Top Speed RPM Question

[rkgdmd]

If you aren't hitting top rpms you need more power or less pitch on the impellers. It is a guessing game and elevation can certainly play a factor. Try for more power by doing a couple of the riva mods or pulling off your filter and see if it makes a difference.

Or it could be a problem similar to my 2015. Throttle cables adjusted properly, but ECM only opening throttle body part of the way...in my case 80%.

 

[Speedling]

Ecm can limit throttle body from opening? Is new engine fly by wire after they run cable all the way there? If so that is ridiculously over engineered.
In any case, if the ecu is limiting the opening of the throttle body, I wonder if there is any type of adjustement on the throttle body as well so you can advance it ahead of the ecu. The problem will be the computer will run ittoo lean.

 

[rkgdmd]

That is what appears to be happening in my case. The dealer is supposedly contacting the engineers at Yamaha to determine the problem.

 

[Huskerjetboat]

Found my problem. Flipping California boat bought in MN. Would have been nice River Valley Power Sports in Rochester would have told me. And when I called they acted like they had no idea what was going on. Lost a lot of respect over this. Not really very happy about it.

 

[Kennc]

@Huskerjetboat trust me when I tell you I have felt the way you feel.

 

[Scottintexas]

wow that stinks! did you check the sticker on the port side all that lists the max kw/hp also ?

 

[Huskerjetboat]

wow that stinks! did you check the sticker on the port side all that lists the max kw/hp also ?

No, not yet, but I will. Pretty sure after reading some previous threads that this is my problem. What bothers me is that I was not told. We did get a good price, but I thought it was because it was a leftover 2013, and the 2015 were coming out in only a couple of months. My wife is like "it's plenty fast" but....I'm a guy, and plenty fast is not fast enough. Just pains me. And if I would have been told up front, and that is wart of why I'm getting the good price, I'm not sure if it would have blown the deal. I prefer honesty up front. Having doubts as to ever buying from this dealer again.

 

[Huskerjetboat]

To top it all off, the salesman I worked with is a member of this forum, and I have been in touch with him about this issue, and he has not come forth with any answers. When you sell as many boats as they do, I seriously doubt you do not know about this issue. Just be honest, don't play me for a fool.

 

[hoppersteven]

I bought from this same dealership at the boat show in January and I have not had the best experience with them either. I bought from a sale man's out of the redwing office but had to deal with the rochester office which was actually a improvement. I believe you are talking about garret and if so he was the one who did finally help but it was not quick at all. I was told a lot that they would call me the next day and not one time did they ever call me back. I would always call back a week later and get the same run around. The stuff I was dealing with was with the JBP stuff. I do have a short list of warranty work that will need to be taken care of but I will wait till the fall to deal with that

 

[Speedling]

So how do they attain this certificate? Extra catalytic converter? Easy enough to get the regular parts and swap I would think.

 

[rkgdmd]

So how do they attain this certificate? Extra catalytic converter? Easy enough to get the regular parts and swap I would think.

Unfortunately not that easy....or that cost effective. In addition to removing cats you need an entirely new ecm. Another jet boater on the other forum priced out the parts and it was prohibitive. Also...no more Yamaha warranty. It's a real bummer.

 

[Livi0411]

Found these certified test results on a 2010 242 Limited S in Boating Magazine. It's a good benchmark for anyone concerned with RPM/Speed ratio.

 

[Noko]

Were there CARB boats in 2013?

Yes. I have a 2013 CARB boat. My lake elevation is about 1,200msl. I get 7,400 rpm starboard engine and 7,200 on the port. I have hit 48 with just me in the boat and smooth water. I do think I had the bimini down when I hit 48. I adjusted the throttle cables so the throttles are at the stops in the engine compartment. The lcd display says the max speed of my boat at some time was 52 and I guess that was tested by Yamaha. It would probably hit 52 if I emptied the boat of all excess weight and went on a smooth day, and lost a few pounds myself.

 

[Noko]

Unfortunately not that easy....or that cost effective. In addition to removing cats you need an entirely new ecm. Another jet boater on the other forum priced out the parts and it was prohibitive. Also...no more Yamaha warranty. It's a real bummer.

I get 48mph on my CARB boat and for another 4mph or kts, I can't see messing with the boat just to get that little extra. And, I don't run at WOT for more then about 5 min on our lake so why bother.

 

[Noko]

View attachment 25038
Found my problem. Flipping California boat bought in MN. Would have been nice River Valley Power Sports in Rochester would have told me. And when I called they acted like they had no idea what was going on. Lost a lot of respect over this. Not really very happy about it.

These guys pulled the same crap on me. I didn't know what to look for and ended up with a CARB boat. I was pissed. But I had mods done by the dealer and I love the boat. I don't really care that I top out at 48 vs 52, I don't run WOT that much. My boat still hauls butt from 0 t0 30 and that's where I operate the most.

 

[Mc2871]

I have a 2014 SX 240. Only able to get 7000 rpm and 42 mph.
Elevation of 730 ft.

 

[Jonathan Pisarczyk]

My 2015 AR240 is only getting 7200 on the Port and 7100 on the Starboard. I just triple checked the oil level and changed the plugs. Is this ECU limiter possible for extra break in? I've got 22 hrs or so.

 

[rkgdmd]

My 2015 AR240 is only getting 7200 on the Port and 7100 on the Starboard. I just triple checked the oil level and changed the plugs. Is this ECU limiter possible for extra break in? I've got 22 hrs or so.

See if your boat is a 3 star or 4 star emission boat. The 4 stars have additional emission equipment and don't really run to 7500 RPM. My 2013 Limited was a 4 star and I could only get about 7050 max from each engine.

Some BRP Rotax engines do have a ECM controlled RPM limiter. The boat would not run above a certain RPM until a given number of hours was obtained. I do not believe Yamaha has this feature though.

 

[Jonathan Pisarczyk]

I've got the 3 star motors!

 

[robert843]

Took my 2011 sx240 out tonight only hit 46mph as well. I didn't pay attention to the Rpms but that was with 8 people on board and 3/4 tank of fuel. Does that sound about right for a top speed?