I got curious about backweighting one time, so I ordered a bunch of those Tourlock weights and all the tools to install them. I experimented with all ranges of shafts, steel and graphite, lightweight and heavy. I closely monitored swing speed, feel, and where I was hitting on the face. Most irons I could get away with 20-30 grams of backweight and still have good control and still feel where the clubhead was on the backswing. I actually picked up a couple mph to boot. The most interesting iron was the Wishon 870 with Recoil shaft, a real lightweight at 71 grams. This was a 7-iron that I was consistently swinging in the 68-72 mph range unweighted. I kept adding backweight til I was swinging in the low 90’s, and even hit 96 mph when I got after it. But I had little control. I had ball marks high and low, heel and toe. 70 grams of backweight didn’t work, lol. I could no longer feel where the clubhead was during the backswing. I tried it later with some of my woods with mixed results, still have 30 grams in my Wishon driver, but it’s so forgiving it doesn’t seem to hurt. If I were you, I’d just get a various assortment of screws that will fit inside your shafts, along with some face tape, and go to the range and experiment. Focus on how tight those face hits are after each change, and make sure you can still feel the clubhead on the backswing. It usually take a bunch of weight to lose the feel of it, so you’re probably safe. One thing I have noticed-adding a substantial amount of backweight will lower ballflight. Substantial weight will vary on each person, depends on how strong you are, and your swing speeds, I’m guessing. That 30 grams in my Wishon driver brought my ballflight down, as it did in my Juggernaut driver.
