Mild WDK ROK Build

holygoat

Site Supporter
Location
Indiana, USA
Took the old dog to wave rave. Met some great guys, forgot the bloody wetsuit. I was cold as balls, but it was a good time. Sent it big off of a few waves and came down like a rock every time. Can't win em all, gotta keep at it! First time out in surf was a good laugh.

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Night before I slapped an ada head on it. Runs excellently. Probably the last mod I'll do before winter teardown. I think I'm gonna attempt a home ported 701 this winter. I have a spare motor and I'll need a project to keep me occupied, so I figured why not. Worst case scenario I learn something. Not a bad return for a few hundred dollars.

I'm probably going to use the yamanube templates and attempt a bit of 62t case porting based on what I've been reading up on and talking to others.

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Finally I was taking paint off the bilge earlier to make new tank mounts and... Is this a carbon hull?!

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holygoat

Site Supporter
Location
Indiana, USA
So I blew my top end up, I think I forgot a cooling line. As soon as I could feel it running weak I killed it, but I think it was too late. I could smell it. She was gone. Expensive licoriceing mistake but one I hopefully won't make again.

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So I need a top end with 6 weeks left of the season. One (three) quick calls to @Jr. and this ported top end appeared on my doorstep in three days. Top service from the man.

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Cleaned my chamber up in the parts washer at work. Looks good now. Took the ski out. 10-15m of great riding, nice easy break in.

And then it all came undone. Ski would run for 15 seconds and die. Paul thought I may be getting water into the combustion chamber - it only happened coincidentally as soon as I saw water from the pisser. In retrospect, this may have just coincided with how much fuel was in the carb. Checked my o-rings, looked good. Checked the exhaust gasket, didn't look great. Faced my FP manifold at work on the Bridgeport. Paul sent me a new one as well as a new base gasket since I checked that was seated properly too. My waterbox was rattling, surely that was it! Cut it open, baffle is loose. Okay, so I welded it back up sans baffle. Back to the lake, same issue. Take my jetting back to as before, same issue. Something is really weird. Changed my ignition coil, stator, CDI, SAME ISSUE!

Sitting at home ranting, my wife comes with me to the lake and sees me run and immediately says "Sounds like you aren't getting any fuel." "No no it can't be, I didn't even open the fuel pump side up! It's the same as I've been running all year!" Labor day morning, I decided I'm gonna get to the bottom of this. Pulled my carb off and...

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Fuel pump side was disgusting. Internal filter totally full of poop. In line fuel filter looked good. I've been running this carb since May with no issues. I canot believe it ever ran like this! Huge thanks to Paul. Worked with me through every issue, even though ultimately it was nothing to do with him.

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Next issue is finding a tank and paint. Honestly, the 550 tank fits so well, I might just get a repro Ty-n-Fly one. I tried an LS 4 gal and it was too big, I believe stock SJ is too big too. Not a huge fan of fitting stuff in this hull but it is what it is.

Glass, paint, re-turf, and improve my footholds this winter. And I will be moving the pole an inch or so back towards me. I'm running at the absolute longest setting right now and it's just long enough, I figured I can move it forward a hair and still have plenty of shortening adjustment. I'm thinking a plain white paint with black turf, and purple accents. Then I can add stickers over the top if I so choose to.
 

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I have a similar set up to you, WDK Rok with a 4 mil stroker and a b pipe, I just put a 2.25 gallon kart tank from Highspeed industries and it fits way better than what was in there (fx-1 tank), used the original mounting points and yamaha tank straps, tons of room to take the tank out with the motor and pipe installed
 

holygoat

Site Supporter
Location
Indiana, USA
I have a similar set up to you, WDK Rok with a 4 mil stroker and a b pipe, I just put a 2.25 gallon kart tank from Highspeed industries and it fits way better than what was in there (fx-1 tank), used the original mounting points and yamaha tank straps, tons of room to take the tank out with the motor and pipe installed

How is the rok with the stroker? The 550 tank is about the smallest I'd want to go, I do a few open lake cruises where I would be concerned about having less fuel.
 
How is the rok with the stroker? The 550 tank is about the smallest I'd want to go, I do a few open lake cruises where I would be concerned about having less fuel.
Just got the ski not long ago, only had it out a few times but it goes pretty good, the motor is an HPE built and ported 4 mil, definitely alot more jam than my 701 SN with a speedwerx pipe
 

holygoat

Site Supporter
Location
Indiana, USA
I don't have too much to add. I put my 735 Shredder top end on a set of 62T cases. Twin 38s, I did add a zeel which I'm looking forward to trying. Hopefully going to pick up a 10/16 hooker when I get the chance.

Ski is stripped. Turf is out. Ordering fibreglass soon and reinforcing the pole area. patching some holes, etc. Considering rockering the nose just to get rid of that ugly flat nose. Probably won't though.

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Gotta get rid of all the foam, do my glass work, sand her down ready for primer. Probably just gonna blow a single stage white down.
 

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Somebody made a nose piece that went on the front of those and made it look normal. I rode a rok once with a 5mm stroker motor and I didn't like it at all. Just smashed thru wakes and didn't want to barrel roll off a good sized boat wake. I couldn't get back to the shore fast enough. The rokR was the first WDK pos with an open bulkhead.
 

holygoat

Site Supporter
Location
Indiana, USA
Somebody made a nose piece that went on the front of those and made it look normal. I rode a rok once with a 5mm stroker motor and I didn't like it at all. Just smashed thru wakes and didn't want to barrel roll off a good sized boat wake. I couldn't get back to the shore fast enough. The rokR was the first WDK pos with an open bulkhead.
I can't speak on the rolling, but I haven't found it to smash through wakes particularly?
 
When I charge a 3ft wave to do a barrel roll, I don't expect it to smash thru the wave. It needs to climb the wave so I can get enough air to get around. I'm pretty sure ths wdk hulls were designed off an sxr so they handle better than they stunt
 

holygoat

Site Supporter
Location
Indiana, USA
When I charge a 3ft wave to do a barrel roll, I don't expect it to smash thru the wave. It needs to climb the wave so I can get enough air to get around. I'm pretty sure ths wdk hulls were designed off an sxr so they handle better than they stunt
Yeah I think the bottom deck is just a shortened SXR800. It's my first AM hull and I've liked it so far. I'm 80% just a lake rider and boat chaser.
 
Location
dfw
The ROK is different than the typical A/M stunt hull. The bottom is narrower and it has a ton of lateral grip. Most others are wide and slippery. I think a 650sx has more grip than a Rickter. Making your exhaust port larger will help power and hurt response. It will be more important to make sure the rpm is over 6800, higher rpm is required as the port is raised. Boring the nozzle will make it pull harder. For Good performance a pair of 44 carbs will make it pull harder, OEM 760 carbs will work. 46 carbs will work if you are looking to spend more money, and time jetting them. The number one most important aspect is NOT over loading the engine. All the other mods do little if the load is too high.
 

holygoat

Site Supporter
Location
Indiana, USA
The ROK is different than the typical A/M stunt hull. The bottom is narrower and it has a ton of lateral grip. Most others are wide and slippery. I think a 650sx has more grip than a Rickter. Making your exhaust port larger will help power and hurt response. It will be more important to make sure the rpm is over 6800, higher rpm is required as the port is raised. Boring the nozzle will make it pull harder. For Good performance a pair of 44 carbs will make it pull harder, OEM 760 carbs will work. 46 carbs will work if you are looking to spend more money, and time jetting them. The number one most important aspect is NOT over loading the engine. All the other mods do little if the load is too high.
I spoke to Paul, he suggested I pair a 10/16 with my setup. I'm running a set of OEM 38s for now because that's what I had. I'm hoping to use what I have for now and likely step up to a bigger overall driveline package in a few years.
 

holygoat

Site Supporter
Location
Indiana, USA
Parts are stacking up. 144 10/16 and a new Brandon SFA tank.

I might need to move my engine back, the pic is where it sits now. I can get a better photo tonight. I'm thinking about picking up a short GP800 midshaft and reglassing the engine mount bolt plates back when I do the glass work.

Any guidance or tips? The engine sits pretty far forward in the hull as you can see. The tank just about fits. I would be a lot more comfortable with a bit more space up front.

Last year I did stainless inserts in all of the aluminium plates glassed into the hull, so I could feasibly reuse those.
 

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Big Kahuna

Administrator
Location
Tuscaloosa, AL
I spoke to Paul, he suggested I pair a 10/16 with my setup. I'm running a set of OEM 38s for now because that's what I had. I'm hoping to use what I have for now and likely step up to a bigger overall driveline package in a few years.
I remember when the Hookers first came out, It was around 1776.............. LOL, More like 1476! That said, everyone was screaming get a 9/15...... They were running the old DASA cast cylinders, stroked motors........ I called Dave told him my spec. 84mm Big Bore 61X. His response "10/16". He was spot on. I later in life tried a 9/15, It bored holes in the water. Later had one pitched to 9.5/15.5, I had dropped back to an 82mm ported 61X. The 10/16 worked just fine with it, just tried to tweak it a bit with the custom pitch. If you have bone stock cylinders and pipe, 9/15. Any other mods, 10/16
 
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