1980 gs450 carb airscrew location?

[Guest]

hey all,
tearing down (or continuing to) my '80 gs450... have the carbs about 90% stripped on my coffeetable.. using the carb rebuild tutorial from the front page... here is my dilemma, A) it's a 450, so we have very little info around for them (as compared to say the 650+), B) it's a 1980 MY, with the CV carbs, which don't correspond to the photos available in the rebuild series.

I've been doing great during the teardown, lots of pics, everything into small bags, each one labeled as to where it came from, etc etc... but for the life of me, i can't seem to find the air screw... i'm sure it's still behind a plug... and i *think* i'm looking @ the right one, but really dont' want to drill anything out until i'm sure ..

So, here 'goes. i am going to *assume* that the top plug in the HORIZONTAL passage just above the throttle plate, is covering my air screw (see attached picture)...

I would love to get some feedback on this one!
Thanks all!

-Nate

*edit* pointer on picture

[exbellicus]

I just did a teardown on my 450 carbs yesterday. I could not get my airscrews out. If you look just above the hole where you removed your vacuum hose out of, there will be a screw there. The other one is in the same spot on the opposite side.

Where ya located?

[exbellicus]

Did you get replacement needles & seats?

[exbellicus]

Here is the air screw


This is the pin that I'm not sure what it does...

[jwegman]

I would hazard to guess that is a brass plug for when they drilled the hole down during the carb body manufacturing process and not a retaining pin at all.

[howling60]

I just did a teardown on my 450 carbs yesterday. I could not get my airscrews out. If you look just above the hole where you removed your vacuum hose out of, there will be a screw there. The other one is in the same spot on the opposite side.

Where ya located?

K, so, directly behind the brass plug seen in my picture. I just wanted a verification that I was about to drill out the correct plug, and not end up killing my carbs with well-intentioned, but mis-guided repairs :P

did you soak the airscrew w/some spray-in carb cleaner? gotta replace the oring anyway... hopefully the cleaner will help loosen everything up?

I am in Bangor Maine.

Thanks!
-Nate

[howling60]

Did you get replacement needles & seats?

I have not gotten replacement needles or seats, nope. everything has been looking in really good condition, aside from the "untouched 30 y/o carbs with gunk" factor. I did order new o-rings from cycleorings however. certainly looks like i'll be needing them

Now, while i'm asking questions... removal of throttle plates... i'm assuming get an impact driver into those screws to help loosen them? or should i hit them with the 'ol butane torch to break up loctite/etc? how about getting the throttle shaft out so the entire carb can be dipped?

-Nate

[Suzuki_Don]

Nate, Don't touch those screws or the throttle plates, leave them where they are. Especially not with an impact driver. You can dip the carb bodies with the throttle shafts and plates left in place. leave them in the dip just long enough to get them clean.

[howling60]

Nate, Don't touch those screws or the throttle plates, leave them where they are. Especially not with an impact driver. You can dip the carb bodies with the throttle shafts and plates left in place. leave them in the dip just long enough to get them clean.

K, good to know. aren't there seals on the throttle shaft behind the silver plug/cover deal though? by impact i didn't mean the hammer type, i use the real-deal.

maybe i can creatively get the carbs in the dip.. keep the throttle plates out.. hmmm *cranks up creative solutions*

-Nate

[Suzuki_Don]

The seals that hold the throttle shaft are made from hard plastic/rubber and can handle some time in the dip. Just don't leave it in there for 3 days though. Just enough to get them clean. leaving the throttle plate part out of the dip while the rest of the internals soak is a good idea, then just turn the carbs around and leave the throttle plate portion in the dip long enough to come clean. The important parts to be cleaned via the dip process are the small passages drilled into the internals of the carb body, these get gummed up and blocked with varnish.

[504-Ranger]

i cant get to this screw! theres a silver plate with a small hole in the middle

[howling60]

i cant get to this screw! theres a silver plate with a small hole in the middle

that's why i started this thread, the plug/plate on mine is brass, i *believe* you just drill it (CAREFULLY) out to access the screw.

-Nate

[exbellicus]

Nate. What are the chances you could send your 450 pictures where everything goes my way? My e-mail is in my profile. I thought I would remember.....apparently not!

I still havent got my air screw out. There was never a plate over mine, dang thing just won't come out!

[jwegman]

Please correct me if I'm wrong, but don't drill out the brass plug in the 2nd photo of post #4... As I understand it, it's there to block the machine process to complete the path bore as you can't drill a 90deg corner; they had to go through the top - that's why they plugged it after manufacturing.

[howling60]

Please correct me if I'm wrong, but don't drill out the brass plug in the 2nd photo of post #4... As I understand it, it's there to block the machine process to complete the path bore as you can't drill a 90deg corner; they had to go through the top - that's why they plugged it after manufacturing.

as far as i go, i will agree with you. I have updated my picture to include a pointer to clarify which plug i am referring to that may or may not contain my airscrew