Max RPMS

[drag4striper]

The fellow I bought my used boat from with (a Yamaha 115 four stroke)on it said, not to go over 6000 rpm. Others have told me 5500 rpm.

I have just read that the newer four strokes have a rev limiter on them and would not rev over 6150 rpm. Also they needed to run at higher RPM's

to get the best service. And if they weren't they would make oil (some fuel would by pass the rings and get into the oil). I was wondering if anyone

had any input on this matter?

[johnr]

For your model, the Yamaha website will have specifics in the manual. That said...

Newer engines are Rev limited, so don't worry about over revving it. With a load, it needs to be able to run at the upper end of the WOT range in order to not lug the engine. If it bogs down when loaded down, less prop pitch or more power is necessary, as a bogged or lugging engine is unhealthy.

I tune mine to bump the limiter when loaded to fish with just me. Typically I run at a comfortable cruise speed, which is operator preference. On my current setup that is 4k rpm. I am NOT afraid to run wide open tagging the limiter if I need to. I don't make it a habit though, of course.

I feel that making oil is a product of improper break in. Proper break in, to me, is running ten hours (yamaha) with out shutting it down and always having a load on it. The rings gotta get HOT so they seat properly. None of my 5 modern 4 strokes have made a drop of oil.

I've got a couple thousand hours on a 2010 etec, and I've never done anything but run it wide open hammering the Rev limiter. Modern engines are, in general, fairly bulletproof.

[drag4striper]

Thanks johnr, I was a little unsure about some of the things I read on "the net". When I purchased the boat the hour meter had only 54 hrs on it (2009).

And I got very little in the way of manuals etc. with it. My old boat had a Honda four stroke and I ran it open throttle when needed and had no problems (2003).

I never had the Honda make oil either. I haven't turned the 115  more that 5500 rpm and planed out it will do around 45 mph. The prop was changed to a stainless

mercury vengeance 18-p and comes up on plain very well. I guess I need to visit Yamaha's site to down load a manual or buy one. The making oil didn't sound right 

to me and I was wondering about the top rpms. 

[johnr]

I'd say you are in an acceptable rpm range at 5500. My WOT range covers 1200 RPM on my yamaha. 6250 is max.

[formula180]

Just go to their site and plug in the year and model of your engine.

yamahaoutboards.com/owner-resources/owners-manuals