I have a 1974 900 Z1A. I raced mine at a local 1/4 mile drag strip in 1975 best of 3 runs was 11.35 I don´t remember the speed, just the time. I did do a run on a long straight road one day and had it up to 135 mph, when shifted to 5 th it wouldn´t go any more so back to 4 th and 135. At that time I weight about 170 lbs. I still have the bike and started restoring it to ready for summer 2008. O, yes I bored it out to 1140 CC that summer, w/ kerker header and larger main carb jets & Electronic ing in 1975.