189trx top end isn't what I've read it'll be??

[Jimmy3]

I have a new 2018 189trx with a 150 opti and a 21 pitch tempest plus prop. I have only put about 16 hours on the motor and I do not have a jack plate yet as I was deciding on which type I wanted (manual or hyd).

With a full tank, empty livewells, my boy and myself I'm only able to get about 5500 rpms and a gps speed of 52 mph. That is all my fishing gear loaded in the rear storage and prop to pad is 2.5 inches.

I'm honestly not to worried about top speed but a higher top end means better efficiency which translates to better fuel economy. I've read many times I should be in the mid to upper 50s what am I missing?

[BassCatBrad]

A hydraulic jack plate will help. My buddy is running the same boat with a hydraulic plate. He has 150 HP Optimax 2 stroke. He runs 59 mph with a 22p prop. Plus his boat has a 10ft Talon. His 1st 189trx had a 4 stroke 150 and it had a slow hole shot and would run 56-57mph. He wasn't happy with the 4 stroke.

[Jimmy3]

The boat jumps out of the hole, from a 3 mph idle to pad takes around 3 seconds

[jlg309]

I have that boat with a 150 4 stroke. Depending on fuel load, passengers, etc. I’ll see between 52-54 MPH. I have the same prop with no jack plate and have about 200 RPM’s left before the limit. If they made a 20” tempest I”d try that and a jack plate might help, but honestly I’m not too concerned about picking up 2 MPH. I cruise around in the 40’s most of the time anyway.

[DaveTTN]

Jimmy3 that does seem slow as I have a 179 TRX with a 2 stroke 115 with a 21 Laser II. I can turn it 5850 and 49.5 gps.

[wash84]

My partner has the same boat with 150 4s he has the jack plate and it came with a 23p tempest and its a dog no lift what so ever he’s trying a 21p here soon to try and get some lift out of the boats it’s running about 52 to 54 just pushing water.

[Jaredn]

It’s A BIG boat for a 150. Sounds about right to me.

[jjtriton]

Most 189TRX's without a jackplate run close to 55mph, a 6'' manual jack plate will pick the boat up 2-3 mph.

[Scud]

I have a 2017 189 with a 2 stroke 150 no jackplate with a 21 tempest plus. Motor top bolts in 2nd hole. Not sure on prop to pad. It will run 57 just me with all my gear and a half tank of gas. 2 people will run 54-55.

[itsahog]

I know my boat is different but a jack plate really helped my boat with a number of things. It gave me around 3.5 miles an hour to ~ 58.4 gps, but more importantly it pretty much eliminated all my chime. I did have to adjust it a few times, something else I discovered is my hot foot was not set to go wide open, again very little but some by adjusting that set screw on the hot foot helped a tad. Last thing is, my jack plate has a plate on the bottom, maybe called a stabilizer plate I’m not sure, but my boat stays on plane at a lot lower speeds now. Very happy I installed it. If you have a hot foot, I would recommend checking to make sure you are at WOT.

[Jimmy3]

If you have a hot foot, I would recommend checking to make sure you are at WOT.

I have already thought of that one, got just about an extra mile out of it that way. The boat is currently in the shop for its 20 hr service, maybe they will find some mechanical issue with it. I've had a heck of a time with that motor so far as it has been back to the shop 3 different times for running hot.

They told me that the motor never got above 178* so it isn't hurt. I'm starting to wonder about that with the lack of top end I'm experiencing. However, it has plenty of low end and midrange acceleration so I'm not sure about that. Just before they found the issue with the motor overheating I got about 5800 RPMs and 56 MPH BUT that was only me in the boat and it was a cold 33* morning and full livewels. I have a hard time believing that adding a 200 lb passenger but leaving the livewells empty will drop you back 4 MPH.

[Kayak]

I think you should hit mid 50’s without a jackplate. Try moving a little of your tackle weight to the front. Mine is a 2017 with 150 pro XS turning a 21p. I have a 6” manual plate and dual 10’ Talons. With empty wells and just me I hit 54-55gps. With 1/2 tank, me (220lbs) co-angler (230lbs), and both wells full, (and I carry too much gear)I only hit 48-49mph. I enjoy being on the front deck more than being behind the wheel anyhow. Make sure your motor is fixed perfectly and enjoy!

[Chautauquanuy]

I have a '14 Triton 18XS which is a saimilar hull. I dont have a jackplate either. I get 55-56 MPH tops with my Merc 150 Pro XS.

[Jimmy3]

They got the overheating issue resolved, it was something with the adapter plate gasket or something. When I got the boat back a few weeks ago (after they replaced every gasket in the motor) I ran it as hard as I could for approx 30 miles without issue and idled another 20 minutes in a no wake zone without issue.

Kayak, your speeds sounds close to mine. Perhaps it is just a weight issue. I haven't ran the boat with less then 3/4 of a tank. It's amazing to me how much better fuel economy I'm getting with this 18' boat and a 150 opti then I did with my old 15' tri-hull with an old 1978 85HP evenrude.

Anyway, I was just reading about people getting around 60 mph out of this combo and I figured I was either doing something wrong or something was messed up with the motor.

When I get the boat back from the 20 hr check-up I'll move some weight around and see what I can come up with. I may even possibly let the tank run down a little. LOL

[Riccochet]

I have a '14 Triton 18XS which is a saimilar hull. I dont have a jackplate either. I get 55-56 MPH tops with my Merc 150 Pro XS.

Same boat/motor with a 21P Tempest Plus worked by Croxton. Getting a jack plate and setting P2P to 3.5" and moving all my tackle to the front center compartment helped a lot. Just me, half a tank, empty wells and no passenger console I'll get 58-59 out of it. On a nice cold day with a tail wind I've hit 61.3. Warmer weather I'm lucky to turn 5500 RPM and usually see 56-57.

18XS and 189TRX share the same hull. These boats are setup finicky. Adding a little cup to the prop really helps get the stern up. Too much weight in the back also doesn't help.

[Jimmy3]

Thanks Riccochet I'll move my tackle up front and see what that does

[jjtriton]

If you can find the other 400 rpms, that will get you in the high 50's