Octane Octane Modifications

michael950

for me to POOP on!
Joined
Jan 16, 2006
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Location
Houston, TX
#1
I know there are some modifications that should be made to the Octane out of the box, some due to design flaws.


Here are a list of modifications that you might want to look into.


(I have no clue, but sure Randy @ Watcon (who is dealing with World Finals) and Prem1x could chime in).
 

Prem1x

Tinkering obsessed
Joined
Jan 17, 2006
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Location
Austin, TX
#2
The factory '02 handlepole is too long. Update to an '03 version (Standard UMI -2").

The '02's need bond flange cutouts performed on the tailing corners. You can search for the template or just imagine how water would want to flow out from underneath the bond flange at the rear and relieve the part of the flange that prevents flow.

The stock carbs have some linkage problem that Watcon has a fix for.

The stock CDI can easily be modified for additional timing on the curve.

You can run restrictors in the bypass fittings and stinger to lessen the cooling flow since it comes with stock with dual cooling.

The stock jetting is way off. Search for recommendations or call Watcon.
 

Prem1x

Tinkering obsessed
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Jan 17, 2006
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Location
Austin, TX
#3
Problems you may have:

Motor mount plates delaminating from the hull. Replace that epoxy with fiberglass and resin.

Gunwhale foam and tray area become fish tanks. The stock foam is pretty sparse in there. Cut out your tray and gunwhales and refoam. Put in footholds while your at it and one-way valve if you'd like.

Battery box rubs into fuel tank. Bend that sucker back before it causes a problem.

Electrical box cover leaks allowing components to corrode. I have no solution for this. Though you may want to switch to MSD total loss since the flywheel is a big heavy turd anyway (great for racing through chop but too heavy for freestyle) and replace the whole box with a pretty carbon mounting plate.

The hood comes off easily. Search for a mod to the hood brackets (tap and insert bolts). Replace the hood brackets with Watcon versions. Or fabricate hood straps.

The hood does not sit on the seal properly. I have no fix for this. Suggestions may include suck it up and don't leave your ski on the beach or fabricate new latching system that allows you to adjust the positioning.
 

Prem1x

Tinkering obsessed
Joined
Jan 17, 2006
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Location
Austin, TX
#4
Stuff you may want to do.

If your racing it, replace the railing bumper as high as you can and grind the flange down (up) as much as you can and still be IJSBA legal.

Drill, tap, and reposition the ball on the steering nozzle for more throw.

The stock carbs suck. No idle stop or low speed adjuster. Grind out your stock manifold and mount a set of 42's or buy another manifold and go Mikuni like the rest of the lemmings.

The stock ride plate sucks. Cut it back for freestyle or go Worx for racing. Get a Worx 201 intake grate. SJ grates will work with minimal grinding. SJ plates will work with a LOT of cutting and drilling.

All the normal Superjet-style mods:
Wet Wolf freestyle cone.
Adjust your FPP pipe for more low end.
Shortened turn plate.
Footstap(s)
Smaller domes for more compression.
etc.
etc.
etc.
 

RMBC Freeride

Vintage
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Jan 15, 2006
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Pueblo, CO
#5
Good stuff Prem1x, thanks. I am working on a list/rant of my fixes & suggestions. I'll try to catch anything you might have overlooked too...

EDIT: I will add my $0.02 now...

The major problem with the octane is not the hull design! I know nobody will believe me on this but I have now found it to be true!!. The biggest problem is WEIGHT - in several places... hull, engine, crank/flywheel & pump. And believe it or not, lack of weight in the hood - yep too light, affects handling too.

In 2001 I rode one of the Prototype Octanes in Havasu. I was totally impressed at the time. However when I received my Octane in '02, it handled nothing like the prototypes I had rode. Been trying to figure it out ever since...

So, the hull weighs a ton and combine that with the waterlogging that occurs and it weighs more. The pump is 100% stainless steel (not SS pressed into aluminum), very heavy. The crank and flywheel are very massive and therefore the engine doesnt spool up fast. But more importantly, it does not SLOW DOWN fast either. I believe this MORE THAN ANYTHING compounds the handling problems of the Octane. With a SJ, you chop the throttle and the engine slows down quick, slowing the ski and planting the nose, then you can turn it. The Octane on the other hand keeps on spinning the pump for quite a while, pushing you forward. And sice the hull does not lean or carve (more on this later) you are fighting the hull to make it turn, waiting for it to slow down. Now, add to that the massive weight of the entire ski and the momentum involved and you have a missle that likes to go straight and not stop!!!

Now, we have all heard that Octanes "do not turn" and do not lean/carve. I believe this is also mostly a weight issue. My lighweight Octane hull leans and carves ALMOST like a SJ. With all the weight mentioned, the hull rides low in the water until higher speeds. This increases the wetted surface area of the hull and puts alot more pressure on the very wide bond flange. The bond flange acts like training wheels keeping the ski flat whenever the (heavy) ass-end drops. hence the cutouts to reduce lift and drag in the rear corners.

One other issue that most people dont know about is that the entire driveline is tilted at a greater angle than a SJ. Essintially angling the pump downward which pushes the nose of the ski down (see wetted surface above). this was done to accomodate the Polaris engine which could not be mounted as deeply in the hull (at least not with the bedplate they designed). A trim nozzle setup greatly helps free up the nose. Although a pump wedge would work too for a fixed setup - but I dont know of any available.

Hood - ask any SJ racer from back in the day, and they will tell you that a lightweight race hood on their SJ made it harder to lean in the corners, and negatively affected handling. Same problem with the Octane, the hood is super light (and flimsy) compared to the heavy hull and motor. Having more weight up high gives a pendulum effect allowing the ski to roll more side-to-side. Now I would never add weight to my hood for freeriding, but for better "race handling" a heavy hood should help.

All of this was just a theory in my head until it was proven by my lightweight, Yamaha powered Octane hull! With the weight gone and an engine that has snappy throttle response the Octane hull handles like a dream. It is like a super-stable SJ hull. It rips corners, leans over almost as far as an SJ and jumps out of the water at will!!!

I know there is more to it & I will add more to this thread as I think of it...
 
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RMBC Freeride

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#6
Here are a few other issues I have heard of and/or already addressed on my Octanes:

-switched to a SJ hood latch and hood hooks, more secure
-switched to a SJ fuel tank, rounded corners make it easier to get in and out & no clunky sit-down fuel pickup
-switched to the older style Polaris flywheel cover, smoother shape and narrower for easier tank removal
-intake manifold is prone to cracking (although mine never did). I'm now running Novi 46's - ditch those Keihins!
-the hull leaks everywhere, seal it up and refoam (mine had nearly zero foam in it)
-Tubbies for heavy factory octanes, no tubbies for lightweight ones (its a surface area thing)
-Octane steering cable is super strong, but it has less throw than a SJ cable - does not allow you to use the outside hole on the turn plate. RN cable is the way to go.
 
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K

ko2

Guest
#8
Do any of you have any thought's on my octane handeling set up ???
Worx extended dominator ride plate & jet dynamic's intake grate....I am a lake rider & mostly jump boat wake's......I know I have scrubbed some top speed off the ski.....But I like how the ski now track's straight at WOT, vs other combination's which had the tendancy to make the ski dart (not chine walk) violently in one direction.....Thanx in advance for any input !!!
 

Melmack

(Timothy)
Joined
Jul 11, 2008
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27
Location
New Braunfels, TX
#9
Ok, all I can say is Damn! No wonder they stopped making it. I will say this though, I love the way prem1x's ski runs in the surf. It's a dream in choppy waves. The training wheels coment erlier discribes it beutifully. It took the chop out of our nasty Texas surf so I could actually enjoy the waves. I had no Idea it had all those issues. Whatever he did to it before must have fixed those issues.
 

onlyFX-1

Jace Forest...BRAP!
Joined
Jun 2, 2006
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935
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Lake Travis,Texas
#10
MODS TO DO TO A OCTANE-
(1) get a lightweight octane
(2)no foam
(3)no bulkhead
(4)total loss
(5)bigger carbs
(6)kart tank

that will make a GOOD flatwater octane=)
 
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Melmack

(Timothy)
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Jul 11, 2008
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Location
New Braunfels, TX
#13
Travis,

I'd say SBT's your best bet. I've been to the SBT shop, they have a great rig for cranks. I've built a ton of motors with those cranks and they are rock solid. Unlike Hot Rods, they are stronger than OEM and don't tend to bend easily. Both my Square and yellow Fx-1 have SBT cranks and you see how I ride em. No issues, yet. I have one crank that's still good after 10+ years.
 
Joined
Oct 10, 2006
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82
Location
baldwin ny
#17
never mind the seadoo sc in the pic the kawe box with the polaris ele in it is in front of the tray. its the only pic i have of it right now as my dog ate my data cable. lol parts 008.jpg
 
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