dual 46 tuning

[cookerq62]

What jets/pop off should I be running in dual 46's?

motor:
-83mm Ported 61x ports raised a bit and the sleeve on the intake side is notched
-ported 62t cases
-b-pipe limited
-rad valves
-stock timing (might do a slight static advance)
-low compression like 155lbs on a decent gauge
-prok's with prefilters
-gutted/modded squarenose hood

Right now the carbs have:
150 high
102.5 low
1.5n&s and a black spring

I'd like to keep the needle and seats if at all possible as they aren't cheap and I have a few 1.5 spares. With a single 44 I ran 122.5L 140 high 1.5N&s with a 115g. The motor ran way rich up top. I want something I can set and forget as far as jetting goes.
Thanx,
Ryan

edit:
110 main
117.5 piolt
2.0 ns
95g pop off


Thats what I am finding for dual 44's are 46's that much different?

 

[cookerq62]

bump

No one can get me in the ball park?

 

[Matt_E]

I would guess you'll need bigger jets in the 46's. Those dual 44 numbers you posted are ballpark - you'l' just have a lot of figuring it out to do.

Joys of tuning carbs.

 

[SUPERTUNE]

Carb settings I use are setup to suit my engine combinations. I try and use a set recipe for my engines so I can use what works on them everytime.

 

[waxhead]

i would be trying some thing like

130 low
110 high
and about 15psi pop off
if you want to stick with your 1.5 n/s i cant help you
you are trying to bring the fuel in to late with the higher pop off and its not going to work correctly

 

[Matt_E]

you are trying to bring the fuel in to late with the higher pop off and its not goign to work correctly

Depends on the setup - 25 psi on dual 44's works great for me, and I've tried from 15-32psi.
There are lots of ways to skin a Superjet.

 

[waxhead]

i always find if you are to high in the pope then the total sum of all your jetting to make it work is to much up top
you can get it right by using a smaller high
it just doent seem to hit down low like that
this is based on my findings only

 

[SkiDaddy]

Wax's setting have always worked great for me,:arms: :arms: :arms: except my porting (w/OEM 44s) wanted higher pop-off for crisper midrange. Try his suggestion.:cool2:

 

[Matt_E]

i always find if you are to high in the pope then the total sum of all your jetting to make it work is to much up top
you can get it right by using a smaller high
it just doent seem to hit down low like that
this is based on my findings only

I should add that with the lower and higher popoffs I tried, the rest of the jetting was appropriately compensated.
It hits best @ 25psi. (FOR ME)

 

[cookerq62]

I want to stick with the higher pop off also because I have had **** luck in the past trying to tune using low pop off's to my liking. It never seems to be consistent running a low pop off and power delivery is never as smooth as I'd like it. Is it pretty much standard to run a bigger low then high in duals? Also doubling up the check valves I'm guessing thats a standard thing? Anyone know what the stock jetting is in OEM 44's?
Thanx

 

[SkiDaddy]

Yeah, strongest, cleanest hit w/25 PSI here too.:arms: :arms: :arms: :arms:

Seems like it hit at a ~tad~ lower RPM w/lower popoff (but not as clean & strong), but w/pipe tuning it's now hitting almost off idle.

 

[cookerq62]

I ran it today Dual 46 wetjet carbs protec mani and rad valves.

110 high
130 low
29 psi pop off w a 1.5 n&s (watcon pump)

I have no clue what the screws are at as I can't reach em. It runs really well and doesn't load up and it's very clean. It rev's up so much quicker and its got boat loads more top end not so much more bottom then my single 44 but its very clean and crisp.

 

[#ZERO]

I have no clue what the screws are at as I can't reach em.

Get yourself a nice right angle carb adjusting tool and read this, http://www.mikuni.com/pdf/sbn_manual.pdf

There will be a quiz on Friday. :biggrin:

 

[Matt_E]

It should be required reading. :biggthumpup:

 

[cookerq62]

Who sells that tool I have been lookin everywhere. I thought watcon had em but i didn't see em on the site.

 

[#ZERO]

A lot of people make the right angle carb adjusting screw drivers.

One of the less expensive brands would be Motion Pro.

http://www.motionpro.com/motorcycle/tools/carburetor/