Need jetting spec's

[Rxl440]

Hi looking for jetting specs for gs750t just put a vance hines on it ,i have plenty jet's so i dont need a jet kit .I live in upstate ny Thanks for any help................

[almarconi]

Stock jets are probably 112's. I would try something in the 120-130 range.
The advantage of using a jet kit is the adjustable needles. You may need to shim the ones you have. You'll have to experiment to see how it runs.

[Rxl440]

I put a stage 1 jet kit in, 120 mains and the needles .Top end on the main jet at 80 it's flat did a plug read and she looks lean the weird thing is if i pull the air box cover she pulls hard up 105 wich you would make it more lean no change in the plug ethier should i go to 130 main or do need to change the plug to colder one???????
also i did check for air leaks and i have new boots on

[gearhead13]

are those 120's DJ mains? If thats a mikuni main it should be about right. Could it be your needle position making the plugs look lean?

[Steve]

or do need to change the plug to colder one???????

Generally speaking, there is no need to go to a colder plug. It definitely won't help with the jetting.

.

[Rxl440]

yes thats what came in the box 116 and 120 do i need to go to a cooler spark plug ? or put the 130 main in

[gearhead13]

What year is your bike?

[gearhead13]

A 120 DJ main is leaner than a 112.5 mikuni. I would go with a DJ 130 or a 120 mikuni main.

[Rxl440]

its a gs750t 1983 with a vance hines on it i have mikuni 115 ,130

[BassCliff]

Greetings and Salutations!!

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BassCliff

[almarconi]

i have plenty jet's so i dont need a jet kit

I put a stage 1 jet kit in, 120 mains and the needles

First you say you don't need a jet kit, then you say you put in a jet kit.

Well..Which is it??

If you are using the jet kit, you want the DJ 130 mains with the 4-1 pipe and the DJ needles.

If you are using the mikuni jets the 120 or 122.5 should work. You will probably need to shim the stock needles.

Keep in mind, that these recommendations are only a starting point, you will need to do further tuning.

[Rxl440]

Hi i did get a stage 1 kit its a 83 gs 750t .I put the dj 120 in and did a top end throttle chop plug read lean also at 80 it starts to go flat dose not pull .When i pull the air box cover and do the same run it pulls but not where it should be also the plug dose not seem much better has any one on here put a 4 in to 1 vh on this bike with a stock air box.Just wonder if iam fighting a battle with the air box,cracks from 20+ years old?Also ? on the plug going cooler wont help the jetting but when your pulling more fuel and air makes more heat could effect the plug range and not read right plus iam seeing it go down past 3 threads on the plug ? Also thanks for the welcome any gs's in upstate ny

[almarconi]

According to the directions included with the dynojet kit, you should be using the 130 mains with the pipe and pods.

Use a standard heat range spark plug.

If you have air leaks, either from a cracked airbox or carb boots, how do you expect to tune the carbs? Fix or replace the defective components.

[Rxl440]

Brand new oem suzuki boots just wondering if any else has had airbox issues dont know if its leaking but after 20+ years who knows.Winters are not good on some bike parts when the shop gose from cold to warm.The stage one comes with 116 and 120 mains .Now are pods the way to go with a cv carb i have heard good and bad, if i have a air box issue.

[almarconi]

Ok..you have kit 3102..is that correct? You should use the 120 mains.


Did you drill the slides? Are you three turns out on the mixture screws?

Where are your fuel levels set? You might want to try raising the fuel level, see if this helps your lean
condition.