Re: 1985 90 HP Inline 6 - Jet Size
Don't down size jets, you'll burn up pistons... Use the jet listed for your altitude. Best way to achieve the best possible economy is to have the engine in proper tune, have a prop that allows the engine to spin at the top end of max recommended WOT revs and use fresh fuel and a good quality oil....
Main jet -- 0.074 (sealevel to 2,500 ft) Standard jet fitted at factory.
Main jet -- 0.072 (2,500 ft to 5,000 ft)
Main jet -- 0.070 (5,000 ft to 7,500 ft)
Main jet -- 0.068 (7,500 ft and above)
Bowl vent jet -- 0.098
Chris..........