Elevation and top speed?

[Brad Dunn]

I have a 2016 242xe and top speed has never hit more than 45. Usually 43. Elivation is 2300 ft. I hear others over 50mph. Is is elevation? My old ar192 had a low top speed too?
Happy with power but more speed would be nice.
Once in a while under load the tacks are sometimes 200rpm different. Not sure if that's a big problem. Single lever mode

 

[PolarXJ]

Definitely elevation. I normally operate about 350 feet above sea level and can get 50-53 depending on wind and current. When I take it up to 4700 feet, I lose a lot of power and get up to maybe 40-42.

 

[txav8r]

There is a big difference between 4700' and 2300'. But temperature, humidity, and atmospheric pressure take a seat at the table as well. I kind of have my doubts that you should be seeing 43mph at 2300' MSL. I ran at Lake Powell in my '12 SX240, and while I was slower than I am at 700' MSL in Texas, I was still right at 49mph at Powell, two passengers, full fuel, dog, and plenty of stores...and Powell is just under 3600' MSL. 4700' is significant and the affect it has gets not only greater the higher you go, the percentage of affect is greater as the scale is not linear. Loading makes a big difference as well, and having boards in mounts, bimini up, lots of stores, all matters, and the biggest culprit is the wind.

 

[MrMoose]

My boat ran 48-54 mph at 205 ft (Lake Conroe, TX), and 43/44 mph at 3700 ft (Lake Powell, AZ).
I've heard that some folks have changed (or repitched) their impellers to run better at elevation. If anybody who has done this comes across this post, please chime in.

 

[ar240owner]

What rpm's are you guys hitting ?

 

[Brad Dunn]

7200 I think

 

[J-RAD]

I'm running at lakes around 4,500-5,700 and top out at petty much to out at 44 in my '16 AR240. That's usually a full tank and 4-5 on board. Didn't notice much or any difference at Powell. But is all too do with elevation. I have done the throttle body space & ribbon delete (there a good thread or 2 on this forum about the mod) it helps you puck up a couple hundred RPM lost to elevation. I think the rev limiter is 7800.

 

[Nauticajetter]

I boat at 5000 ft and on stock impellers only got like 6400-6800 RPM max ( if I remember correctly) . This limited my speed and hole shot greatly. I worked with my dealer and they submitted a claim to yamaha and had them replaced with high elevation props pitched for my elevation. It's transformed by boat. I now get to 46 on glassy water with a max rpm of 7650 -7700 and my hole shot will throw people's heads back. I would highly recommend repitching impellars when boating at elevation.

 

[Nauticajetter]

@J-RAD did you buy your boat from south valley? They usually send them out the door with high elevation impellers already installed from what I hear.

 

[J-RAD]

@J-RAD did you buy your boat from south valley? They usually send them out the door with high elevation impellers already installed from what I hear.

Yes, it was South Valley. So they probably are pitched like you say. I don't recall being made aware off it... it make sense for a dealer here to sell their boats set up properly for the elevation.

 

[Brad Dunn]

Is there a chart. What stock is and what props for different elevations. Would be great if Yamaha did it under warranty. Either way I would like to look into it. I boat at 2300 to 3000ft. But I am definitely not getting full rpm

 

[Nauticajetter]

No chart that I know of but most people send stock impellers to impros and tell them what you have modified ( intake, ribbon delete) and your usual elevation and they can pitch it to work the best.