Freestyle I have met my match = xscream [emoji853][emoji379]

Flash-FX

Flash-FX

No Square..No Round..FX-1
Location
South Jersey Shore
Like mentioned above, check for crankcase and head o-ring leaks. It's good to start with a properly "sealed" motor. Remove the head and check the O-Rings (they are probably chewed up). Make sure the domes don't sit flush with the head sealing surface. There should be a interference fit (the head is squeezing the domes on top of the cylinder liner) of approx .003"-.005"... What doe's the engine builder recommend? Also check the groove where the O-Ring seats. I've found that the viton O-Rings are a bit chubby and get squished out not allowing a metal to metal surface seal if not addressed. The groove most likely needs a touch of machining to get the O-Ring to set in the groove better.

As for the carbs, It's pretty much trial & error (jetting). But I have found that (because of the PFP headpipe), the jetting from the front carb will end up being different from the rear carb. The front cylinder will require a bigger size of jets than the rear. These motors generate high crankcase pressures that make it easy to run high pop-off #'s like 24-26 psi. BTW, check your reeds for good sealing as they can also give you a false rich condition when not tight against the stops.

How do I know this stuff?? I have a SS900 that was/is loaded with tuning "gremlins". With my carbs, (I have 3 different sets to experiment with) the low speed screw likes about 5/8 turn out from seated. If I try to open them out more, the motor will load up and it gets real muddy.
 
bach6177

bach6177

Flash-FX said:
Like mentioned above, check for crankcase and head o-ring leaks. It's good to start with a properly "sealed" motor. Remove the head and check the O-Rings (they are probably chewed up). Make sure the domes don't sit flush with the head sealing surface. There should be a interference fit (the head is squeezing the domes on top of the cylinder liner) of approx .003"-.005"... What doe's the engine builder recommend? Also check the groove where the O-Ring seats. I've found that the viton O-Rings are a bit chubby and get squished out not allowing a metal to metal surface seal if not addressed. The groove most likely needs a touch of machining to get the O-Ring to set in the groove better.

As for the carbs, It's pretty much trial & error (jetting). But I have found that (because of the PFP headpipe), the jetting from the front carb will end up being different from the rear carb. The front cylinder will require a bigger size of jets than the rear. These motors generate high crankcase pressures that make it easy to run high pop-off #'s like 24-26 psi. BTW, check your reeds for good sealing as they can also give you a false rich condition when not tight against the stops.

How do I know this stuff?? I have a SS900 that was/is loaded with tuning "gremlins". With my carbs, (I have 3 different sets to experiment with) the low speed screw likes about 5/8 turn out from seated. If I try to open them out more, the motor will load up and it gets real muddy.
Click to expand...

Lots of good info, thanks! The pump gas domes were just installed with a new oring kit. And I did notice what you said about the front cylinder running a little more lean than the rear. How much bigger did you have to go with your front carb jetting?


Sent from my iPhone using Tapatalk
 
mike b

mike b

Michael "Mayhem" Bevacqua aka MikeyChan
Location
California
bach6177 said:
The ski is my buddy’s, he actually had me remove the TL and go with charging because he doesn’t want to deal with the headaches.


Sent from my iPhone using Tapatalk
Click to expand...

Why do people claim that there are TL headaches? I understand for surf they don't like it but not Freshwater. I had my TL built nearly 3 years ago and I haven't done a thing to it. Best 300 dollars spent to have it built professionally. Running the right equipment is probably better than convenience. I would tell your buddy to get the proper bolt ons for that motor and his running issues might go away.
 
bach6177

bach6177

mike b said:
Why do people claim that there are TL headaches? I understand for surf they don't like it but not Freshwater. I had my TL built nearly 3 years ago and I haven't done a thing to it. Best 300 dollars spent to have it built professionally. Running the right equipment is probably better than convenience. I would tell your buddy to get the proper bolt ons for that motor and his running issues might go away.
Click to expand...

The main issue is he is not very mechanical and I don’t work on skis for people anymore as none of my skis ever get done. He wants somthing he can bar hop with and have power so TL isn’t really the choice for traveling miles from the house.


Sent from my iPhone using Tapatalk
 
Yami-Rider

Yami-Rider

TigerCraft FV-PRO
Location
Texoma
Pressure test with both manifolds installed, I dont care how "new" anything is, my xs was new with new manifold and it leaked.

That engine will never make very good power without a TL. If done right, they are more reliable then the MSD enhancer, I've seen tons of enhancer go bad. Depending on what battery you run, itll last all weekend. How hard is it to charge a battery lol.

Hopefully you get it figured out for Mark, but I think you probably have multiple things going wrong.
 
Flash-FX

Flash-FX

No Square..No Round..FX-1
Location
South Jersey Shore
bach6177 said:
Lots of good info, thanks! The pump gas domes were just installed with a new oring kit. And I did notice what you said about the front cylinder running a little more lean than the rear. How much bigger did you have to go with your front carb jetting?


Sent from my iPhone using Tapatalk
Click to expand...
The quick answer to your question is 5 points on the HS jet.... so far
Xscream recommended (as a starting point with 46mm Mikuni's) 117.5 H/S and 130 L/S jets. That would get you running, but (for me) the front cylinder would run too lean if you tried to ride 3/4 to full throttle for more than a few seconds. The rear cylinder runs almost perfect (1/2 turn out on the H/S and about 5/8 out on the L/S. The transition (1/4-1/3) is a bit rich, (as seen on a plug reading). I am up to a #125 H/S & 132.5 L/S in the front carburetor. I searched EVERYWHERE for info on tuning the PFP and all I found is how to make it wet for better low end and how to get pissed off when you find out the pipe has a internal crack and leaks. NOTHING about front to rear balance due to the exhaust manifold configuration (my guess). So, we are on our own with this.

(see attatched pic) I fitted a snowmobile dual EGT/ Tach to the manifold as a (mid to high speed) tuning aid. As none of this jet-ski stuff is close to perfect, It helps me to prevent another melted piston.

Be patient and start leaning things out a little at a time. Keep in mind that the cylinders run different from each other, but don't get crazy and melt stuff. Sparkplugs are cheap...
 

Attachments

  • IMG_3964.jpg
    IMG_3964.jpg
    158.6 KB · Views: 91
bach6177

bach6177

Flash-FX said:
The quick answer to your question is 5 points on the HS jet.... so far
Xscream recommended (as a starting point with 46mm Mikuni's) 117.5 H/S and 130 L/S jets. That would get you running, but (for me) the front cylinder would run too lean if you tried to ride 3/4 to full throttle for more than a few seconds. The rear cylinder runs almost perfect (1/2 turn out on the H/S and about 5/8 out on the L/S. The transition (1/4-1/3) is a bit rich, (as seen on a plug reading). I am up to a #125 H/S & 132.5 L/S in the front carburetor. I searched EVERYWHERE for info on tuning the PFP and all I found is how to make it wet for better low end and how to get pissed off when you find out the pipe has a internal crack and leaks. NOTHING about front to rear balance due to the exhaust manifold configuration (my guess). So, we are on our own with this.

(see attatched pic) I fitted a snowmobile dual EGT/ Tach to the manifold as a (mid to high speed) tuning aid. As none of this jet-ski stuff is close to perfect, It helps me to prevent another melted piston.

Be patient and start leaning things out a little at a time. Keep in mind that the cylinders run different from each other, but don't get crazy and melt stuff. Sparkplugs are cheap...
Click to expand...

Thank you for the info, I’m leak testing the motor tonight and going to try reverse jetting. I have been seeing the same with the front cylinder being much leaner than the rear.


Sent from my iPhone using Tapatalk
 
bach6177

bach6177

So this evening I leak checked the motor and found no leaks. Also I pulled the head and prints are good as well. Lots of oil tho. Then removed the carbs and check the reeds with my digital bore scope, All are seated properly.
9ce89ab7ca48e27af6da5f5c4614a216.jpg



Sent from my iPhone using Tapatalk
 
Flash-FX

Flash-FX

No Square..No Round..FX-1
Location
South Jersey Shore
Tested a set of Full Spectrum 48mm carbs (from 2006) on my SS900 yesterday. Once again the jetting is goofy. Your Novi's would probably (guessing) be similar in character.

1.8 N&S with black springs (25psi), 2 check valves, #60 return jet
Front carb 135 HS, 5/8 turn out. 127.5 LS, 5/8 turn out
Rear carb 132.5 HS 1/2 turn out. 125 LS, 5/8 turn out
Of course these 48's still need more fine tuning but are way more crisp/responsive than the Mikuni 46's. The overall jetting is closer in #'s because of the stronger signal the Full Spectrum carbs have vs the regular aftermarket Mikuni 46's.
 
bach6177

bach6177

Big Kahuna said:
I am curious to find out if cleaning this up corrected your jetting issues. I know there is more performance to be had there cleaning them up. skeptical that would cause your issues.
Click to expand...

It was causing enough turbulence to blow oil out of that cylinders new exhaust valve all over the motor.


Sent from my iPhone using Tapatalk
 
CARBONX2

CARBONX2

Location
South Africa
That step will dampen the exhaust pulse. You have your Novis the wrong way, pumps need to face out. What height are your filters? They look short in the pic, not enough flow area
 
bach6177

bach6177

Yami-Rider said:
That's how all those come, someone just bolted it straight on. Your losing some power, but doubt that fixes the issue(s).

I'd probably let PHP tune it too.
Click to expand...

Yeah PHP is taking care of it from here.


Sent from my iPhone using Tapatalk
 
You must log in or register to reply here.
Top Bottom