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Random Quote: To err is Human said the rooster as he climbed off the duck.
On two stoke engines I have been told by my dealer to run them hard on occasion to keep the power head clean. It is also a good way to know if the motor is putting out 100%. This must be a widely held notion because a friend with a Optimax had his dealer tell him he was not running it hard enough. Apparently the smart gages can record the percentage the motor has been run at various RPM's.
My 225 FS reaches the top of the operating range at WOT of 6000 RPM. I realize fuel economy suffers greatly at the upper range, but that is not what I am asking. Is it good to run these motors hard on occasion or is it better to baby them? Are FS motors being abused to run them WOT for periods of ten minutes?
The dealer did tell me to run Ring Free and I am doing that.
I will ask my dealer but basically that is asking one person.
I run my Yamaha 4s hard and easy. Sometimes I run WOT for 15 minutes to get to a trolling spot and then troll for 2 hours and run 20 minutes WOT back. 240 trouble free (and ring free) hours.
I was told by a Yamaha product engineer that you can run the new 150 4 strokes all day at WOT and that is what is best for the engine. Seems strange to me. I
think I will wait and be a little more conservative and let someone else tell me how their engine does with that type of operation.
IMO I go out of my way to warm it up before anything. I like moderation. I don't like WOT very much. I will run it harder on the way in like....15-20 minutes before as to "help evaporate" any fuel that may have mixed with the oil. I like cooling down too. I have a Yamaha F200.
Thanks for the replies. Mine is a Yamaha 225 on a 23 Parker SE. It seem to push the boat with ease and tops out at 6000 and 49 MPH with normal load of 2/3 guys and fishing gear. The load actually does not seem to make much difference in performance.
Cat man-
I am not going to hammer you at all, appreciate your answer. What you say seems logical, however, I am not sure that FS outboards are identical to typical car engines. Also the prop provides slippage that you do not have with some cars when you pop the clutch. This factor could make it a little easier on engine parts. I was told by a Yamaha rep that the engines were designed to run all day at 7000 RPM, even though they are recommending a limit at WOT of 6000.
I warm my FS up by starting it as soon as I get on board and letting it idle until everything is loaded. Also run slow for a long stretch in the marina. Cool down occurs naturally as I run back inside the marina.
Most of the time I cannot run WOT because of water conditions and most of the time I do not want to anyway because of running outside the channels in relatively shallow water.
Getting back to the car analogy, which I do not think is perfect. I once worked for a older Doctor who ran his big Olds 98 so slow his wife would give it to me and tell me to run it hard because the dealer kept telling the guy he was carboning up the 455 block with his poky driving. I was 19 years old and that was an awful job to have to hammer that big Olds.
Thanks for the replies. Mine is a Yamaha 225 on a 23 Parker SE. It seem to push the boat with ease and tops out at 6000 and 49 MPH with normal load of 2/3 guys and fishing gear. The load actually does not seem to make much difference in performance.
Cat man-
I am not going to hammer you at all, appreciate your answer. What you say seems logical, however, I am not sure that FS outboards are identical to typical car engines. Also the prop provides slippage that you do not have with some cars when you pop the clutch. This factor could make it a little easier on engine parts. I was told by a Yamaha rep that the engines were designed to run all day at 7000 RPM, even though they are recommending a limit at WOT of 6000.
I warm my FS up by starting it as soon as I get on board and letting it idle until everything is loaded. Also run slow for a long stretch in the marina. Cool down occurs naturally as I run back inside the marina.
Most of the time I cannot run WOT because of water conditions and most of the time I do not want to anyway because of running outside the channels in relatively shallow water.
Getting back to the car analogy, which I do not think is perfect. I once worked for a older Doctor who ran his big Olds 98 so slow his wife would give it to me and tell me to run it hard because the dealer kept telling the guy he was carboning up the 455 block with his poky driving. I was 19 years old and that was an awful job to have to hammer that big Olds.
I had it explained in a way that made sense to me.* The basic concept was:*
Machines are designed for ‘x’ duty cycles.* Duty cycles is a design target that says the product will work for at least a predetermined measurement, be it time, revolutions, on/off cycles, etc. under normal use which includes keeping within operating specifications and performing proper maintenance.* The designers of the equipment define normal use.* *
Operating the machine in other than normal use consumes duty cycles faster, and will shorten*its useful life.* I don’t know exactly what the designers definition of “normal” is for our outboards, but I know it isn’t to run at idle or WOT all, or even most, of the time.* *
So, if you buy the duty cycle concept, it makes sense that to do either excessively will shorten the useful life of a motor. Tom
Although I wouldn't want to do it on my own motors, I can beleieve the new 4 strokes are capable of 6000 for a long long time. Many 4 stroke motorcycle engines rev to 13,000 right off the showroom floor so 6000 to them is barely running. My belieif is one of the best benefits of 4 strokes is they are much much less likely to fail from the reasons 2 strokes fail. Carbon or fuel problems resulting in powerhead failure. 4 strokes are not known for failing due to carbon problems and why should you worry about carbon problems in a 4 stroke when it is obvious that car engines don't have any carbon isssues. Carbon issues are mainly related to 2 strokes and especially DFI 2 strokes. This is the main reason I believe 4 strokes are going to get so much more popular in the near furure. For fishing purposes a 4 stroke has no issues idling forever. Some 2 strokes do ok idling forever, but many load up, carbon up, smoke, cut cylinders out to save fuel, and they just generally are not happy idling forever. I believe 4 strokes are typically going to outlast 2 strokes by miles as time goes by. But it will probably still be a application thing that makes one type better for on application ove rthe other. Speed will always be rules by 2 strokes, but durability is probably going to be won by 4 strokes unless you are talking abuse which will then probably go back to two strokes ruling again. But for cruising and trolling a 4 stroke is just plain made for that and has never had any issues doing that. I look forward to repowering in a few years to 4 strokes and leaving the powerhead failure possibilities that are to common with two strokes. I have not heard of a single 4 stroke powerhead failure ever, I'm sure it has happened but it seems very uncommon.
I asked question because I do not know for sure, but I have owned a variety of outboards for 40 years now. So I do have opinions on the topic. Your answer is the closest to what I believe.
The way I look at it is that if my WOT is 6000, it should not hurt to run it 4000 to 4500 at cruise. That is faster than I ran my TS's but they topped out at about 5000 RPM. AT 4500 I am running 35 MPH and still have 1500 more RPM to WOT. Time will tell. The five year warranty is comforting. Will probably replace the motor or entire rig between four and five years. Yesterday I had occasion to want to get somewhere in a hurry and ran about ten minutes at WOT. That will be pretty rare.
i am probably wrong but i thought they goverened the two strokes much like
disels. so they want turn but so high ....... maybe it s just what i wanted to
hear so i can run it as hard as i want
I agree with a lot of what I just read. I remember the first time I saw that cut away F225 in Miami, I thought there's way too much stuff in there to break... I also noted how few powerhead failures I hear of with them, and I do believe it'd make headlines on any one of the forums when it does happen. I haven't run mine WOT continously for more than 5 minutes or so, but I do cruise at 4500-5000 and think little of it. I buy the importance of warm-up, I think it's most important thing I do for the motor every time I use it... All those parts, a lot of different materials, all with tolerances designed for 'operating temperature'...
As for the car analagy, okay, I buy into the lack of need for ring free, but I still will use it as prescribed. But beyond that, I don't know. I figure 5000-6000rpm on the boat is the max load I give it.. But on my Tahoe, I think towing the boat back and forth from NJ to FL at 79.5mph is the hardest work it ever does (fuel consumption proves it too ) and it is only turning like 2300rpm...
I gotta think the car engine and the outboard engineers did their homework, they both work.
So much for y $.02
Most engines have an "operating range" that is set by the manufacturer, that is the rpm range that most of your boating should be done in, cruising, etc....WOT occasionally is OK and can help in blowing out carbon etc, to run all the time WOT isn't a good idea, either for economy or longevity....Mick
WOW! Must have been an exciting ride. What is your reasoning for running the four strokes WOT so long. Not being argumentative. Just trying to learn. Is Yamaha a sponsor of yours that provides the engines?
Four Strokes--Run em Hard or Run em Easy? 
....... maybe it s just what i wanted to 
) and it is only turning like 2300rpm...
