I got mine from BellaCorse.com but you can also get them from Brent's site, NewSpeedmaster.com. Both have 16-19 available. I've learned a lot since my initial posting of this thread. I'm surprised, from what I've learned, that more people don't consider changing the REAR sprocket. The very next thing I plan to try is leaving the 18T on front and changing the rear to 43T. The rear tooth make less of a dramatic change than the front. 18/43 would be about half way between where I am now (18/42) and stock. I'm waiting until after my Daytona trip. I just wanted a little higher 5th, the change will accomplish what I need and get low gears a little closer to stock. This combo is stock on the 865 Thruxton and T100 and would be what 865 SMs and Bonnie's would have if they change their front to 18T.
