750sx Freestyle Build 1100cc

[Reckless83]

So I bought a 94 750sx which was mainly just a hull and a few parts. The idea is to build a 1100sx Freestyle. Pictures are of work done so far. I will upload more as I progress through the build.

 

[Reckless83]

More pictures

 

[Quinc]

Looks like an interesting build! Are you sticking with the 750 140mm pump or going with a Kawa 148?

 

[Reckless83]

Looks like an interesting build! Are you sticking with the 750 140mm pump or going with a Kawa 148?

Not sure have a very nice 140mm setup with trim to put in it. What is all involved with going to 148mm?

 

[WFO Speedracer]

Not sure have a very nice 140mm setup with trim to put in it. What is all involved with going to 148mm?

https://www.pwctoday.com/forum/technical-discussion/vintage-skis/kawasaki-x2/196913-148-mm-pump-into-an-x-2

 

[fastgtfairlane]

1100s are cheap Power but not good for freestyle. They're known to destroy crankshafts from water ingestion which is inevitable with freestyle riding. And they're heavier. You're better off with a properly built and setup twin cylinder engine for freestyle.

 

[Reckless83]

1100s are cheap Power but not good for freestyle. They're known to destroy crankshafts from water ingestion which is inevitable with freestyle riding. And they're heavier. You're better off with a properly built and setup twin cylinder engine for freestyle.

Thanks for the advice, but still gonna stick with the triple for now as I have 1 900cc and 4 1100cc engines laying around. I'm in the process of pulling a mold off of the hood to make one out of carbon fiber to lighten the ski up. Looking at every option to lighten it up as possible.

 

[Quinc]

Are you going to do any mods to the 1100?

 

[Reckless83]

Are you going to do any mods to the 1100?

Yes, so far all parts have been ported to match gaskets. Big bore with Wiseco pistons, gonna do carb swap if needed. Mainly working on the hull at the moment, will get motor all together when done with it.

 

[Reckless83]

After the 148mm pump was brought up by Quinc I decided to do some tinkering. This girl is going to be fitted with a ZXI 1100 148MM pump. Gonna work out like a charm. Using one of my junk 148mm pumps as the test subject. Pictures will be posted when I get a the work finished so gonna be a few days.

 

[Reckless83]

Got a questions about dual cooling. Has anyone ever install dual cooling with one line solely to the engine and one line solely to the exhaust system. I was thinking about using a soild gasket on the exhaust to separate the two from each other. Maybe drill and tap the lower part of the cylinder for the in and have lines out on the top of the head.

 

[Reckless83]

So I got the pump 148mm mounted and most of the work done on the trim system. To mount the pump I cut open the hull and used 3M DP420 epoxy to secure the thread inserts. Still waiting on my new ProWatercraft pump shoe.

 

[fastgtfairlane]

I typically separate the exhaust and engine cooling on every ski I put together. My current ski has 2- 1/2 lines from the pump that go into a manifold with 4 3/8 outlets. 2 outlets feed the engine to 2 separate pissers, 1 feeds the headpipe to another pisser, the 4th line feeds the stinger with a flow control valve set to open around 1/4 throttle. Setting it up like this enables the use of restrictors to fine tune your ski.

 

[Reckless83]

I typically separate the exhaust and engine cooling on every ski I put together. My current ski has 2- 1/2 lines from the pump that go into a manifold with 4 3/8 outlets. 2 outlets feed the engine to 2 separate pissers, 1 feeds the headpipe to another pisser, the 4th line feeds the stinger with a flow control valve set to open around 1/4 throttle. Setting it up like this enables the use of restrictors to fine tune your ski.

Can you share some pictures of your setup?

 

[fastgtfairlane]

Kinda hard to see the routing on my ski but I'll draw a diagram for you

 

[fastgtfairlane]

Quick diagram. I got the manifold from mcmaster. I have my manifold mounted in the bottom corner behind the headpipe. The 4 green lines are coming from the manifold. 2 feed the exhaust manifold to cool the engine, 1 feeds the bottom of the headpipe, the last line goes directly to the stinger with a flow control valve. The black lines are going overboard. 2 on top of the head and 1 out of the headpipe. I set it up this way for a few specific reasons. Cooler water directly from the pump helps regulate the headpipe temperature and I can install restrictors on each overboard line if I need more pressure somewhere else. No flow control on the headpipe keeps constant pressure on the headpipe water screws for better, more consistent spray pattern. All minor differences but all add up as well as adding more tunabililty to the exhaust.

 

[Reckless83]

So new pump shoe from ProWatercraft is a little to loose for my liking. I decided to add a few layers of carbon to close the gap up. We will see how she fits tomorrow after work.

 

[Reckless83]

Quick diagram. I got the manifold from mcmaster. I have my manifold mounted in the bottom corner behind the headpipe. The 4 green lines are coming from the manifold. 2 feed the exhaust manifold to cool the engine, 1 feeds the bottom of the headpipe, the last line goes directly to the stinger with a flow control valve. The black lines are going overboard. 2 on top of the head and 1 out of the headpipe. I set it up this way for a few specific reasons. Cooler water directly from the pump helps regulate the headpipe temperature and I can install restrictors on each overboard line if I need more pressure somewhere else. No flow control on the headpipe keeps constant pressure on the headpipe water screws for better, more consistent spray pattern. All minor differences but all add up as well as adding more tunabililty to the exhaust.

How hot does your pipe get, was thinking of building my own dry pipe?

 

[fastgtfairlane]

It really depends on how hard i run the engine. It doesn't get hot enough to sizzle but it's pretty warm maybe 100ish degrees after a wot run. I'm running a wet pipe and for freestyle freeride it's definitely better to run a wet pipe. You'll get better bottom end and throttle response especially down low with a wet pipe. I the top screw open around 1/2 turn and middle screw just cracked open. I have my cooling routing setup so I can add restrictors to any of the outlets to further control the temps. I live in the south so the water temps here reach into the 90s. Cooler water you can also add restrictors to control water temps

 

[Reckless83]

Pump shoe is in and setting up. Used 3M DP420 epoxy to install it.