proper RPM for honda 75

dougnsandy · Posted: Sun Apr 09, 2006 9:23 pm Post subject: proper RPM for honda 75

My 22 c dory does about 3500rpms full throttle. the gps says around 23kts, does this seem normal. The honda manual says the motor should redline between 5 to 6k?

Sawdust · Posted: Sun Apr 09, 2006 9:27 pm Post subject:

Not normal! What prop are you using?

Dusty

Salty Dog · Posted: Sun Apr 09, 2006 9:27 pm Post subject:

Not normal for that. I had a similar thing happen on mine. On the back of the tachometer, there's a 4 position setting knob, I believe labeled either 0-3 or 1-4 (I forget without looking). Anyway, find out what the setting should be for your motor year and size (call your Honda dealer and ask them), then check to be sure the arrow is pointing to the right number. Mine was set up wrong, and as soon as I fixed it, RPM readings started showing correctly.

Jack

rogerbum · Posted: Sun Apr 09, 2006 9:44 pm Post subject:

Salty Dog's explanation sounds likely to be correct. 23kts wide open on a 22CD with 75 horses sounds close to the correct speed. I get a max of 26-27kts wide open with my twin Honda 40's when I'm light and the water is flat. I got about 23kts today with full fuel, three guys and plenty of tackle, food supplies etc. However, I was running at between 5000 and 5500 RPM. My guess is that your tach is not reading properly if you're going 23kts.

dougnsandy · Posted: Sun Apr 09, 2006 10:11 pm Post subject: RPM ?

I will look at the back of the tach and see if it is wired correctly. I have an aftermarket generic prop with no markings. I am not sure on what prop to use, I go long distances often with just two poeple on board and light gear. Any suggestions on prop size?

Salty Dog · Posted: Sun Apr 09, 2006 10:19 pm Post subject:

The factory tests that were done on the 22 Cruiser with the Honda 75 used a 13 3/4" x 15" 3-blade aluminum prop. That's what I use on my setup, which is the same as yours (2001 Cruiser with Honda 75). By the way, your speed is probably right on, when my tach was misreading, my speed was accurate, the tach was just saying I was doing that speed at a lower RPM, that's why I'm pretty certain the set position for the tach is just incorrect. My tach too read around 3,000 to 3,500 RPM at WOT when it was set to the wrong number on the back. I don't remember the correct number for mine (it's not here to look at, but I believe mine was off by 2 numbers, was at a 4 and should have been a 2 or was at 3 and should have been a 1 or something like that), but a dealer should be able to tell you which number that arrow should be pointing at. I think that will solve your RPM readings then.

Jack

oldgrowth · Posted: Mon Apr 10, 2006 2:30 am Post subject: