I/O or OB

Slip Away

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Joined
May 11, 2010
Messages
1,431
I would buy a Scarab or Chaparral Vortex Jet Boat over a Cheap-A-Ha jet boat anyday.

So what do the honks at THT recommend you buy ? Guessing it's an outboard.......
 

agallant80

Commander
Joined
Oct 25, 2010
Messages
2,328
I would buy a Scarab or Chaparral Vortex Jet Boat over a Cheap-A-Ha jet boat anyday.

So what do the honks at THT recommend you buy ? Guessing it's an outboard.......

I didn't post there. Hell if they knew my other boat was a Bayliner they would send me death threats. I post there to kill time or to play in the big boat sand box. This site (iboats) seams to be geared more twords lake boats or at least have allot more members who focus on lake style boats. If I did post there I would imagine the answer would be a fishing boat with an outboard.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
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Jul 23, 2011
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49,831
FWIW - we were wakeboarding behind a 3 person seadoo this past week. so a fishing boat with an outboard would work as well. then again, people have wakeboarded behind a rowing crew

https://www.youtube.com/watch?v=hmEsoAR5s10

If you are just learning, you want a flat wake anyway until you get the hang of it and get into some tricks.
 

ssobol

Chief Petty Officer
Joined
Sep 3, 2010
Messages
503
... will take the car motor over the outboard any day of the week. ...

The key here is "car motor". I/Os do have car motors installed. However, your average car motor is not designed to run at the high end of its range for long periods. Think about it, how much time does your car engine actually operate above half the max RPM? In my car the RPM is less than half even when cruising on the highway at 75 MPH. The engine when placed in a boat will operate for long periods close to the top RPM the way most people operate them. This leads to the I/O engines wearing out a lot sooner than the same engine in a car would.

OB engines are only used on boats and can be designed to operate well under the conditions that they are actually used.
 

oldjeep

Admiral
Joined
May 17, 2010
Messages
6,455
The key here is "car motor". I/Os do have car motors installed. However, your average car motor is not designed to run at the high end of its range for long periods. Think about it, how much time does your car engine actually operate above half the max RPM? In my car the RPM is less than half even when cruising on the highway at 75 MPH. The engine when placed in a boat will operate for long periods close to the top RPM the way most people operate them. This leads to the I/O engines wearing out a lot sooner than the same engine in a car would.

OB engines are only used on boats and can be designed to operate well under the conditions that they are actually used.

Jeeze I guess I'd better replace my inboard with an outboard, I wonder if the factory makes a kit. :eek:
 

kjsAZ

Chief Petty Officer
Joined
Jun 15, 2012
Messages
433
The key here is "car motor". I/Os do have car motors installed. However, your average car motor is not designed to run at the high end of its range for long periods. Think about it, how much time does your car engine actually operate above half the max RPM? In my car the RPM is less than half even when cruising on the highway at 75 MPH. The engine when placed in a boat will operate for long periods close to the top RPM the way most people operate them. This leads to the I/O engines wearing out a lot sooner than the same engine in a car would.

OB engines are only used on boats and can be designed to operate well under the conditions that they are actually used.

And the 4-stroke O/B's are what? Car engines too. They also don't like to be run at WOT all the time. That's only valid for 2-strokes and then you have the oil injection on all new 2-strokes.
For both types the car engines are modified anyhow to adapt them for boat use. If you use a "equivalent" car engine as a replacement they won't last at all.
My last boat had an O/B and the current one is I/O and it is a lot easier to work on the I/O engine. But that all depends on what engine size in what boat. Some are really cramped in = no access to anything but that can also be said for modern 4-stroke outboards too. All the EPA stuff doesn't make it easy to fit.
 

H20Rat

Vice Admiral
Joined
Mar 8, 2009
Messages
5,203
I would buy a Scarab or Chaparral Vortex Jet Boat over a Cheap-A-Ha jet boat anyday.

So what do the honks at THT recommend you buy ? Guessing it's an outboard.......

Have you looked at the scarabs and yamahas? I have, very seriously as I'm close to pulling the trigger. No comparison. The yamahas are WAY beyond the scarab's in fit/finish/features. Also, the scarab has the 4 stroke rotax in it. Nothing against it, but you better be on good terms with your dealership repair department, ESPECIALLY if it is supercharged. Yamaha's engines are bulletproof... (also looked at the glastron jet, very similar to the scarab. Nothing to write home about. All three of those share the same rotax engine/jet)
 
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oldjeep

Admiral
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May 17, 2010
Messages
6,455
Yamahas are pretty boats, did they finally figure out how to keep the cleanup plugs from blowing out?
 

oldjeep

Admiral
Joined
May 17, 2010
Messages
6,455
What are cleanup plugs?

They are some plugs in the jet drives inside the boat. You remove them to clear weeds. Unfortunately they had a really bad habit of blowing out on their own and filling the boat with water. My friend had a twin engine that kept blowing them. There are all sorts of aftermarket lock systems for the plugs, and I would hope that Yamaha actually figured out a factory solution to the problem.
 

gddavid

Petty Officer 2nd Class
Joined
Jan 4, 2010
Messages
193
Don't overlook the quality of the wake and I am not talking about size. A wake with nice clean edges and no white wash is way easier to learn behind than a big frothy mess of a wake that trips up new skiers trying to cross it or lacks a clean transition to pop off of. I have skied behind all kinds of boats and while a watersport specific boat is awesome, it isn't a must have. Most smaller runabouts that have a low dead rise are capable planning at lower speeds which is really important for beginners. There are a ton of factors that go into it but generally speaking the larger, taller, heavier, and higher the dead rise of a given boat the harder it is to pull a wakeboarder or skier across a wide range of speeds. Larger inboard ski and wakeboard boats are pretty flat on the bottom and the weight placement helps them handle well but your average 25' i/o or outboard will be halfway onto a plane, throwing a big frothy monster of a wake, difficult to maintain speed because as it starts to plane out it will surge ahead but if you slow down a little to adjust the bow goes up and speed drops really quickly. Because there are so many factors that go into it, you really need to just see for yourself how that particular boat does on the water.

For example: I would love to have a super air nautique or x-star but my little 19' bow rider with a 3.0 mercruiser does a great job because it runs nice and level at my preferred speeds and has a modest but very clean and crisp wake. My father's 25' walk-around is miserable to run or ride behind, sure it can do it but doesn't do it well. I have ridden behind jet skis but never a jet boat. The jet ski was pretty bad, the wake was incredibly narrow and the center was turbulent and bumped from the jet, speed control was a real challenge as well. I wouldn't rule out a jet boat but I would certainly test it out thoroughly first.

Bottom line: just because a manufacturer sells a boat with a wake tower or has pictures of it towing a skier in the brochure, it doesn't mean it does it well. This applies equally to i/o's and o/b's.
 

OrangeTJ

Petty Officer 3rd Class
Joined
Aug 16, 2012
Messages
95
I have a Yamaha SX210. Love it. Super easy to maintain & own. It's pretty much a matter of changing the engine oil and sparkplugs once a year and lubing the steering and gate cables & pivot points. There's no transmission, no bellows, no gimbal, no trim pumps, no power steering pump, no accessory drive belts.

I've never had a cleanout plug blow, though I have been able to use them to clear a sucked up ski rope and a hunk of bark that I sucked up in the marina in the spring. Our lake is fairly clean, so not a frequent occurence for us. A jet without the cleanout ports would have required pulling the boat out of the water to clear. For watersports, I will say that the center table of the wake is fairly rough and at certain speeds the lip of the wake is a bit washy. That said, most riders spend very little time in that part of the wake anyway. With a pair of 800 pound straightline sumo sacs filled under the port and starboard benches, the boat actually produces a pretty decent wakeboarding wake at 22 - 25 mph with plenty of ramp and height to support wake to wake jumps. With the bags shifted a bit, it can be used to wake surf at 10 - 11 mph. Boat accelerates very well for its power (mine is a lower powered version - 220hp vs the 360 of the HO models) - easily pulling 200+ pound boarders and skiers up with a boat full of passengers. It's faster out of the hole than it has any right to be, actually. Top seed is nothing too big - about 45 mph +/- 2 depending on conditions and load. HO models run low to mid 50s but also accelerate out of the hole like a scalded cat. Very responsive handling at cruising and WOT speed and, with dual engines and throttles it extremely manueverable at idle speeds. Swimdeck is awesome and makes a great place to just sit and lounge when anchored at the cove and makes a great entry platform when tied up stern to the beach.

Negatives are that the boat is pretty loud inside when underway. Actually, that's my primary dislike. Also, low speed requires a vigilant hand at the helm to keep on course. Easy to do after getting a couple of hours behind the wheel but it can make it hard to hand the helm over to a guest driver. I have Cobra Jet steering fins installed on mine, which give it pretty solid straightline tracking once above no wake speed, though not at all to the level of an inboard wake boat.

It's not perfect, but we've been very happy with our Yamaha and I'd definitely do it again. I'll be interested to check out the offerings from Chaparral and Scarab as well - particularly Chaparral. The big drawback I see with both of those is the lack of cleanout access, which could be a non-starter for me on a jet. For that matter, if a lot of my boating was in lakes with a lot of surface debris or vegetation, I wouldn't want a jet.
 
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