Frank,
No real secrets. PMFR forks, wheels, sprockets. Very light headlight brackets, bolts ends cut to just clear nuts. Titanium rear axle, aluminum front axle. Here's a secret: if you run a KZ head, the early Z1 cam cover is half a pound lighter than the later KZ 1000 cover. The complete front end is PMFR. I weighed the original stock front end, handlebars and all, it was 63 lbs. The PMFR complete front end weighs 28 lbs. The handlebars are thin wall stainless steel, lighter than aluminum.