Hoping to receive some sage advice on an issue I'm having with my 1984 R100RS: I have about 800 miles on an extensive restoration, including having the heads done (valves, guides, springs, seats, Randy Long), New pistons (Wossner 9.5), new Bosch coils, complete Bing rebuild, new plugs, new fuel tank screens. The bike is sluggish. It starts immediately, idles well and accelerates smoothly, but feels pretty gutless. I have it jetted exactly the same as my 1984 R100CS, which has much better throttle response and noticeably better "grunt" when cracking the throttle open at 3k rpm. I have checked the timing and am able to see full advance at 3k rpm. I am positive the valves are adjusted correctly, and am very confident with my Bing rebuild and adjustment abilities. Of note, I did use aftermarket diaphragms, which I have heard mixed reviews on, and they do seem thicker than BMW oem. Could this be my issue? Has anyone here experienced similar diaphragm- related performance issues? Otherwise I am stumped.