Dual SBN38 Carb Adjustments For Modified Superjet

[METALMULISHA559]

Hey guys, I searched for a while but could not find the answer so sorry in advance if this has been answered already.

I have a 95 Superjet with a stock bore 701 62T/61X SBT motor. My list of upgrades is shown below. I have just installed VForce 2's and rebuilt my carbs including new needle and seats, and re-jetted for the B-Pipe. My carb adjustments were about 1 7/8 on top and 2 on bottom, give or take 1/4 turn between the two carbs. The ski ran almost flawlessly with those settings but since i've changed the carb springs and jets, I am wondering what carb adjustment settings I should start at when I take it to the lake this weekend to fine tune it the rest of the way?

Current Build List:

• Stock bore 701 62T/61x SBT motor
• ADA girdled head with 35cc domes
• VForce 2 Reeds
• Lightened flywheel
• Factory B Pipe - Limited
• MSD Coil
• MSD CDI
• 9/15 Hooker Impeller
• 144mm 12 vein Solas mag pump
• TDR waterbox

 

[Quinc]

70/135 stock pop off.

 

[METALMULISHA559]

70/135 stock pop off.

I got that part done already. All I'm wondering is where should I set my high and low speed adjustment screws for a good starting point when tuning the ski? My specs are listed in my listing above.

 

[MTRHEAD]

I assume you own a tach?

 

[JetManiac]

What is sizes and popoff of your jetting?

 

[METALMULISHA559]

I assume you own a tach?

I do not lol

 

[METALMULISHA559]

What is sizes and popoff of your jetting?

I just got em from you. 70/135 95g spring.

 

[Big Kahuna]

Carburetor (specs) Database: SuperJet and Blaster 1

The SuperJet and B1 Carburetor Database I'm in the process of putting a pair of 46mm Mikuni's on my SJ to see if I like them and have been thinking of how I plan to jet them. I then though how helpful it would be if we all had a large database list of what others run with their given setup...

www.x-h2o.com

 

[Quinc]

I got that part done already. All I'm wondering is where should I set my high and low speed adjustment screws for a good starting point when tuning the ski? My specs are listed in my listing above.

No one can tell you that, and it changes based on elevation and air temps. You need to adjust the screws until you find what is best.

 

[kevbo]

Set the bottom screw out of the water, just close it until the engine races and open it until it slows down, no telling where it will end up. The top screw supplements the main jet so open it until full throttle power reduces and then close just until it peaks. You want to be a little rich of peak power.

 

[METALMULISHA559]

Set the bottom screw out of the water, just close it until the engine races and open it until it slows down, no telling where it will end up. The top screw supplements the main jet so open it until full throttle power reduces and then close just until it peaks. You want to be a little rich of peak power.

Thanks, IL give that a shot. Prior to the rebuild I had an issue with it wanting to death Rev out of water so I'm still a little scared that may happen again so Idk how I feel about setting the bottom screw adjustments out of water. Maybe I'll do that on the trailer at the lake so I can dip it in if it starts to run away lol

 

[METALMULISHA559]

Thanks, IL give that a shot. Prior to the rebuild I had an issue with it wanting to death Rev out of water so I'm still a little scared that may happen again so Idk how I feel about setting the bottom screw adjustments out of water. Maybe I'll do that on the trailer at the lake so I can dip it in if it starts to run away lol

Thanks, IL give that a shot. Prior to the rebuild I had an issue with it wanting to death Rev out of water so I'm still a little scared that may happen again so Idk how I feel about setting the bottom screw adjustments out of water. Maybe I'll do that on the trailer at the lake so I can dip it in if it starts to run away lol

I also replaced the needle and seat which were clearly worn so maybe that will fix the death Rev issue

 

[kevbo]

If it starts dieseling at idle just go full throttle and pull the lanyard. You can also hit the primer, either way it will stop running. The idle adjustment is super easy to set out of the water.