First thing is to drain the gas tank.remove and pour in a full can of seafoam.seal all openings and slosh it around.dump it out and if it looks really dirty repeat the process.next is to pull the carb,disassemble and soak it in some seafoam also.reassemble using new quality parts.check the air filter and if the paper seems brittle replace it.replace every rubber hose on the bike including all fuel and vacuum lines.even though the tires still have plenty of tread you should replace them.the rubber will have gotten hard and the sidewalls im sure are starting to crack.if they have tubes replace those too.drain the oil and replace the oil filter.the spark plugs should be ok but if you want you can replace those too.put in fresh gas and start it up.ride the bike for about 50 miles and change the oil and filter again.also at this time you should change the primary chain oil.if the cables feel sticky they may need a shot of graphite.you should be good to go.have fun.oh and get yourself a factory service manual
