Funny thing happened after buying some graphite shafts for Irons, Matrix Studio 84’s. One set of shafts sold as Regular, the butt label is showing “R” at CPM 279, while the other set sold as Stiff with the label showing “S” with a CPM 279. Does not the CPM dictate the “stiffness” of the shaft? So what gives…?
We did shaft profile testing on the Studio 84 iron shafts. We tested 2 each of the R, Firm and S flex shafts. They were 40″ raw length shafts. For the butt frequencies we test with a 200 gram tip weight and the clamp is 5″ wide. On the R flexes we got 335 cpm’s, on the Firm flexes 338 cpm’s and on the S flexes one was 342 and the other 344 cpm’s. With a lot of graphite shafts we see a 10 cpm difference between the flexes so the change between the R and S flexes is pretty close to normal from what we saw. Without having the shaft to be able to test them to make sure they were both 279 and even check them for stiffness at other points than just from the butt end it is hard to say what might be the issue with these shafts. From what we saw in our testing it certainly looks like something is wrong with these shafts.