Starting point jetting, Kaw 750/B pipe, sxr carbs

[Crab]

Just trying to get close with a ported Kaw750, B pipe limited chamber, SXR duals with balance tube, stock airbox, no chokes. And perhaps a guess with the balance tube pluged.

 

[D Slicker]

Crab, Look on the factory page and go up one size on each with the chokes out. That should be a good start. I am leaving the wet pipe jetting in mine with the coffman. Paul sent me jet I will look at what size they are. He sent them for when I take my chokes out.

 

[Crab]

Crab, Look on the factory page and go up one size on each with the chokes out. That should be a good start. I am leaving the wet pipe jetting in mine with the coffman. Paul sent me jet I will look at what size they are. He sent them for when I take my chokes out.

Thanks, let me know. Should finish up reinforcement tonight with pictures.

 

[D Slicker]

Crab, with the choke plates in its 152.5 main and 80 pilot.

 

[Crab]

Crab, with the choke plates in its 152.5 main and 80 pilot.

Slicker, do you remember when you had the SXR pipe, did the exhaust manifold resemble the 650 manifold for the 3 hole indexing, or was it rotated clockwise about 20 degrees?

 

[D Slicker]

Its the one in you hand.

 

[Crab]

Actually i think it was Wax's hand. Ok, im going with SXR exhaust manifold, headpipe, and B limited chamber.:Banane01: :Banane01: :Banane01: :Banane01: :Banane01: :Banane01: :Banane01: :Banane01: :Banane01: :woot:

 

[Scorn800]

With the chokes removed I'm running 155 mains & 80 pilots on a dry pipe and plan to run the same on my wet pipe.
What chamber you go run? I plan to try the sxr wet pipe chamber, a 750 limited, & possibly a 750 mod.

 

[Crab]

With the chokes removed I'm running 155 mains & 80 pilots on a dry pipe and plan to run the same on my wet pipe.
What chamber you go run? I plan to try the sxr wet pipe chamber, a 750 limited, & possibly a 750 mod.

B pipe limited in an X2.

 

[Scorn800]

You mean a yami sj limited or a kawi?

 

[Crab]

You mean a yami sj limited or a kawi?

Yami chamber in the X2, 800 wet pipe won't fit.

 

[ROTATION]

80p
150m
38psi
Cross-over tube filled and chokes still in

 

[Crab]

I just checked mine, they are stock jetting. Anyone know the stock turns out on that carb?

 

[ohell]

stock turns on that carb - my tiny brain got lost... but if you are referring to stock sxr carbs sbn-40-38 stock jetting of 72.5 LS, 132.5 HS, 1.5 N/S 80g spring, approx 38psi PO
LS Needle @ 7/8 turn HS Needle @ 3/4 turn

if you get running soon, i'd appreciate sharing results. i'll do same in this thread, but slow build because my damn XP build is dragging. gonna get together similar set up - 750 bored to 83mm, ported, b-pipe, jet world bored sxr carbs w/ stock air box. gonna try blocked passage first on stock intake, if i don't get what i'm looking for swap to open intake. if that doesn't work might go with 44's or switch up exhaust.

 

[Crab]

stock turns on that carb - my tiny brain got lost... but if you are referring to stock sxr carbs sbn-40-38 stock jetting of 72.5 LS, 132.5 HS, 1.5 N/S 80g spring, approx 38psi PO
LS Needle @ 7/8 turn HS Needle @ 3/4 turn

if you get running soon, i'd appreciate sharing results. i'll do same in this thread, but slow build because my damn XP build is dragging. gonna get together similar set up - 750 bored to 83mm, ported, b-pipe, jet world bored sxr carbs w/ stock air box. gonna try blocked passage first on stock intake, if i don't get what i'm looking for swap to open intake. if that doesn't work might go with 44's or switch up exhaust.

You must be thinking sxi, my stock sxr carbs have the 152.5 high speed jet, 80 low. Not sure on the N/S and popoff, what ever stock is. I plugged off the crossover and cleaned up the ports a little, tonight I pulled the chokes and was going to install my primer kit. The fittings Zig sold me fit, but are the same size as the shafts, and will need to be JB welded in. I'm going with the recomendations for a SXR wet pipe jetting for now, and see where that gets me. I figure, richer from the pipe probably cancels out the need for jetting down for no crossover and improved carb signal.

 

[ohell]

nope, that was stock sxr carb set up. 72.5/132.5, 1.5 N/S, 80g, 7/8 turn LS, 3/4 turn HS

your stock carbs came jetted for 800 b-pipe 80/152.5, stock N/S, 1 turn LS, 1/2 turn H/S

 

[lextoy]

doh, now i find original jetting specs for my sxr carbs... who knows what 1 jet size equates too, like as in turns on the screw vs. a new jet.
lets say 67.5 vs. 72.5...
could you turn the screws out on a 67.5 to get 72.5?? or even bigger????
i know you try to tune so screws are always around 1 turn out, but what does 1 turn actually equate to on a 67.5??? 68.5? 70? 72.5?
hmmmmm

 

[Crab]

I ended up at 75L, 145 H, 33 psi, 1.5ns.

 

[lextoy]

ok i think i found it.
1 turn is equal to about 2.5 on a jet
so a
67.5 at 1 turn out = 70
67.5 at 2 turn out = 72.5
67.5 at 3 turn out = 75

if you have to go more than 2 turns its better to go up a jet size and start over

 

[lextoy]

crab, your crossover on the carb manifold(balance tube) is filled right? that would mean if it wanst filled, i would need slightly larger jets, cuz of less air vaccum (signal) on each carb.
chokes are out? same as mine.
how many turns out are you on the LS and HS??