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TOP Speed run..... hmmmmm ..... Thoughts

N

Newport RI

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Yami F300 Q25, max rpm achieved 5600..... Max speed on speedo was 45mph, yet on GPS only saw 39-40......this with engine have trimmed up, full tank of gas and two total passengers both 200lbs. Handled great....but thought this boat would run a true mid 40's on gps. (45mph on gps). We were running with a donzi and few other quik boats. For that moment wish I got the F350! I know these boats do so many things great, I get it and for a tritooon pretty quick....but this topic is all about max speed! Just want to make sure all running ok and not leaving any mph on the table... Tx all
 
To me, for 300 HP, that sounds a little slow.
 
Granted mine is a GCW 2375 with .10 aluminumn toons instead of .08 (doubt that makes up for the extra 2 ft on a .08), but I get high 40's with the same load, I have a 250 SHO. Sounds slow to me too, for a 300.
 
I agree it should be higher, you didn't mention the water and weather conditions. If I remember, you run that beauty in a pretty big pond don't you? My top speed numbers were always when water was smooth as glass or as close to it. If you're out there running with the big boys, I'm pretty sure your body of water is usually a little rougher correct?
 
I have yet to run on glass, my #'s are in pretty choppy. I think I can hit 50 with glass conditions. We'll see.
 
Ocean, that said it was a calm day...boat was sitting right and waves were under a foot. Into and with the wind speed was the same... If rockie is doing near 50 with a 250 I hope I can get to a real 45 on gps...any ideas what to check 1st? Running smooth and at idle can barely hear that F300... Going to call bennington monday, anyone have a good contact name there by any chance? Tx all
 
I would call your dealer first and see if they can sort it out first, and you'll find out how good your dealer really is.
 
Newport RI said:
Ocean, that said it was a calm day...boat was sitting right and waves were under a foot. Into and with the wind speed was the same... If rockie is doing near 50 with a 250 I hope I can get to a real 45 on gps...any ideas what to check 1st? Running smooth and at idle can barely hear that F300... Going to call bennington monday, anyone have a good contact name there by any chance? Tx all
Click to expand...
Is the engine broke in? First Oil change.
 
Definitely call your dealer, sounds more prop/motor problem as opposed to boat problem, so Bennington isn't the one to be calling, yet. Did you try double checking your gps numbers with maybe a cellphone or handheld as well? At least if they read the same then you know for sure your speed numbers are right.
 
Stupid question. I'm sure you had your biminis down because no one go's over 15mph with them up as manufacture's recommend.

It would be Intresting to so a test. Biminis up top speed vs Biminis down Vs Bimins off
 
On the Q models, I would have thought that 100% of the boats were ordered with GPS speedometers. You may have the speed already if it's saying 45 mph and is a GPS unit.

Are you sure your speedometer is conventional?
 
That's a good point Bama, wouldn't the 300 be digital shift and also have the digital speedo? I'm not sure, or was that just the Verado's? Or am I just way off in left field?
 
I believe all the big Yammys are digital.
 
Bamaman said:
On the Q models, I would have thought that 100% of the boats were ordered with GPS speedometers. You may have the speed already if it's saying 45 mph and is a GPS unit.

Are you sure your speedometer is conventional?
Click to expand...
I believe they're all GPS now. Mine had a Veethree NMEA 0183 GPS receiver module tucked up under the dash.
 
First thanks all....

Yes 13 hrs on engine so broken in but no oil change yet...

I have a sport tower so bimini always up...

Good question, no sure if my gauges read gps speed (I will call dealer).... Also I just tried to check the garmin to make sure their is a difference and someone at the marina suggested that maybe my garmin gps is set up as nautical miles and not standard mph.. I need to check that.

Again garmin was reading 39+ and speedo was reading 45......

I haven't have my trim up past half.... Do many trim up past half way on the meter? I am on ocean so never super calm...

Thanks again for comments...
 
I have my trim all the way up.
 
The actual trim-able amount of trim on my gauge reads right at about half way on the Guage. If you play with it at the dock, you'll see once you go higher then that, the tilt portion kicks in. Raises the motor at a much faster rate for shallow water operation and trailering. You DO NOT want to run over maybe 2K rpms while in tilt mode. The hyd cylinders can't take the downward pressure the motor puts on it at high rpm. I think your gps settings aren't set to the correct miles per hour.

Good luck

Todd
 
Hmmm, now I can't remember which way it worked, if the digital gauges had a cable running from the gps, or if they ran through that NMEA thing Tom was talking about off the engine. I would still try your cellphone and see what it's reading says. It should give you a close enough number to negate one of the readings. Actually, now that I think of it, your gauges will be run off your motor, since you have the digital, you also have a bunch of other readings too correct? Like fuel consumption, oil pressure, and other cool stuff, the gps to the gauges was only if you chose analog gauges, they had a sticker on them saying the speedo was gps controlled, if the upgraded gps was chosen.
 
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