Hi, I run 15/39 gearing for topspeed but am after more power. It only just pulls it and if I back off in top I have to drop it a gear and rev the rings out of it to change back up. I have an FMF Fatty pipe and and run a 175 main jet. The engine has just been rebuilt but unfortunately before I read about the piston cutout mod. Ignition timing standard. I have boyeesen reeds. In Australia I seem to run into a brick wall when I ask about performance mods for the KX5. People think your mad and that they have plenty stock. I am desperate for more top end as my mates ride KTM990 rallys and the latest Berg 570's. Looking for simple to wild mods that can be done. Any help appreciated.
