most is the weight difference. The stock Pulley must be twice as heavy as the ones Allen has supplied.