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hooligan
05-09-2005, 11:58 PM
I've fitted '91 gsxr 750 (38mm)carbs to my '87 gsxr 1100, and having trouble with jet sizes. I bought a factory pro kit, the smallest was a 147.5, and it fouls the plugs after about 2hrs ride time.
The engine is bored to 1127, full stainless micron system & shortened race can and K & N pod filters. Any ideas? Mundy?

06-09-2005, 10:50 PM
i'm not sure about factory pro kits,but dynojet recomend ideal jet for 1127 (with 36's) r 130-135 depending on where ya want the power.dont think they gave specs for 38's except for 750. they make venturi jets which give the right delivery where ya need it without sacrifising either midrange or top end,therefore not fouling plugs.i'm no expert here mate,but i visited their site coz i'm fittin up BCM twin pods shortly , have been told to leave the air box on an get a single K+N but fuck ya gotta try these things ay.pretty sure Mad had fouling probs with 150's then dropped to 135's but i'll let him confirm that for ya.my pods came with factory pro jetting guidelines that said to e-mail them direct if ya havin probs.
anyhow heres the specsfor 1127 with 38's for factory pro and pipe.

pilot jet #32.5
needle #0985h-64t2
needle clip : #2 position
fuel level :15mm (tilt carbs,measure from gasket surface to to of float)could be the problem.
Main jet :#152.5 (with pipe option #145 to #155)
MJ supplied should be 152.5+155.
fuel screws :3 turns out.set to 3% to 5% CO if using exhuast gas analyzer.
slide holes : plug 1 hole with epoxy..option B:drill plugged hole to 1.5mm dia. could also be problem.

if you dont already have it,i've got tuning guidelines for this set up.e-mail me if ya want me to send ya copies.

i will also draw a picture of a Dyno and throw that in, makes life easy when tuning.:D

06-09-2005, 10:50 PM
i'm not sure about factory pro kits,but dynojet recomend ideal jet for 1127 (with 36's) r 130-135 depending on where ya want the power.dont think they gave specs for 38's except for 750. they make venturi jets which give the right delivery where ya need it without sacrifising either midrange or top end,therefore not fouling plugs.i'm no expert here mate,but i visited their site coz i'm fittin up BCM twin pods shortly , have been told to leave the air box on an get a single K+N but fuck ya gotta try these things ay.pretty sure Mad had fouling probs with 150's then dropped to 135's but i'll let him confirm that for ya.my pods came with factory pro jetting guidelines that said to e-mail them direct if ya havin probs.
anyhow heres the specsfor 1127 with 38's for factory pro and pipe.

pilot jet #32.5
needle #0985h-64t2
needle clip : #2 position
fuel level :15mm (tilt carbs,measure from gasket surface to to of float)could be the problem.
Main jet :#152.5 (with pipe option #145 to #155)
MJ supplied should be 152.5+155.
fuel screws :3 turns out.set to 3% to 5% CO if using exhuast gas analyzer.
slide holes : plug 1 hole with epoxy..option B:drill plugged hole to 1.5mm dia. could also be problem.

if you dont already have it,i've got tuning guidelines for this set up.e-mail me if ya want me to send ya copies.

i will also draw a picture of a Dyno and throw that in, makes life easy when tuning.:D

11GSX
06-09-2005, 11:05 PM
Hey hooligan, ive got the same setup in my 86 1100, 91 750 38's with a factory pro jet kit, not sure what size jets they are but ill have a peek in the box tomorrow to see. alternatively give startline racing a buzz at springwood, they set mine up! they just might be able to tell u over the phone!

11GSX
06-09-2005, 11:05 PM
Hey hooligan, ive got the same setup in my 86 1100, 91 750 38's with a factory pro jet kit, not sure what size jets they are but ill have a peek in the box tomorrow to see. alternatively give startline racing a buzz at springwood, they set mine up! they just might be able to tell u over the phone!

11GSX
07-09-2005, 02:45 PM
just checked whats left in my factory pro jet kit, i have smaller jet sizes than 147.5 left in my kit, still not sure what size they fitted tho...maybe u have been given the wrong kit? check it out anyway.

11GSX
07-09-2005, 02:45 PM
just checked whats left in my factory pro jet kit, i have smaller jet sizes than 147.5 left in my kit, still not sure what size they fitted tho...maybe u have been given the wrong kit? check it out anyway.

07-09-2005, 09:17 PM
YUP! try DYNA JET jets at about #130 with standard needles 1 richer

07-09-2005, 09:17 PM
YUP! try DYNA JET jets at about #130 with standard needles 1 richer

hooligan
08-09-2005, 12:47 AM
Thanks guys. The kit came with 150 & 147.5's I've got a set of 130's from the original 34mms.
Mundy, ya reckon they might be better?

hooligan
08-09-2005, 12:47 AM
Thanks guys. The kit came with 150 & 147.5's I've got a set of 130's from the original 34mms.
Mundy, ya reckon they might be better?

11GSX
08-09-2005, 01:45 PM
While your at it u might wanna check the emulsion tubes and needles as they seem to get a bit of wear in em, the reason i went for factory pro kit was that the emulsion tubes came in the kit and the dyna jet kit didnt.

11GSX
08-09-2005, 01:45 PM
While your at it u might wanna check the emulsion tubes and needles as they seem to get a bit of wear in em, the reason i went for factory pro kit was that the emulsion tubes came in the kit and the dyna jet kit didnt.

09-09-2005, 09:49 PM
this is mine,36mm slingas off 88/750.
42.5 pilot.
slides drilled to 2.8mm.
needles at 1 richer.
reduce spring hieght 5mm. from std.
mains at 127.5.
std.float(do not fuck)
3 turns out or 2.5 on fuel jiga
K&N pods,1 for each carb.
HEAT SHIELD in front of bank to stop engine heat.

09-09-2005, 09:49 PM
this is mine,36mm slingas off 88/750.
42.5 pilot.
slides drilled to 2.8mm.
needles at 1 richer.
reduce spring hieght 5mm. from std.
mains at 127.5.
std.float(do not fuck)
3 turns out or 2.5 on fuel jiga
K&N pods,1 for each carb.
HEAT SHIELD in front of bank to stop engine heat.

hooligan
05-10-2005, 05:22 PM
Fixed. 135 mains and needles from a 96 gsxr 750.

hooligan
05-10-2005, 05:22 PM
Fixed. 135 mains and needles from a 96 gsxr 750.

05-10-2005, 08:33 PM
;)

05-10-2005, 08:33 PM
;)

spoonman
29-03-2006, 01:56 PM
i fitted my 89 1100, 36ss carbs, with k&n pods...now i have to find a jet kit! i have done a little homework with the dyno-jet stage 3 kits. Firstly the Dynojet kit part #3136 is listed for my bike on dynojet.com, but after i emailed them they directed me to serco.com.au and they have got part #3127 listed for my bike(89-90models)and part #3136 for the 91-92 models. i spoke to a dyno guy in melbourne and he said they just wear out ya slides in 4000k's... so im quite at a loss as to what to do

spoonman
29-03-2006, 01:56 PM
i fitted my 89 1100, 36ss carbs, with k&n pods...now i have to find a jet kit! i have done a little homework with the dyno-jet stage 3 kits. Firstly the Dynojet kit part #3136 is listed for my bike on dynojet.com, but after i emailed them they directed me to serco.com.au and they have got part #3127 listed for my bike(89-90models)and part #3136 for the 91-92 models. i spoke to a dyno guy in melbourne and he said they just wear out ya slides in 4000k's... so im quite at a loss as to what to do