Yamaha 40cv 2 stroke 3 cyl 2006: rpm and alternator output frequency

sandro · #1 September 12th, 2008, 10:16 AM

Hi,
I need to calibrate a tachometer which has a potentiometer to adjust the rpm scale, so I thought to use a frequency meter connected in parallel to it...
but which is the correspondence between RPM and Hz?
Thanks a lot.

Silvertip · #2 September 12th, 2008, 10:32 AM

6Hz/Rev

sandro · #3 September 13th, 2008, 04:33 AM

Do you mean: 1 crankshaft revolution in 1 second = 60 rev in 1 minute = 60 RPM = (60x6) 360 Hz

so...
at minimum 700 RPM = 4200 Hz
2000 RPM = 12000 Hz
5500 RPM = 33000 Hz

???