650SX/X2 build

[Vumad]

So, Tom, #.0 and I have been discussing the power of the X2. We all think it sucks, even though mine is tuned out great.

We've come to the following conclusions...

The pipe and waterbox hold too much water and it backs up the exhaust on the bottom end. The 650 pipe is very restrictive because of it's smaller diameter. The ski is also underpropped, and the electronics could use some advancing.

I rode shawn's ski, it has WAY more torque than mine. Similar set ups...

I have 44 mikuni, shawn has 46 mikuni
i have westcoastpipe , shawn has coffman's pipe
I have 750 electronics stock, shawn has 650 electronics advanced
I have nameless aftermarket waterbox, shawn has stock waterbox

The power in the mid and the high is the same, but for bottom end torque, Shawn's ski destroy's mine. I need to figure out how to get that power. I'm going to avoid the 650 electronics, even thought it has a lighter flywheel. I hear there is a timing advancement plate for the 750 that I will be looking into.

I also picked up a factory B-pipe. I have kawi manifold, head pipe and kawi 750 limited chamber. It's not perfect, but it's pretty dang clean. I wasn't going to buy a B-pipe, but for $175 and a hour drive round trip... I had to spend the money and let my 750 breathe.

The Factory Pipe Limited system will add 20+ horsepower, 850 rpm, and 6 mph to your stock SX/SXi using no other performance parts except a K&N flame arrestor and different carb jets. The 750SX/SXi Limited system includes our tunable headpipe, stainless center bleed chamber, tuned exhaust manifold and all required installation hardware. ECWI® recommended for the best acceleration.

 

[Vumad]

I also found a company called Exactal Tool in new jersey that will recondition my pump. The deal is like this...

I mail my pump to Scott (approx $20)
Scott replaces the pump liner and etc, then ships it back to me ($150)
Scott will place new bearings in my pump upon request (additional $20)

This is what I have understood from e-mails and voice mails. I don't have the extra $200 right now, so I haven't had the work done, but I intend to speak to scott and have the work done. I have a nice 10/18 prop to put on my ski but the old liner will destroy the prop and I just can't have that.

SBT will not recondition Kawi pumps. They will recondition yamaha pumps however.

Edit: I say 10/18, but it might be 9/17. I'm not sure... It's not hugely important.

 

[x2skier]

Vumad, Have you tried to mock up the Factory Limited exhaust yet? I plan on installing one on the X2 I'm building (http://www.x-h2o.com/threads/29480) as soon as I find one for the right price. Good score on your part for $175 plus a little driving.

There was a guy on pwctoday who was having trouble installing one on his X2. Apparently, the indexing of the Factory manifold throws the head pipe into the hull (causing it not to seat flat) and the stock or WC manifold indexing doesn't allow the chamber to line up properly.

I just picked up a Factory Mod setup for my Blaster but going to try it on my X2 first. The Yamaha head pipe is about 10mm shorter than Kawi head pipe, which might be enough to allow it to sit properly. I should have it early next week and will post up the results.

 

[Vumad]

I haven't tried it yet. I am not installing the B-pipe on my X2 yet. I finally got it running and I want to enjoy it for a bit before I take it apart again.

I do have some concerns about the pipe fitting... I was nervous about buying it but someone pointed out to me that I could defenitly get my money back out of it if it doesn't work out.

I don't know why it wouldn't work. Pete is running the B-pipe in both of his X2's. The only difference should be the chamber. I figured everything would fit if it clears the hood.

 

[Crab]

I'm wanting to try my Blaster limited chamber with no other changes to compare with the SJ limited, when I pull the tank for sponsons I may just do that.

 

[x2skier]

I haven't tried it yet. I am not installing the B-pipe on my X2 yet. I finally got it running and I want to enjoy it for a bit before I take it apart again.

I do have some concerns about the pipe fitting... I was nervous about buying it but someone pointed out to me that I could defenitly get my money back out of it if it doesn't work out.

I don't know why it wouldn't work. Pete is running the B-pipe in both of his X2's. The only difference should be the chamber. I figured everything would fit if it clears the hood.

You're right the B Pipe fits and works well with the SJ and Blaster limited chambers. I have yet to see a center bleed style chamber (Kawi limited or Blaster Mod) on an X2. There's a picture floating around with a Kawi Mod pipe in an X2, which is similar to the Limited but with an end stinger exit instead of the center bleed.
I'm hoping I can get the Blaster Mod pipe to fit mine.....might take a little cutting and welding though.
Good luck with yours and keep us updated when you try it.

 

[Vumad]

Some stuff happened today...

Pic 1 - last time I took my ski out... my bilge was pumping on shore. I left the ski in the water and could actually see water comming in arround the bearing housing area at a good rate. Today I pulled the engine compartment and here's the housing. I will be getting a new setup from SBT.

Pics 2-4 - While I had the engine out... I took a look at how the B-pipe will fit into the hull. The B-pipe will not fit into the X2 hull with a factory manifold. Tom and I do think it will fit in with a modified westcoast or stock manifold. The westcoast has a mounting spot on the manifold that interfeared with the alignment of the Kawi limited chamber, but we believe that if this mounting part is ground off, everything will fit. The kawi limited chamber should fit in with the stock fuel tank. It appears to have the clearance. However... I will have to make a custom mounting bracket for the chamber, because the mounting bracket provided with the limited chamber would force the chamber to align with the front of the cylinder, and that just aint gonna happen.

Pic 5 - So... interesting story... I was just cleaning up the garage a bit to try to maximize what little working space I had. Well, as I was cleaning I was tidying my box of manifolds and etc, and I happened accross on of my keihin carbs. I thought to myself, what a strange keihin, the fuel pump is on the wrong side. Is this a Mikuni? Sure enough... it is!!!!!! A 44mm mikuni none-the-less!! The means I now have a matching set up 44mm mikuni carbs to put on my X2. This carb is rough, and will surely need a rebuild, and I'll have to find a throttle linkage, but in any case... being able to go to a dual 44mm set up on my X2 is great! especially once I get my B-pipe set up.

 

[Vumad]

I wish I would have took a picture of the gasket before I pulled it off the carb. The person who installed the gasket installed a stock gasket and didn't trim it. The gasket was blocking at least 4mm of airflow. :trink26:

 

[Crab]

That should be opened up to at least 46mm, and I have a PJS dual 44 manifold if needed.

 

[special fx]

I'll give ya $20 for your torn bearing housing......don't throw it away!

 

[Vumad]

That should be opened up to at least 46mm, and I have a PJS dual 44 manifold if needed.

I just have the stock manifold. I was going to bore that open if I could. That would be cheaper than buying something else. PM me with a price and I'll consider it.

 

[Vumad]

My X2 is out of comission awaiting a brand new bearing housing and a recondissioned pump.

Today I was sitting bored and it struck me... My 650SX is rotting in the back yard, with a perfectly good driveline in it (which I hadn't removed because it's awaiting it's 650 motor install). Well... it was sititng in a pile of parts, and w/in 3 hours, I completely had everything reinstalled (some of it was half assed I admit... I have been learning how to get a ski on the water FAST from WaveDeamon. He's the mastah.) and I was on my way to the water.

Anyway, the ski ripped...

and the lesson learned today...

The waterbox in my X2 SUCKS. The only difference b/t my X2 and my SX is the waterbox and the prop (15.5 instead of 14). The stock SX waterbox made a huge difference in cleaning up the bottom end. Same pipe and everything... it also didn't sound like a nitro car anymore. It's got a great throaty sound to it now. I love it.

 

[Vumad]

BTW, The SX waterbox doesn't fit in the X2. It's too wide. I'd like to get another waterbox for it. I think stock will work just fine for me... as long as it's pretty light. I had something I thought was a X2 waterbox but it weighs as much as a brick so there's no way I'm using it. I showed it to Tom and he doesn't think it is stock.

 

[tom21]

a few posts back you were fighting cavitation- seems worth it to mention now that you found the bearing carrier was split and letting in water which was inversely sucking air into the pump.

if you would like we can cut open a stock waterbox to see how its setup and then fix those other piles of junk or just modify the sx one to fit. or make a smaller one to make more room and lighten things up front?

um sorry pal- sunday was the smallest day and I didn't see you 15' in the air- may have felt like 15. more like 5. :dunce:

 

[Vumad]

a few posts back you were fighting cavitation- seems worth it to mention now that you found the bearing carrier was split and letting in water which was inversely sucking air into the pump.

if you would like we can cut open a stock waterbox to see how its setup and then fix those other piles of junk or just modify the sx one to fit. or make a smaller one to make more room and lighten things up front?

um sorry pal- sunday was the smallest day and I didn't see you 15' in the air- may have felt like 15. more like 5. :dunce:

Sunday was the largest day. The waves were head high at 3pm when the storm rolled in and it started raining.

I don't want to modify my SX waterboc. I will need it to go back into the SX when I put my 650 engine back together. I'll probably just buy a waterbox for the X2.

 

[inchadeboca]

vumad, what r u gonna be doing with the Xi hull ??

 

[Vumad]

It's being stripped down to the bare hull. The bare hull will be sold with title.

 

[inchadeboca]

what r u lookin to get for it ?

 

[Vumad]

Well, I took my state test for EMT. I passed. I'm now Nationally registered and a state certified Emergency Medical Technition. I'll be able to start applying to jobs to drive an ambulance in 2-3weeks when all the paperwork is sorted out.

Meanwhile, I now have the free time to get back to work.

There was an open discussion about what I would be doing to my ski here ---> http://x-h2o.com/showthread.php?t=31357 and now it's time to make those things happen.

I'm not 100% sure on how I'm going to go about all of this. I am considering leaving my current hull exactly as is, and building up the engine now. I can ride the ski while I take the time to fix up another hull with some paint and shaved hood and hull and bottom mod and all that good stuff.

I've been riding a 650SX with my 750 engine in it. I enjoy the 650 quite a bit but I'd rather get that engine back in the X2 as quickly as possible. I just enjoy the X2 that much more. Using a different hull will let me get all of those crazy mods done while still riding a X2.

So here we go... back on track.

Pic 1 is the spare hull as it was when I got it out of the yard tonight.
Pic 2 is after I stripped all of the parts out of it and cleaned it up with the hose.

It's pretty dark, so you can't really tell, but it's in significantly better shape in the latter picture.

 

[Vumad]

I was being lazy and Tom Sawyered it. The neighbor kids were trying to strip the gel coat off of that ski.

I was going to use this ski, I thought it would have been just as easy as using the other one, but it has 4 layers of gel coat on it. It usually takes 2 hours to strip off the gel coat. This hull would take a week. I'm not going to use it (for this project, have another in mind for it still but that will be later).

Yes Tom, I know, I wasted my time.