Anybody else hear a clattering sound at low speeds? I have about 300 miles on the bike. Checked oil level, thats ok, changed it 3 times since new.It almost sounds like bad gas detonation, but it happens with any gas.It also sounds like the valves are about to fall out. However the noise goes away when the revs get higher and there does not seem to be any loss of power. The manual recomends an octane rating of 95. Most of the premium pump gas around here is 93. Anyone using octane booster? Other than that, this is the most awesome bike I've ever owned. Blows my CR500 away. Is this normal?