The Iso-Grips are much more comfortable than the stock grips. However, if you are planning on installing them on a Spyder ST you are in for some work. The left grip went very smooth, I removed the plastic housing then several wraps of electrical tape and it was finished. The throttle side required LOTS of work. The throttle return spring has a tendency to slip out when when you take the end cap off of the stock grip. It's a lot of fun getting it back in place. The throttle sleeve is well over 1 inch in diameter, which is the inside diameter of the throttle grip. After resorting to a lot of redneck engineering, lots of time and a few expletives it finally went on. Am I glad that I installed the grips definitely? Would I do it again probably not knowing what I know now? A possible alternative that might have made it easier would have been to order grips for 1 inch bars but then I am not sure of the inside diameter of those grips. Spyder ST folks proceed with caution!