In a magazine test in 2000 the Sabre ran 117mph which is about 106. Horsepower was dynoed at 54. You have done about all you can to gain performance without going inside the engine. Compression is very low at 8 to 1, the benefit is that is will run well on poor fuel. If you uped compression to 10.5:1, installed hotter (higher lift/longer duration) cams, you could see some healthy horsepower gains, but it is probably a lot more cost effective to buy a different bike with more horsepower. The Sabre is a wonderful bike, but has limitations that you probably need to live with.