WHAT’S HOLDING IT BACK???

200hp Pro XS on 2018 Triton TRX18, smart craft and vessel view mobile, light load, 1 person, 1/2 tank gas. 2.75 ptp, 6” manual Jack plate. Something doesn’t add up.

24 Fury 69mph @5480
23 Tempest 62mph @ 5600
22 Enertia 65 @5860

Demand Linear checked twice, 100%

What else can possibly be stopping this from getting more rpm’s? It’s run smooth, great hole shot, strong mid but just won’t rev, full trim every test run?

Open to any possible cause, i just updated from 200 opti and this new motor just won’t pull up top.

This is the same gear ratio as the old opti than ran a 25 tempest at 5690-5700.

Boat set up, weight etc initially was the same, have tried moving weight around but there is very little amount of stuff in hand boat.

The new motor has had an inline canister type mercury fuel filter installed, that’s the only difference. I’m frustrated and would really like to hear what a possibility could be.

I give up trying to find the lost speed.

What was top speed with the old Opti at those rpms?

Try a 22 Fury, drop engine down approximately 1/4 - 1/2". You were over-propped at 24P, and the other two really aren't that great a choice for this boat.

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Originally Posted by EuropeanAM

Try a 22 Fury, drop engine down approximately 1/4 - 1/2". You were over-propped at 24P, and the other two really aren't that great a choice for this boat.

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Thanks Don,

I started at 3” ptp and went up 1/4, nothing much happened, maybe a tiny bit less chine. My concern is that I would have thought it should spin a 22 to at least 6-6100.

I agree they aren’t the best props and trying to get some more to test, but do you think those rpm’s should be higher for only a 22?pitch?

A friend of mine is running a 21 tempest plus on his 200 xs 4s to get the rpm

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Originally Posted by hog power

A friend of mine is running a 21 tempest plus on his 200 xs 4s to get the rpm

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This is what concerns me, that’s a really low pitch prop. Not sure of your friends set up or details but if it’s a similar boat to me, I would wonder why this engine has no top end

A 21 is a pontoon prop .Mercury has a problem somewhere your not the only one I have heard of this

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Originally Posted by hog power

A friend of mine is running a 21 tempest plus on his 200 xs 4s to get the rpm

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Do you know what kind of speed your friend is seeing with that prop at 6100 rpms? What kind of boat is it?

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Originally Posted by TOUCH OF CLASS

A 21 is a pontoon prop .Mercury has a problem somewhere your not the only one I have heard of this

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Two points here.1. I do believe there is an issue with Mercury’s 4S technology relating to the lower unit and props. Don is one of a few that has a grasp on what it takes to make the combination work but the learning curb is steep for the average boat owner. 2. Mercury’s new lower unit needs to go back to the drawing board. The design engineers didn’t factor in a lot of variables in their product that could impact performance. For example; the rubber plug/retaining ring blowing out underway or leaking creating a path for water getting into the lower gear box. A 2 S makes torque in the power band completely different than a 4S motor. If the lower unit gearing isn’t correctly designed to integrate with the engine’s power band then the prop will never be able to compensate for the gearing deficiency.

I believe Mercury is working through these issues but it’s going to take time.

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Originally Posted by thommo59

This is what concerns me, that’s a really low pitch prop. Not sure of your friends set up or details but if it’s a similar boat to me, I would wonder why this engine has no top end

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DaveTTN on here is running a worked Tempest Plus on his 18 TRX with 200 Merc 4 stroke. He has reached 72 solo so you might want to read some of his posts or pm him for his exact setup. If I remember correctly he turned it 6090 RPMs.

Based on his results I bought a Tempest Plus 22P as a spare but have not ran it yet.

I am no expert on these new motors but have read a ton because I am headed to a 225 ProXS 4S in the near future. What I have noticed is that typically you have to drop 1 or 2 inches of pitch when going from the same HP 2stoke to the 4S. It seems 4S want less pitch, the motor a little lower and less venting for hole shot.

Triton boats like to run with the PTP up high so that may be conducive to the "lack" of performance you are noticing. Just like Don wrote, get a 22P Fury. I personally would go back to basics and drop the PTP to 3.5" then raise a 1/4 at time until speed no longer increases or water pressure decreases. Keep an eye on your RPMs.

I was told Mercury is currently developing new props to work with the 4S engines. It might take a few years to reach the consumer....

The 24p fury prop that comes on this boat is too big. Idk why they send them out with these. Mine would run 70 with that prop but like the op only at like 5500 rpms. Hydraulic jp on this boat helps alot i adjust mine for the conditions alot which helps this hull will chinewalk easy. I ended up going with a 24p bravo fs. All holes plugged. Holeshot is instant and i have ran 71 solo medium load and half tank of fuel at 6000 rpm i figured close enough. Prop handles great too.

[QUOTE=1Holeshot;11487182]DaveTTN on here is running a worked Tempest Plus on his 18 TRX with 200 Merc 4 stroke. He has reached 72 solo so you might want to read some of his posts or pm him for his exact setup. If I remember correctly he turned it 6090 RPMs.

Based on his results I bought a Tempest Plus 22P as a spare but have not ran it yet.[/QUOTE

1Holeshot, I noticed that you are running a 24 Bravo 1FS on your Triton 18 TRX. What is your top speed and Rpm with that Prop?

[QUOTE=chasesfish;11489803]

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Originally Posted by 1Holeshot

DaveTTN on here is running a worked Tempest Plus on his 18 TRX with 200 Merc 4 stroke. He has reached 72 solo so you might want to read some of his posts or pm him for his exact setup. If I remember correctly he turned it 6090 RPMs.

Based on his results I bought a Tempest Plus 22P as a spare but have not ran it yet.[/QUOTE

1Holeshot, I noticed that you are running a 24 Bravo 1FS on your Triton 18 TRX. What is your top speed and Rpm with that Prop?

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With the Bravo 24 I can get 70 solo with 1/2 tank of fuel right at 6000 RPMs PTP 2 3/4" below pad. With 2 onboard 68.5.

I owe Triton TRXV8 (Roy ) for doing the research for this setup. He must have ran 4 or 5 props before settling on the Bravo 24 FS.

I had the good fortune of trading my Fury 23 for the Bravo in like new condition in an even swap.

If you decide on a new prop PM me for contact on best price.

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Originally Posted by chasesfish

Do you know what kind of speed your friend is seeing with that prop at 6100 rpms? What kind of boat is it?

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Vexus aluminum 20ft , not sure on speed.

Thanks for all the comments so far gents, good discussion. I know it’s tracked into a “best prop” discussion which looks like the clear winner is the Bravo 1FS 24. I had concerns why these motors seem to struggle getting the max rpm’s and my prop details were for this reference. Thanks to those that sent private messages, appreciate that. As for Fury’s I just really don’t like there handling and feel. Getting my hands on a Bravo 1 FS 24 here in Australia, we’ll that’s another issue.
Anyone have 1 for sale?

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Originally Posted by thommo59

Thanks Don,

I started at 3” ptp and went up 1/4, nothing much happened, maybe a tiny bit less chine. My concern is that I would have thought it should spin a 22 to at least 6-6100.

I agree they aren’t the best props and trying to get some more to test, but do you think those rpm’s should be higher for only a 22?pitch?

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I'd suggest editing your Profile to indicate your location. Probably good for us to know that you're in Australia. :thumb up2:

There's a lot of conjecture and mis-information being propagated about these engines/gearcases. There is no "flaw" that's requiring lower pitch props than were used with previous models- it's actually a considerable IMPROVEMENT in the efficiency of the gearcase and propeller combination, that has previously NOT been available (the previous G2-TM used on 3L Optimax models was perhaps the closest, but still not quite there).

Yes, a 22P will likely put the engine up into the recommended WOT RPM band, where it NEEDS to be.

I picked up on his location as Australia when I received a PM which opened with " G-day Mate".

I really enjoy listening to Aussies speak. They probably get a big kick out of hearing an old South Alabama guy speak too. :smile: