I hear you Chuck. This goes to show that the tensioner can do its job, even w/ slightly different belt lengths. I don't know the difference in length between the 1145 and the 1153 that I have, but even with adding the 100mm tensioner pulley to my NW's PSK to take up some slack for the 62mm SC pulley as well as adding LM21's slightly larger alternator pulley, I have a real tight fit. The tensioner slot gauge is slightly to the left of center(about 1/3 or so), and will be closer to center as the brand new belt stretches a bit. It is my understanding that the 1/2 way mark is the sweet spot for the tensioner. Somebody please correct me if that is not the case. EDIT: I just checked the packaging of my gates belt #KO81153, and it is 116 1/4" OC (overall circumference).