750sx Freestyle Build 1100cc

[roman]

Where in Michigan do you live? I am in Canton and ride at Whitmore lake. Sweet build by the way. Im always on the fence about pulling the 750 out and doing an 1100 in our 750sx. With that 148 pump yours will really pull!!

 

[Reckless83]

Where in Michigan do you live? I am in Canton and ride at Whitmore lake. Sweet build by the way. Im always on the fence about pulling the 750 out and doing an 1100 in our 750sx. With that 148 pump yours will really pull!!

I live in Three Rivers, MI. Still gotta weld two slugs on the pump to mount the intake grate. I was on the fence also but said what the hell. The 148 pump fits great with the Pro Watercraft shoe, just got some more work to do to get it 100%.

 

[roman]

If/When I do my triple swap, I plan on modifying the stock pipe like this. Dry it out, and remove the outer jacket.

 

[WFO Speedracer]

I am going to refer Quinc back to this thread when he says my 300SX -650SX bottom swap is too much work.

 

[Reckless83]

I am going to refer Quinc back to this thread when he says my 300SX -650SX bottom swap is too much work.

Not really work if you enjoy the build.

 

[WFO Speedracer]

Not really work if you enjoy the build.

I agree

 

[Reckless83]

Intake Grate Mount done, cut an old 750 pump up to steal the bracket from it. I did have to do some reshaping for the larger radius. I cut up a broken grate to use as the fixture for positioning.

 

[Reckless83]

So I have been busy wotking on making a hood mold so I can make a carbon fiber one. Got the plug almost done today.

 

[Reckless83]

Almost done with the mold, been taking a while as I'm trying to do as good of a job as possible to keep from having to do a bunch of work on it later.

 

[Quinc]

Not really work if you enjoy the build.

Everyone enjoys it in the beginning. It's that last 50hrs of work that gets ya! =) Making great progress though!

 

[Reckless83]

Everyone enjoys it in the beginning. It's that last 50hrs of work that gets ya! =) Making great progress though!

Yeah I got about 70 hrs in it so far lol.

 

[Reckless83]

Hood mold is almost done. Got some polishing to do. Looks soild to me.

 

[orangefinger]

curious , u left the pump tunnel and only modified to accept the 148 pump ? with the new threads/inserts u placed by aligning the shaft ? and then with pump shoe ?

will the pump be set back further ?

 

[Reckless83]

curious , u left the pump tunnel and only modified to accept the 148 pump ? with the new threads/inserts u placed by aligning the shaft ? and then with pump shoe ?

will the pump be set back further ?

Yes only modified the pump tunnel by filling the area when the shaft comes thru, replacing the pump shoe. I turned the 148mm pump down a little in the lathe to fit. I cut the intake grate bracket off the old pump and tig welded it on the new pump. I used the old intake grate as the fixture to weld it in place. Working on custom ride plate right now.

 

[kevbo]

You will probably get more cavitation at low speeds, it may be okay once your moving in smooth water. Just like a 550 with a 750 pump or an FX1 with a larger pump.

 

[Reckless83]

You will probably get more cavitation at low speeds, it may be okay once your moving in smooth water. Just like a 550 with a 750 pump or an FX1 with a larger pump.

I will play with prop sizing and find out what works best.

 

[kevbo]

Its mostly the inlet pressure drop at low speeds. The effect is trying to suck more water through a small straw. Water boils at atmospheric so we need as much inlet flow as possible.

 

[orangefinger]

just curious, why did u not cut the pump tunnel out of doner ski and just drop that in with the pump ?

Just looking at different options for an upcoming project

 

[Reckless83]

just curious, why did u not cut the pump tunnel out of doner ski and just drop that in with the pump ?

Just looking at different options for an upcoming project

I think cutting the pump tunnel out and swap it would make an area of weakness that would need repaired pretty often.

 

[Reckless83]

So it has been a while but have some updates to share. I have been working on making a custom pipe for this thing. Want to move it to the front of the motor to move weight around. Just got the flange I designed in the mail so I can keep going now. It will have a water jacket added to keep the heat manageable.