Carburetor (specs) Database: SuperJet and Blaster 1

Quinc

Buy a Superjet
Location
California
NO one with taper bored 38's here so I'll start this If anyone is still watching this thread? Does this sound too rich? Engine Jetmaniacs 718cc stage 2 ported engine with ADA 185 head. lightened flywheel, vforce reeds, R&D flame arrestors, TAPER bored group K 38's carbs, Msd enhancer, Riva red pipe.
LSJ 90
HSJ 150
pop-off 25
low screw 3/4
high screw 1 1/2
I figure I'll start here and go from there. ANy input? FYI the taper bore carbs are fuel hungry in my setup and required me to jet up to remove the hesitation.

That looks really rich. What does @JetManiac recommend?
 
Location
usa
unfortunately, since there are not alot of riders with the taper bores and my setup, neither group k or jetmaniac can reccommend settings. Jetmaniac did reccommend to go richer since the new motor will need more fuel than before. I was at 145 hsj before at 1 1/2. I was really hoping for at least one person with taper bores to put up their settings.. After I got the carbs back from group k, I had jetting adjusted by local shop who at least got it running but there was a low speed hesitation and would go into limp mode on wol. After reading every article on jetting out there, I started adjusting myself. It was running good at the end of last season.. at the previous settings and 145, but loaded up on idle, (lsscrew needed a little adjustment) Well, I guess better to start too rich than too lean.
 

cookn

Kamikaze
Location
where you live
@eastcoastx2
Main Jet : 145
Pilot Jet : 120
High speed screw : 1-2 turns out from closed
Low speed screw : 2 turns out from closed
Needle & Seat : Stock
Spring : 95 gram
these specs are from factory pipe website, so If i remember stock 61x jetting you are going up from 135 main and 115 pilot and changing the spring to 95gram
 
Location
minnesota
So I was looking on here and couldn't find exactly what I may need for a good starting point so if anyone has any ideas for me that would be awesome!

Just got a new motor and can't decide to run with the 38s it came with (like jet maniac suggested (I should probs go with his suggestion)) or tune the 44s I have.

So with 44s

B pipe
R and d intake
Ada head with 35's I think
Jet maniac 771 ported motor.
V force reeds
Solas mag 144
10/16 prop.

At 600-1100 ft alt.

Would like to add msd enhancer, lightened flywheel, bored reduction nozzle. If these would change jetting at all.
 

Mike W

Infidel
Location
North Florida
So I was looking on here and couldn't find exactly what I may need for a good starting point so if anyone has any ideas for me that would be awesome!

Just got a new motor and can't decide to run with the 38s it came with (like jet maniac suggested (I should probs go with his suggestion)) or tune the 44s I have.

So with 44s

B pipe
R and d intake
Ada head with 35's I think
Jet maniac 771 ported motor.
V force reeds
Solas mag 144
10/16 prop.

At 600-1100 ft alt.

Would like to add msd enhancer, lightened flywheel, bored reduction nozzle. If these would change jetting at all.

If you prefer plug and play, go with the 38s. My JM 735 was spot on with minimal tuning.
 
So I was looking on here and couldn't find exactly what I may need for a good starting point so if anyone has any ideas for me that would be awesome!

Just got a new motor and can't decide to run with the 38s it came with (like jet maniac suggested (I should probs go with his suggestion)) or tune the 44s I have.

So with 44s

B pipe
R and d intake
Ada head with 35's I think
Jet maniac 771 ported motor.
V force reeds
Solas mag 144
10/16 prop.

At 600-1100 ft alt.

Would like to add msd enhancer, lightened flywheel, bored reduction nozzle. If these would change jetting at all.

I have a 735 with similar setup, except with All the stuff you want to add and running a 9/15 hooker. Matt at HPE suggest this jetting and it was almost perfect except had to adjust low and high speed a little.

GP760 44's a good starting point is
115 pilot
125 mains
1.5 n/s
65 gram springs
1 1/2 high and low to start with.

Remember may need bigger main since a 771.
 
Location
israel
i just finished to jet my 44s and it runs perfect.
main jet- 100 (started with 120 and had to go down to 100)
pilot jet- 115
needle- 2.0
spring- 95gr
high needle- .75
low needle- 1.25
should have 25psi pop-off, tried few different springs to get it correct (all new 95gr springs read 22-27psi pop off)
i run the carbs with dual separate stock air boxes (leaves more room)
i have stock engine fresh bored to 82.5mm. i use the stock 760 intake with blocked cross-over.
ada head 37cc, msd enhancer, b-pipe, mag pump, 9\15 prop, vforce3, tbm light flywheel, rrp couplers.
 
Location
minnesota
Thrust just mailed me what I may need, I'll get everything in before this weekend hopefully. If all goes well I'll post what worked for me so others can get an idea too.
 

Mike W

Infidel
Location
North Florida
Just tuned my B1 and it's spot on.

Brand = Mikuni
Model = OEM
Size = 44
Quantity = 1
Main Jet = 140
Pilot Jet = 120
Needle/Seat = 2.0
Spring = 115
Pilot screw = 2
Main Screw = 2
- - - - - -
Gas Octane = 89 ethanol free
Altitude = sea level
Main type of riding = flat water
Would it pass the 10 second WOT test = sure
Powerband =
Motor type/setup = 61x/61x totally stock with Riva red pipe, stock f/a with three screens
 
Location
oakville
Brand = Mikuni
Model = Novi
Size = 48
Quantity = 2
Main Jet = 135
Pilot Jet = 147
Needle/Seat = 2.5
Spring = 65g
Pilot screw = 1
Main Screw = 3/4
- - - - - -
Gas Octane = 94
Main type of riding = Flatwater
Would it pass the 10 second WOT test = I think so
Motor type/setup = 910cc ADA 5mm stroker , novi 48, boyseen reeds/intake, powerfactor, msd enhancer
 
Changed my setup a bit. Still working on my jetting and I will post what I end up with when I'm done:
Brand = Mikuni
Model = Retail
Size = 46mm
Quantity = 1
Main Jet = 135
Pilot Jet = 125
Needle/Seat = 2.0
Spring = 115
Popoff = 28psi
Pilot screw = 7/8
Main Screw = 2
- - - - - -
Gas Octane = 93
Altitude = sea level
Main type of riding = freestyle/freeride
Would it pass the 10 second WOT test = Dont know. Not going to try.
Powerband = low/mid
Motor type/setup = 62T/61X (unported), ATP Intake, V Force 3 reeds, Stock F/A

Was this your final carb settings? If so, how was the throttle response on the bottom to mid?
Thanks,
Kevin
 

Mike W

Infidel
Location
North Florida
Was this your final carb settings? If so, how was the throttle response on the bottom to mid?
Thanks,
Kevin

Final for now. Throttle response is crisp all through the powerband. No hesitation at all when I nail it. Waiting to run a couple tanks to see what the piston wash looks like. But the plugs look good.
 
Location
oakville
Brand = Mikuni
Model = Novi
Size = 48
Quantity = 2
Main Jet = 135
Pilot Jet = 147
Needle/Seat = 2.5
Spring = 65g
Pilot screw = 1
Main Screw = 3/4
- - - - - -
Gas Octane = 94
Main type of riding = Flatwater
Would it pass the 10 second WOT test = I think so
Motor type/setup = 910cc ADA 5mm stroker , novi 48, boyseen reeds/intake, powerfactor, msd enhancer

@andreo420
 
Picked up my first ski, starts up and runs but not making power above 5/8 to 3/4 throttle, had it out today after reading all 17 pages trying to tune it but didn't have much luck. I tried pilot screw 7/8 to 1 1/4 and main screw 1 1/4 all the way to 2.5 out and everything in between with not much change. seems to be running lean i tried a plug chop at 2 out on the main and all white ceramic.

Current mods are:

Dual 38's prok F/A's
High comp head 35cc domes
Port matched coffman sizzler/TDR waterbox
Jetski solutions coil with msd boots
Dual cooling

Current carb specs:
Brand= Mikuni
Model= OEM
Size= 38
Quantity= 2
Main Jet= 135
Pilot Jet= 70
Needle/Seat= 1.5
Spring= 95
Pilot Screw= 7/8
Main Screw= 1 1/4

running 92 octane 40:1 castor 927. 500-800 above sea level. Looking for low to mid end power I was going to order a rebuild kit with new mains and needle/seat, any suggestions would be greatly appreciated
 
Need assistance:
Been trying to tune my single 44 but can't get that perfect sweet spot.
61x ported cylinders
Freshly bored to 82mm
Stock x cases
PSI pipe
ADA head 35cc domes
Stubby cone
Bored nozzle to 86mm
Solas 13/17 prop
Riva cone F/A
Stock ignition

Carb specs:
Brand = Mikuni
Size = 44
Quantity = 1
Main Jet = 150
Pilot Jet = 125
N/S = 1.5
Spring = 65g (tried 95g also)
Pilot Screw = 1.5
Main Screw = 1.5

Currently running 32:1 93 octane since I'm still breaking the bore in. Usually run 50:1. Looking for that low end grunt. Freestyle rider of course! Plugs are usually black and wet and I'm always running overly rich. What would the desired popoff be and should I be using 2.0 or 2.3 N/S? Any advice would go a long way! Thanks.


Sent from my iPhone using Tapatalk
 

Quinc

Buy a Superjet
Location
California
try a 2.0 seat 95g spring and 155 main jet.

mikuni_pop_off_pressure_chart.jpg
 
try a 2.0 seat 95g spring and 155 main jet.

mikuni_pop_off_pressure_chart.jpg

What would an ideal popoff be for my setup? And what is the best way to adjust high and low screws? Seems like there are many ways to go about it. Mikuni says to dial in the idle screw till a steady idle then turn low speed 1/4 in or out till engine rpm rises. Tried that yesterday but couldn't find that spot where rpm increased.


Sent from my iPhone using Tapatalk
 
Top Bottom