# cape horn performance



## floater1 (Oct 31, 2007)

I have a 92 cape horn 21 with a 92 yamaha 200 running a 15m prop tach went out but running around 5500 rpm before tach went out. Top speed is 29-31 mph per gps what are some of yall getting outta a similar setup thinking i may need a diffrent prop


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## inshorecatch (Oct 1, 2007)

Sounds slow to me my 17 with 115 runs 40 at 5500, but I have a smaller boat. That would be with full tank of gas, ice, gear and me and my son


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## JoeyWelch (Sep 25, 2009)

Floater I forgot to get that prop size for ya. I'll look at it tomorrow evening.


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## floater1 (Oct 31, 2007)

Thats what im thinking had shane come over and check everything out 120 lbs of compression goodspark on all cylinders new plugs carbs are good the only thing i can think would be left is prop its not bent.im going to replace fuelpumps this weekend just because they are original. Anyone got a good17m prop i can try


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## Reel Sick (May 4, 2009)

Try the prop shop they will let you try them out first to find the best pitch for your boat and motor. Good Luck


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## samiams (Feb 3, 2008)

i put a 15 on my 21 ch with an 200 efi and best i got was 35mph...with a 17 i got 40


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## aroundthehorn (Aug 29, 2010)

My 19 cruises at 26/27/28 @ 3750. I don't have a Yamaha, though, I have a Johnson ficht.

Don't run your motor that hard. I'd look into the prop.


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## Hydro Therapy 2 (Sep 11, 2008)

inshorecatch said:


> Sounds slow to me my 17 with 115 runs 40 at 5500, but I have a smaller boat. That would be with full tank of gas, ice, gear and me and my son


Ditto!


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## Starlifter (Feb 24, 2011)

21ft CC Modified V-Hull (18deg deadrise), Yamaha F150 w/ 15-1/4 x 15 Yamaha Saltwater Series Prop. The boat tops out at around 35-36kts (41 mph) @ 5800rpm

Normally, cruise though around 15-22kts (17-25mph) @ 2000-3500rpm


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## floater1 (Oct 31, 2007)

Should i try a 17m prop


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## JoeyWelch (Sep 25, 2009)

Floater mine is a 19-T 15 1/4 Saltwater Series II. 45MPH.


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## cuzmondo (Oct 1, 2007)

What RPM are you turning fully trimmed out now? What is your motor supposed to turn? I'm guessing it should turn 55-5600 RPM; if your not turning in the recommended range you probably have too much prop. I would think a 17P and 5500 should push you to about 40 mph.

Sorry, just re-read your post and see you stated you're turning 5500. Might want to check your tach/speedo too. I believe that boat should run faster than 31-ish at 5500 with a 200 hp motor.


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## floater1 (Oct 31, 2007)

I will know for sure friday putting in a new tack and gonna run the 15m and then try the 17m


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## Flatspro (Oct 3, 2007)

Wirelessly posted

I had a 94 21 cape horn with a 200 merc black max offshore and ran a 23 pitch prop and got well over 50 mph.


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## floater1 (Oct 31, 2007)

*cape horn perf*

flatspro how was your hole shot with the 23 pitch prop i dont have any trim tabs so i need an inbetween hole shot top speed


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## JoeyWelch (Sep 25, 2009)

floater said:


> flatspro how was your hole shot with the 23 pitch prop i dont have any trim tabs so i need an inbetween hole shot top speed


Floater you would not believe what a difference TrimTabs will make on that boat. You will wonder how you fished without them.

Not trying to derail but they are well worth the money.


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## DragonSlayer (Nov 2, 2007)

Seems like it should be faster than that. Try to borrow some different wheels, they get expensive trying to guess which one to buy. Go to a shop that specializes in props.... I've got suggestion for where to go, but they should have more knowledge than me.


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## Flatspro (Oct 3, 2007)

Wirelessly posted

With out trim tabs horrible but with manageable. I used the boat for fishing the ska on the east coast so I had it built for speed the only problem I had was I had to pull to 18" sea anchors to troll live bait do I wouldn't drown them.


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## floater1 (Oct 31, 2007)

That is my next purchase either new or used trim tabs


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## aroundthehorn (Aug 29, 2010)

floater said:


> That is my next purchase either new or used trim tabs


General question. How much would trim tabs cost + install on a Cape Horn 19 with a 150hp engine? Would it be worth it?


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## floater1 (Oct 31, 2007)

I have found new complete packages of 12x9 for 600 dollars that is suppose to be the ones for 19-23 single inbord or outboard


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## JoeyWelch (Sep 25, 2009)

You won't regret it. After you have them a while you will pull em up one day in a chop just to see what difference they make and say to yourself "How in the hell did I ever run this boat with out them".

Remember me telling you this.


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## DreamWeaver21 (Oct 3, 2007)

My 1997 21 CH with a 1997 225 Yamaha OX66 ran 45mph lite with a 17M prop that was pitched back to 16.5. It would run 40 with any reasonable load.

These numbers are with the motor trimmed up correctly and not dragging any tab.


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## floater1 (Oct 31, 2007)

ran the boat today im only running 5200 rpm at 30 mph per gps running a 15 m prop what is the diffrence in pitches to turn more rpm and get a little more speed


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## floater1 (Oct 31, 2007)

just got back from trying a 17m prop 5300 rpm @ 35 miles an hour what should i do next try a 19 pitch prop or take the 15 m and have it tweaked by accu prop or the prop shop


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## Hydro Therapy 2 (Sep 11, 2008)

If you get it worked make sure you get it cupped even if you have to pay alittle more.


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## DreamWeaver21 (Oct 3, 2007)

How much do you have the motor trimmed up?


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## floater1 (Oct 31, 2007)

I have tried it at all trim stages it runs best about 1 mark above half on the trim indicator yamaha digital gauges


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## floater1 (Oct 31, 2007)

Need some advice should i just buy a 17 pitch prop and run the 5300 rpms or should i take the 15 pitch prop and have it fixed to bring the rpms up to the required 5600 rpms and possibly loose the speed stuck between a rock and a hard place want more speed but dont wanna runin the motor


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## DreamWeaver21 (Oct 3, 2007)

That is where mine ran best too. About halfway or one above or below half on the gauge. Up to you on what to do for a prop. My 21 only had 25 more HP but it seems it was a good clip faster. Maybe it was because the 225 is a bigger block. Seems like you should be getting more RPMs out of the 15M.

Considering I took a 17M and pitched it back to 16.5 inches and had a bigger motor, I don't know if the 17M is right for you. I would take the 15M to accu-prop and see what they can do. It will be cheaper than buying a new prop.


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## steamin53 (Oct 17, 2008)

You might find this information helpful. It's a link to one of my posts regarding my cape horn 21 from another board. http://www.thehulltruth.com/boating-forum/252835-what-maximum-rpm-1999-ox66-250hp.html

From what I read in your post I'd say your doing pretty good speed vs rpm with the prop you have. The 200 hp Yamaha I replaced on my CH at 5K rpm drove it about 39 mph trimmed up as far ad I dared. Don't even ask why my 250hp produces the same speed at 5600 rpm. The assumption is that I have a 15 pitch prop... I actually haven't checked it to be sure but that's what it computes as factoring rpm and speed with a 10% slip factor. Perhaps the bottom paint has become rougher with the years.

I likely won't change props because there's no way I'll run at those speeds in the Gulf especially if trying to pull up on a swell in rough water.

Now that I think about it my speed with the 200 and this prop might have been a little less. Not 30 mph but not 39 either. I still think your doing pretty good with what you describe. 

Steve


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## SHO-NUFF (May 30, 2011)

Are you trying to race or fish?
I would "prop" the boat where the engine runs at the optimal RPM for fuel economy and plane rather than top speed at max RPMs. 

You have to give up one or the other, a good hole-shot or top speed. There is a "sweet spot". And I would recommend having the boat loaded with the average weight of a normal trip. That means persons aboard, coolers, tackle etc. 

If you prop it where it preforms great with only you and a six pack , you will not be happy with the performance with a few friends and additional coolers.


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## GSGATOR (Mar 15, 2010)

If you are looking for more speed then go to the 17,,, but dont run the motor that hard until your tach is back up


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## Aqua Uno (Dec 6, 2010)

Maybe this link will help.

http://www.rbbi.com/folders/prop/propcalc.htm


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## floater1 (Oct 31, 2007)

Too the prop to prop shop he showed me a good 15 and i compared mine to it both were yamaha 15m props mine had lost just about all the cupping going to pick it up and try it friday he says i should get my holesot and speed back plus up the rpm


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## floater1 (Oct 31, 2007)

Ok took the boat out still running 5300-5400 rpms but with just me i gained 5 mph now in the 35-37 mph range.loaded with 5 people 30 mph wich i can live with should i stick with this prop or try a smaller diameter 15 pitch prop


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