As I've been tuning my '09 1125CR with upgraded exhaust and K&N filter (I've got the AFVs to within 0.5% front and rear), the engine now runs smoothly all the way down to 2000 RPM. While I never go WOT at that low an RPM, the engine makes quite the racket at lower RPMs - mainly below 3000 RPM. Is this normal? It runs smooth and has torque, but it sounds like there's a fair bit of chain slap going on and being new to the Rotax engine I'm unsure whether that's a sign that I need to adjust the valves, replace the chain tensioner guides, or WHY.