Is there a general rule to calculate MPG on a motor or a place I can go to get the info? Reason I'm asking is I will be headed to Guntersville to fish a tourney. I have a 17ft tin deep v with a 90hp carburated 2 stroke, with a 19 gallon fuel tank. Top speed under ideal conditions with 2 guys all our gear, full tank and livewell is around 40mph. Gas guage works at will. Want to know how far I can run.

Thanks

I don't know but i'll show you where to gas on the water if you get in fuel trouble

If you keep it back to 2/3's throttle I would think you could get about 4.5 - 5 mpg. If you run WOT, I would guess about 2.5 - 3 mpg.

Understand though, I haven't run a small motor in many, many years, and other than my jon's, have never used a tin boat, so this is totally a guestimation on my part.

If it was a four stroke or DFI motor, it would be a lot more, but carb motors generaly don't give you great economy. Hopefully someone with your motor and similar boat can give you better numbers

Is there a general rule to calculate MPG on a motor or a place I can go to get the info? Reason I'm asking is I will be headed to Guntersville to fish a tourney. I have a 17ft tin deep v with a 90hp carburated 2 stroke, with a 19 gallon fuel tank. Top speed under ideal conditions with 2 guys all our gear, full tank and livewell is around 40mph. Gas guage works at will. Want to know how far I can run.

Thanks

Rule of thumb is 10% of HP at WOT. so you 90HP should use about 9 gallons of fuel an hour at WOT. Therefore, consuming 9 gallons an hour going 40 miles an hour you are getting about 4.44 miles per gallon. You can go about 84 miles WOT. you mileage will increase greatly at slower speeds. Say under 4500 rpms.

Rule of thumb is 10% of HP at WOT. so you 90HP should use about 9 gallons of fuel an hour at WOT. Therefore, consuming 9 gallons an hour going 40 miles an hour you are getting about 4.44 miles per gallon. You can go about 84 miles WOT. you mileage will increase greatly at slower speeds. Say under 4500 rpms.

This is a good rule of thumb, nice post TD, you also have to take in the weight factor as well here, while not so much on plane but getting on plane will consume more fuel as well as, water, wind conditions etc... will also play a role, I would figure closer to 3 or 31/2 miles per gallon.

Regardless I would carry an extra 5 gallon can.

Good luck by the way and be safe !!!

Thanks. I posted on a few different forums and 4+ is about what everyone said.