Yamaha F50/F60 difference.

**Mark Poole ModVP** · 01-13-2023, 03:08 PM

Okay, question for the Yammy techs. I watched a youtube vid of a guy that takes the air intake apart on his F50. Inside of the single round intake hole is a disk that is nothing but a air restrictor that decreases the opening. He removed it and said there was a noticeable difference in the performance. Could this be the only difference between a 50 and a 60? Also, would the map sensor on the fuel injection automatically adjust for any difference in the airflow?

**espen** · 01-18-2023, 01:41 AM

Would like to know too for the carb version, there is a 70hpnas well. Is it the camshaft ?

**CharlieN** · 01-22-2023, 09:36 AM

If I am correct, the 70 has a bit more compression, different ports and cam as well as throttle being a touch different. Basically the head is different.
I had the specs on the carb motors but not on this computer, although I think all the service manuals are on here if a rummage deeper into them.

**slowJEEP** · 02-02-2023, 11:36 AM

The yamaha 50 and 60's are real similar to the Mercury 4 cylinder 40/50/60 with a two valve head. As in, you can bolt the Yamaha head to the Mercury block. The 70 Yamaha departs from the other two by having a 4 valve head. Picture is of a merc 40-60 head next to a yamaha 70 head