maybe a stick
This depends:Diesel engine cold start, engine wear, damaged or worn injection systemGasoline engines display blue smoke from oil usage:If a puff of blue smoke on cold start, valve guides are leaking slightlyA puff of blue smoke after a deceleration with no throttle applied, valve guides are worse than he above example and oil usage may be starting to be an issue due to this.Blue smoke at idle and most times when the engine is at low throttle or medium throttle settings. This engine is badly worn or has been badly overheated damaging the piston ring sealCloud of blue smoke at high RPM high throttle settings. This engine has "Ring Flutter" and will require new pistons and rings to correct.
failure of head gasket :)
the high pressure oil pump
a belt slipping
check spark plugs,wires,cap,rotor, and or coils.
A dirty spark plug can cause your lawn tractor engine to run at high RPM. A bad fuel filter can also cause this.
its either engine vibration,high rpm,black smoke!
You have worn valve seals and posibly bad valve guides.
An idle set too high can cause a 1994 Nissan Pathfinder to run at a high RPM in 5th gear. A bad transmission gasket can also cause this.
5000 rpm is extremely high unless you are drag racing in which case the engine is built to handle it and will be rebuilt often. otherwise white smoke usually means oil smoke, so you are pushing oil out somewhere. high rpm also means high oil pressure, how is your crankcase ventilation ,pcv valve, no ventilation will cause extra high pressure in the engine and oil could be weeping out of your oil pan gasket valve cover gaskets or engine seals.
Running slow with high rpm is a sign of slippage. If the vehicle is a straight drive then the clutch is not grabbing and is slipping, if its an automatic then the transmission is slipping internally.
A bad spark plug or spark plug wire can cause your Kawasaki engine to miss at high rpm's. A dirty fuel filter can also cause the engine to miss.