Terrible top speed

[jasonG]

My guess is your prop to pad is not where it should be. It should be below pad 3-4”. I assume your trim is fine cause without trim you’ll never get to 5700rpm with a 24p prop. However you may be getting to your max trim to quick.

watch some videos or read up on the proper way to measure your ptp and reassess.

as for your transducer it’s likely fine but I’d look into a transducer saver to mount it on the jackplate. To much liability of damage in that spot

like to see picture of your talon setup. When looking at the bottom of your talons each should be below the bracket by roughly 1” anymore and she will drag ass

[Kjensen75]

Are you measuring from the rear setback or actual boat pad?

Here is a pic.20210506_142011.jpg

[Kjensen75]

I think the prop shaft is to deep.
you have a hydraulic jack plate right?
if the cavitation plate is 5 1/2” below pad then the prop shaft is to deep.
If the prop shaft is to deep it will cause to much drag from lower unit.
drag from lower unit to deep will chop off mph
prop to pad is normaly close to 3 1/2”

Thanks for the response, this was what Nitro told the dealer to check
Prop should be a 23-24 Fury
Motor height should be set to 5 ½”. Level the bottom of the boat to 0 degrees, level engine cavitation plate to 0 degrees, run a straight edge from the very bottom of the keel forward to under the cavitation plate. The top of the straight edge should be 5 ½” from the bottom of the cavitation plate.
Check throttle linkage with G3 software for 100% available demand.
Check installed height of Talons, these could be dragging in the water.
Make sure there are NO transducers mounted on the bottom of the hull that can drag in the water.

[Kjensen75]

This was the dealer recommended jackplate height to match settings above.20210506_142019.jpg

[Kjensen75]

My guess is your prop to pad is not where it should be. It should be below pad 3-4”. I assume your trim is fine cause without trim you’ll never get to 5700rpm with a 24p prop. However you may be getting to your max trim to quick.

watch some videos or read up on the proper way to measure your ptp and reassess.

as for your transducer it’s likely fine but I’d look into a transducer saver to mount it on the jackplate. To much liability of damage in that spot

like to see picture of your talon setup. When looking at the bottom of your talons each should be below the bracket by roughly 1” anymore and she will drag ass

Thanks for the response, see Talon mount above. Will definitely do some reading/watching before I hit the lake in the morning.
I've driven my dad's 20 foot Astro with 200hp Mercury for years but with no jackplate. Never had an issue running it to the max though.

[Wichibass]

Mine did the same thing. It was the hotfoot. Dealer said it wasn't. Had another guy look at it.

[Kjensen75]

Mine did the same thing. It was the hotfoot. Dealer said it wasn't. Had another guy look at it.

I was hoping that was the issue but 2 separate shops confirmed it's installed and adjusted correctly.
I spoke to Don the main man for Mercury on here. He confirmed the boat is more than likely over propped and try out a 23p, possibly even a 22p. Now the issue is the dealers that demo props are all out of stock until January or so.

[Brewerbass]

There are a lot of z20s running 24 fury 3s. You may not get the rpms up to 6200, but most are getting best speeds from the 24.

[Mcjenson]

I was hoping that was the issue but 2 separate shops confirmed it's installed and adjusted correctly.
I spoke to Don the main man for Mercury on here. He confirmed the boat is more than likely over propped and try out a 23p, possibly even a 22p. Now the issue is the dealers that demo props are all out of stock until January or so.

I really don’t think throwing props at it is the answer, unless something is wrong with your factory prop. 5700 rpm with that fury 24 you should be doing nearly 70. Most guys are running the 24, I even heard one guy was running a 25 fury with a light boat and getting 75+ in a prop discussion. A 23 p might put you in a higher rpm range, but like it was said earlier, that doesn’t necessarily mean speed.

[Brewerbass]

A 23 might get you 200 more rpm? If your not getting speed now, is the 200 more rpm going to get you there?

[BMCD]

@ those RPMs he's spinning it. unless his tach is off.... Or he is way too high on P2P.

But even not trimmed up I can run better speeds @ said rpm.

have we just removed the ducer to eliminate that as an issue, you can just unbolt the ducer only and tuck it in the JP.

[MJS34]

I have the same boat except the stock manual jack plate. It will run those numbers barely trimmed. If I trim it up like you should it will be pushing 70 in a heart beat. I'm not in a hurry now days and have never pushed real hard or trimmed it all the way out. Has acted the same from 50's this spring through hot 100 degree days this summer.

[Kjensen75]

@ those RPMs he's spinning it. unless his tach is off.... Or he is way too high on P2P.

But even not trimmed up I can run better speeds @ said rpm.

have we just removed the ducer to eliminate that as an issue, you can just unbolt the ducer only and tuck it in the JP.

I have the VesselView module and RPMs are confirmed on that. Speed is via Hummingbird in dash
Trimming up after on plane, RPM and speed jump quick, but speed tops at about 55 and then will slowly tick up to 60, may e 60.7.
I was looking at other Z20 pros and the Talons are much higher. I remounted those higher and closer in. They were also missing the water deflectors so I ordered those and got them on. I should be able to take it out next weekend to try it again. If no change, transducer move is next. That will remove anything that could be dragging.

[JoePA]

After reading every post regarding this, the scariest part is the DEALER didn't even know how to set the boat up properly!! When they have to reach out to Nitro to get a base setting, that in my book is a huge failure. This should be 101 of owning a dealership.

With that being said I would have yanked that that transducer first thing and installed a through hull setup, eliminates that problem. Next find someone in your area that knows how to set up a boat or get a good prop to pad measurement of 3.5 below the pad and leave it there for a base run.

[Kjensen75]

After reading every post regarding this, the scariest part is the DEALER didn't even know how to set the boat up properly!! When they have to reach out to Nitro to get a base setting, that in my book is a huge failure. This should be 101 of owning a dealership.

With that being said I would have yanked that that transducer first thing and installed a through hull setup, eliminates that problem. Next find someone in your area that knows how to set up a boat or get a good prop to pad measurement of 3.5 below the pad and leave it there for a base run.

This dealer here is a joke. They have no idea about anything on the boats. When I told them this boat won't hit anywhere near 70mph, I was told the boat won't go that fast. Seems they just want to sell them and do routine maintenance. Really disappointed to say the least. The last thing they told me was "here's Mercury's number, maybe they can help".
Luckily there's tons of knowledge on these boards to refer too. The hard part is living in west TX, lakes are 2 to 3 hours away and can't test like I'd like to. Slow process but hopefully all these tips will help.
Boat prop center is 3.5 below pad right now so that will be the baseline next weekend now with the Talons raised.

[Pat Dilling]

This may sound like a silly question. By any chance have you waxed your prop? If so, don't do that! Causes the prop to slip in the water instead of gripping it.

[Fish Boy]

I have a 2018 z21 with a 250 opti pro xs. I have the exact same issue. I've been chasing this issue for the last 2 years. Even had a new power head put in last spring and still no help. I've tried 4 different props from tempest to bravos and settled with a 4 blade bravo. Have a hydraulic jp and prop was sent from my buddy who works for Merc at lake x for the racing department. I was also told it was a prop, prop to pad, hot foot or bad driving. Well it's none of those and we still can't figure it out. The boat runs perfect until it hits that magic 59 to 60 mph and just runs out of juice and it sits at 5780 to 58100 rpm. I'm not speed demon but knowing that something just isn't right bugs me. I'm almost starting to think it is not the engine.

[Mcjenson]

I have a 2018 z21 with a 250 opti pro xs. I have the exact same issue. I've been chasing this issue for the last 2 years. Even had a new power head put in last spring and still no help. I've tried 4 different props from tempest to bravos and settled with a 4 blade bravo. Have a hydraulic jp and prop was sent from my buddy who works for Merc at lake x for the racing department. I was also told it was a prop, prop to pad, hot foot or bad driving. Well it's none of those and we still can't figure it out. The boat runs perfect until it hits that magic 59 to 60 mph and just runs out of juice and it sits at 5780 to 58100 rpm. I'm not speed demon but knowing that something just isn't right bugs me. I'm almost starting to think it is not the engine.

Do you have spray by the drivers seat like this guy? Makes me wonder if the trim isn’t working under load or something

[Kjensen75]

Do you have spray by the drivers seat like this guy? Makes me wonder if the trim isn’t working under load or something

Mine when trimmed out, the spray is behind the driver's seat.
Seeing the post above on his 2018 makes me a little uneasy that it's not fixable.

[Kjensen75]

I have a 2018 z21 with a 250 opti pro xs. I have the exact same issue. I've been chasing this issue for the last 2 years. Even had a new power head put in last spring and still no help. I've tried 4 different props from tempest to bravos and settled with a 4 blade bravo. Have a hydraulic jp and prop was sent from my buddy who works for Merc at lake x for the racing department. I was also told it was a prop, prop to pad, hot foot or bad driving. Well it's none of those and we still can't figure it out. The boat runs perfect until it hits that magic 59 to 60 mph and just runs out of juice and it sits at 5780 to 58100 rpm. I'm not speed demon but knowing that something just isn't right bugs me. I'm almost starting to think it is not the engine.

I'm the same...don't need it to run that fast but maybe once in a while, but having a brand new boat with something off just doesn't sit right with me. Especially if I decide to sell it and move into another brand.