SUZUKI GSXR750 Carbs Mikuni

[pggg]

For the XS1100, the 36mm slingshot carbs, I'd try one size up on the pilot jet and waay up to 130's 140's for the main jets for a first look, also with a performance type air filter and the airbox with its big velocity stacks rather than pod filters. And of course a decent flowing exhaust system. These other keihin cvk 36mm fit the XS easy as, no need to change much of anything, the carbs boost the XS motor like you wouldn't believe

[somesuch]

Re: Mik Slingshot

Bob, if the needle jets are worn, chances are that it is because the lighter colored slide guide/blocks are worn as well. They are not available anywhere in the US. People have fixed them with epoxy though. I have played around a lot with these carbs on my 90 and 91 GSXR 750s, and from experience most people with GSXR want to junk those, or at least go with the 38mm. These slide guides don't seem to last too long on a GSXR motor in my experience, and by 20-25 Kmi most people will have had a problems that are symptomatic of worn emulsion tubes.


--Nick

Originally posted by underdog57
Take a look ,,,


Gotta hit thye road , mains say 124 on them ...
The needle jets do look worn ...

Later

Bob

[moto]

Bob, if the needle jets are worn, chances are that it is because the lighter colored slide guide/blocks are worn as well. These slide guides don't seem to last too long on a GSXR motor in my experience, and by 20-25 Kmi most people will have had a problems that are symptomatic of worn emulsion tubes.

Hi Nick,

I currently have a limited quantity of those slide guides in stock.

Regards,

Derek

[somesuch]

Unfortunately I had sold both my XS1100 and the GSXR that used those guides.

Those people that are running those carbs, should take notice of this availability, as in my experience those slide guides are VERY hard to come by.


--Nick

[Spootinay]

since 1/40" (.025) drill bits are super hard to find, you can use a mig welder gun tip, available at ACE or home depot / lowes. they have .025 holes drilled in'em. stuff one of em in the vac advance hose and hook it to the nipple on carb number one.

but do you still get the fluctuation in vacuum when the suction is not interrupted by the butterfly valve during idle ????

does the vacuum advance advance the spark at all when the vacuum source is constant?

or does the vacuum source on the carb one nipple fluctuate the same amount as the original hole drilled below the butterfly valve?

[cywelchjr]

since 1/40" (.025) drill bits are super hard to find, you can use a mig welder gun tip, available at ACE or home depot / lowes. they have .025 holes drilled in'em. stuff one of em in the vac advance hose and hook it to the nipple on carb number one.

but do you still get the fluctuation in vacuum when the suction is not interrupted by the butterfly valve during idle ????

does the vacuum advance advance the spark at all when the vacuum source is constant?

or does the vacuum source on the carb one nipple fluctuate the same amount as the original hole drilled below the butterfly valve?

That will NOT work properly. The vacuum advance requires that there be little to no vacuum at idle to provide no advance until you advance the throttle, doing it this way will provide you with FULL vacuum advance at idle, which means that if you adjust so that your timing is correct under those conditions, it will be off for every other condition. The ONLY way you can do this is to have PORTED vacuum controlled by the throttle position.

[Spootinay]

thats what i thought. and it has to be ported right under the butterfly valve right?

[cywelchjr]

thats what i thought. and it has to be ported right under the butterfly valve right?

It does, but it also has to be done at just the right angle and just the right size to work right too. Fortunately you have 4 carbs, and you have 4 chances to get it right cause it don't matter which carb provides the vacuum.