Just bought a kawasaki 600 {2000} rode it and realized there was no water and no oil,,now is smoking really bad from exhaust.never had a bike before therefore no idea where to go from here..

if you want to know the bike is getting enough oil it must produce white smoke via exhaust ,most of these 1974 bike do not have knob for oil adjustment but you adjust manually by adjusting the oil cable

If gasoline is left sitting for a while (2-3 months) it attracts water, which could cause the "smoke" and rough running engine.
Unless it is a 2 stroke engine, no oil should be coming out the exhaust. Hold a clean rag or a bunch of paper towels at the exhaust opening BE CAREFUL NOT TO BURN YOURSELF and than check if, whatever the rag or paper towels catch is oily. If it is a 4 stroke engine, and oil is the exhaust fumes, a seal inside the engine is gone and has to be replaced.

sounds like a blown head gasket.take it to a repaire shop and have it pressure tested.

Continuous or just for the 5-10 seconds.
If continuous you may have oil seeping past your pistons oil rings or valve guides oil seals.
Check your spark plug see if they are fouled badly (covered heavily and oily) or just covered by oil and sooth lightly.
If 5-10 sec it is normal as the engine is heating up there are normally a little oil seeping past the seals.

Jack, find a newer bike. Most dealers will not work on a bike over ten years old. Parts availability is one reason. Another is the workload in the shop and the need for the mechanics to stay current with the new models coming out yearly. If they fixed every bike that came in the service backlog would be really bad.

The KLX 300 was never a popular bike. Not many still arround. I would not buy the bike until I rode it for an hour or so. You gotta check the suspension, handling, power, shifting smoothly, shocks, forks, power valve, clutch, water pump, oil pump, radiator, electrical system, front and rear brakes, carb, rings,

garbage oil, maybe it wouldn't hurt to have the valves checked and adjusted. black smoke means oil is getting past the rings or the valves more than its supposed to be. clean the plugs often too.

The shifting problem is a bent shift fork. It will only get worse and is expensive to fix. The smoke is probably getting past a exhaust pipe gasket. When you fix the shifting it would be a good time to rebuild the top end with new pistons and rings.

Its most likely your rings. They get worn and start letting oil into the combustion chamber. They aren't extremely hard to replace.

Check the seal behind your water impeller there are o rings back there if one of them goes bad you will leak antifreeze into oil, your impeller is run by the oil pump i believe, you should not see oil in the water also your bike will run fine but when hot will foul the plug with water look for white smoke sometimes and the smell of anti freeze on start up
i have a 400 4x4 doing the same thing new piston rings and top end now lossing water but runs great oil looks real thin
took to the dealer to fix this week will let you know how i make out.

if it is using oil, then u got stuck rings, which keep running the bike and keep a eye on the oil, or you need the top end rebuilt.