2004 Sportster with 2006 GSXR 750 motor installed

[CollinCountyCab]

A month ago we picked up a 2004 Sportster that the "owner" says to me make sure you want this and look it over before we exchange cash for title. No worries....it was so "cheap" i didn't even think it had a motor in it! We take off the cover, open that hatch and holy &^%% this is what I saw.
Since I've updated the drive line to older carrier bearing, realigned motor, installed new stator and rectifier, changed oil, plugs and air filter. Cleanded carbs, upgraded some wiring to 10 gauge and relocated rectifier. The builder had the rectifier on the "firewall inside engine compartment. NO GOOD!! Didn't get any air to cool off so they burnt up 2 of em.... Had a bad cavitation problem but solved that with getting rid of carbon ring and resealing pump with new wear ring. I need to get a different impleller so I have instant hookup. Right now there is no forward thrust until boat revs to 4k RPM. Stock impeller currently installed. Anyone in the north Dallas area wanna come check it out or hit the H2O, email me!
Here are some photos.

[CollinCountyCab]

More photos...

[BUDDAH@PPG]

WOW!!!!!!!!!!!!!!!!!!!! Someone did thier homework on this one.

First time I have ever seen a relatively clean frankenstien install.

Just don't go reaching in that engine compartment when those chains are spinning or you could lose something.

[CollinCountyCab]

It's amazing what they did for sure. Runs good, just need the right impeller pitch.

[BUDDAH@PPG]

What pitch/style inpeller in there now?

What is the operating RPM range?

What would be the peak RPM at W.O.T would you like to see but not exceed?

Be glad to help get you dialed in, just need some info to better advise.

[CollinCountyCab]

What pitch/style inpeller in there now?

What is the operating RPM range?

What would be the peak RPM at W.O.T would you like to see but not exceed?

Be glad to help get you dialed in, just need some info to better advise.

The stock impeller is still installed.
RPM now goes up to 14k.....yes...14000!
Peak is not important "to me"....I'm not looking to go 100mph. I would love to throttle and it do a wheelie....stand it straight up in the air. I think that would be cool as long as i could ease the throttle and get up to maybe 45 or 50mph. I would much rather have a bunch of low end torque.

[BUDDAH@PPG]

ok. Let me see what I can do.

This will indeed be a custom prop, but I will sure try my hardest to get you what you need.

Get back to you (probably) next week as it is Friday already.

I'll do everything I can.

[CollinCountyCab]

Need to figure out how to make this boat move instantly.....it takes like 3500 RPM for it to move forward and 5000 RPM for reverse. What pitch should i go with. I would rather have low end than go 80mph. thanks

[BUDDAH@PPG]

are you cavitating out of the hole?

I see the new wear ring installed, just seems a little strange that you are getting no thrust till you reach such a high RPM.

[CollinCountyCab]

New wear ring, aligned motor and installed carrier bearing. I dont know if it's cavitation or not....I just know it takes a bunch of RPM to move.

[BUDDAH@PPG]

OK...
What is your idle RPM and at what RPM would you say you will most likely be operating in?

We already know you peal RPM is 14k.

Just need the following information so I can make a call for you about a proper impeller for your application.

[CollinCountyCab]

It idles at like 800 and i would like to be able to access up to 10k. Cruising around 8K??

[BUDDAH@PPG]

Got it.

Let me see what I can find for you.

Post back a little later today.

[CollinCountyCab]

Any new info on impeller as I want to order it!!

[BUDDAH@PPG]

I have done a bunch of digging and made a few calls to the prop manufacturers and you have 1 very big obstacle to over come.
The gear box wil change ALL of the specs on the prop depending on what gear you are in.

These machines are direct drive from the manufacturer with no gear box.

That being said.... There simply isn't a (proper) prop to outfit you with.
You are at the trial and error section of this project.

I will keep digging in hopes of finding something to fit your needs.