Top speed for 125hp mercury 2 stroke

[Geeksquad21]

Wondering what the top speed for this motor can be i have 2002 lund 1700 angler and had the boat out the other day and was only able to hit 40.5mph with 4 150lb people onboard. The prop is 3 blade alum with 19p.

[Superduty]

Check a Merc manual to find out what your max RPM should be. If you are running below that max RPM there is definitely room for improvement. With four people and an alum prop I suspect you are getting close to your max speed. My guess is that 45 mph would be possible with a lighter load and propped correctly. A stainless prop will almost always improve performance. Good luck!

[RiverBassGuy]

Simply by switching to a stainless prop, you may gain 1-3 on the top end and probably a harder pull through the mid range. According to merc's HSOforum, the 150 two stroke runs about 5300-5800. Sorry didnt see any info on the 125, check your rpms

[Fredd]

I have a 90 Yamaha on that same boat and I get 36 - 37 GPS MPH with three 200 pound plus guys and all our gear. I toyed around with props and was able to pick up about 4 mph by doing this (I ended up with a Yamaha alum prop). I think that you should be able to push mid 40's for sure. I assume that you are trimming the motor and you are talking GPS speed???

[delcecchi]

I have a 115, basically same motor, on a 1775 provee and get between 40 and 42 mph all by myself (with kicker and 3 batteries)

So your performance sounds pretty close. Those motors don't like over reving, I am told. Something about the crank. 4800 to 5200 is rpm range as I recall.

This is the carburated 4 cylinder motor, right?

[Retro Active]

I have the same motor on a 17.5 ft Smokercraft. I can get between 42 and 45 depending on conditions with only two people, so yours sounds about right. These are carborated, 2+2 motors.

[Northlander]

If your getting about 40mph with 4 people in the boat your doing fine.

[marine_man]

I would agree- 40 seems about right for that combination. I believe the max rpm for the motor is 5250. Where are you running in relation to that at Wide Open Throttle?

marine_man

[bassNspear]

It will do over 40. should push over 45 mph, depending on gear and how many people you have in the boat.

[Geeksquad21]

Was out on sunday got My lund 1700 angler up to 42 GPS speed with just myself on boat Rpm was at 5400 so it must be maxed out.That was also full throttle.I like to trim motor watching my Gps to get to top speed.Looks like I'll need a different prop to gain more top end.

[sdstatekid]

I would think you should be able to hit 45 with that combo. My dad's 1700 fisherman with a merc 150 EFI hits 60 trimed up with just me in the boat. I know its 25 more hp but I would guess the fisherman weighs alot more than an angler.

[marine_man]

Based on that I'd say you could drop 2" of pitch and get your RPM back near 5250 and pickup a little speed.

You're holeshot will suffer, but I suspect that's not currently an issue.

marine_man

[boatfixer]

If anyone wants to learn more about how fast their rig can or should go, or props and boat speed in general, google up prop slip, boat speed etc. What you will find is physics 101. Any given pitch at a given rotation will only travel as far as physics will allow. Engineers like Marine Man can attest to this. Physics is physics. Now I know he will get all scientific with us now.

Go easy on me. Remember we are talking about fishing boats.

[marine_man]

Nah, no getting sceintific here, but you're right on Boatfixer. It's all about the mechanics of the system.

marine_man

[davesfriend]

That speed sounds about right. I have a 125 merc 2+2 on a 1750 sportfish, with all the gear and a full tank it is about 42mph. The funny thing is 98% of the time I am doing about 1.8mph on the kicker...