I/O vs OUTBOARD

Chris1956

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Re: I/O vs OUTBOARD

Thumpar, Fair enough. A center ski eye is more convenient than a bridle. For towing tubes and such on my OB 21'footer, I only attach to one stern eye anyway. For skiing on my 16' OB speed boat, I use a bridle.
 

JimS123

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Re: I/O vs OUTBOARD

That's pretty cool pulling a skier with that small motor. I presume it is mounted on a canoe?

I skied behind a 4HP Merc on a aluminum rowboat. Of course, my ski was a picnic table top....

For the record..I/O usually make far larger wakes than outboards. Any experienced skier prefers skiing behind an OB for that reason.

Back in the 1950's all we needed to ski was a 25. If you had a runabout with a Evinrude Big Twin you were at the top of your game.
 

southkogs

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Re: I/O vs OUTBOARD

Hey OP! Since the fuse made it all the way to the I/O vs. Outboard powder keg: Is skiing THAT important to you?

IMHO - the OB vs. I/O argument stalls out when someone says, "I'm BIG into skiing." Hands down at that point, you really want to look for a dedicated ski boat (for example: a Mastercraft Inboard). The hull/power combo is designed to drop the right table for skiing, and plenty of power to getcha' up outta' the water.

BUT ... if y'all are just skiing and tubing for fun, then the whole thing goes back to a "whaddya'like better?" proposition.
 

Chris1956

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Re: I/O vs OUTBOARD

Bubba, Ballast bags are used to increase the wake for Wakeboarding. Slalom skiers like nice flat wakes, and obviously don't use ballast. Even non-professional, but experienced skiers (which I am one) prefer a small wake from a light OB-powered boat, versus the 2' wake from your average 18' I/O powered runabout.

A professional-grade waterski boat would obviously be better, but if you can only have one boat, and you are not a professional skier, I think the OB choice is best.
 

Scott Danforth

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Re: I/O vs OUTBOARD

Here is my take since I am out of popcorn.

the OP is from SE Wisconsin. unless he is wearing a wet suit, best he is going to do is ski from late June to September. with a wet suit and dedication, April thru mid November.

that being stated. if your a hard core skier, you have a ski boat not a run about

since the OP has been dealing with bow riders in the 16-19' range he is in a small run-about and not a master-craft or correct craft or a ski nautique. Bow riders are not ski boats. they are runabouts. since the OP is looking at another bow rider, and the majority of bow riders have I/O's get a boat that you and the family like no mater what the motor type is. you need prop torque to pull a skier up and out of the water. for an I/O a 3.0 is marginal at best even with a 15p prop where a 4.3 or larger is recommended. Almost any boat will work for a weekend skier that just likes to ski if it is set up right. I have skied behind a 12' tinny with a 18hp johnyrude, a switzercraft with a 150hp tower of power, a bunch of ski boats with OB's and with direct drive, and every bow rider run-about in the family. Bow runners make a concession in trying to be a bit of everything to everybody and that is ok.

However regarding the OP's original question. there is no comparison. HP is HP. where that HP falls on the torque curve is the key.

an OB makes high RPM power (low torque curve) where an I/O is usually limited to 4400-5000 RPM and usually has more torque at a lower RPM.

Since both the OP and the I/O are connected to a prop with a single gear ratio the issue lies in the correct prop for the application. I have repeatedly posted that I run a prop for water sports and a prop for cruising. in most instances (both I/O and OB), this is a requirement to get a good holeshot for watersports and get a reasonable top end for cruising. It is the boat setup that makes the difference.

Its not an OB vs I/O issue. its a proper application of the available torque coupled with the hull design in the setup that makes a difference.

Buy an OB, buy an I/O. doesnt mater as long as it can be setup properly. as far as one is better than the other, I would need more popcorn.
 

Chris1956

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Re: I/O vs OUTBOARD

C'mon Scott, We always skied in cold water, and never had wet suits. Wear sweat pants and sweatshirts, and roll up the pant legs. Now do a jump start off the beach, ski like a madman and a beach stop. You hardly get wet. Heck my friend used to ski in sweatsocks.
 

Scott Danforth

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Re: I/O vs OUTBOARD

C'mon Scott, We always skied in cold water, and never had wet suits. Wear sweat pants and sweatshirts, and roll up the pant legs. Now do a jump start off the beach, ski like a madman and a beach stop. You hardly get wet. Heck my friend used to ski in sweatsocks.

I used to jump off the doc, until one time either my timing was off, or my buddies timing at the throttle. eitherway, I hit the doc, then was yanked out of the skis into 45 degree water. and that was in May. Still trying to figure out how much anti-freeze I had in me to do the two polar bear plunges.
 

Home Cookin'

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Re: I/O vs OUTBOARD

I agree with Danforth's well-reasoned opinion that it's all about torque and thuis proper prop, sufficient power (and correct hull design and weight distribution) but I would add one crucial detail--as long as it's on an outboard.
 

Tail_Gunner

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Re: I/O vs OUTBOARD

Well this is a deep subject volumes could be written and then's there's application's...Keep it simple O/B's are quite simply expensive and ugly....:fencing:
 

Scott Danforth

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Re: I/O vs OUTBOARD

I agree with Danforth's well-reasoned opinion that it's all about torque and thuis proper prop, sufficient power (and correct hull design and weight distribution) but I would add one crucial detail--as long as it's on an outboard.

I agree if its on a Seven Marine 557, or maybe a pair of them
 

ggundersen3

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Re: I/O vs OUTBOARD

so bottom line....is a 18' sea ray bowrider with a 135hp mercury outboard with a stainless prop going to do a decent job pulling up average size (150-200#) above average skiers?
 

oldjeep

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Re: I/O vs OUTBOARD

so bottom line....is a 18' sea ray bowrider with a 135hp mercury outboard with a stainless prop going to do a decent job pulling up average size (150-200#) above average skiers?

If they are average skiers then it should be fine. The only time you need power is to get the guy out of the water and if he knows what he is doing then no problem. Once you are up, you would be fine with 60HP ;)
 

Scott Danforth

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Re: I/O vs OUTBOARD

so bottom line....is a 18' sea ray bowrider with a 135hp mercury outboard with a stainless prop going to do a decent job pulling up average size (150-200#) above average skiers?

yes, however you may not be able have 4-5 people on board. you will have to find out as you set up your rig. you may need to change props between one for cruising and one for watersports. however it will do a decent job.
 

Chris1956

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Re: I/O vs OUTBOARD

You should be able to have a good Slalom run with an 18' runabout w/ 135HP motor. Run about 34-36MPH (s/b 3/4 throttle), as the skier likes, fast enough to make the skiing nice and light.

With an experienced slalom skier, on the last 25-30% of the course, I crank my speedboat up to near 40MPH. Helps them to "rock and roll" in the "anchor" portion of the course. And in addition, if it is your wife skiing, it makes them "putty in your hands", afterward.
 

H20Rat

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Re: I/O vs OUTBOARD

With an experienced slalom skier, on the last 25-30% of the course, I crank my speedboat up to near 40MPH. Helps them to "rock and roll" in the "anchor" portion of the course. And in addition, if it is your wife skiing, it makes them "putty in your hands", afterward.

You would drive for me approximately ONCE before I would never let you drive my boat again! I've had people who I thought were experienced drivers pull me like they would if they had a tube behind... They aren't allowed on the boat anymore either.

Here is how you drive... Punch in 32 mph in the perfect pass. Do not touch the throttle until I let go of the rope, and drive absolutely perfect straight lines until you have to do a 180 degree turn, back on to your own wake.
 

RotaryRacer

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Re: I/O vs OUTBOARD

My 18' Four Winns with a 150HP outboard will yank just about any experienced skier out of the water. It has surprised a few people who thought dedicated straight drive ski boats were the only way to ski. It yanks them up just as fast. With the ski pylon just in front of and above the motor the angle of pull is similar to a center pylon in a low freeboard/flat bottom tournament boat. Hits a nice steady 31-33 mph and tracks almost as well as a ski boat.
 
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