Carb butterfly seized?

[WinterHack]

So I've taken the carbs off my 1990 GS. It's been sitting for years, so isn't in the best of conditions.  Tried pushing the bit where the throttle cable connect, the left (or maybe it's the right) butterfly opens a little bit, but the left (whichever isn't directly connected to the throttle cable) is stuck fast. No movement at all.

I assume it should open fairly freely?


Also, I've ruined all the carb top and float bowl screws. Where do I find replacements?

[007brendan]

The two butterflys shoud be connected by an adjustment screw that controls the butterfly sync between the two carbs.  If one carb butterfly isn't opening, that screw is probably missing.  There's a member on this forum -- Buddha -- that sold carb screw replacement kits to switch out all those crappy JIS screw heads with allen head screws.  I'm not sure if he still sells them, but I'm pretty sure you could find them or something similar at just about any hardware store.

[WinterHack]

Yeah, I see where they are meant to be connected. There's a wee little spring, as you open the left one, the spring compresses and pushes the right one open. The left one (or was it right?) moves freely, within the bounds of that tiny spring, but the right one (the one the spring eventually pushes open) doesn't budge.

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[The Buddha]

Carb top and float bowl screws are the usual 5mm allen heads available @ any hardware store. 12mm length.
I stock stainless steel button heads, but any good hardware place you could get SS allens.
The stuck butterfly - may just need soak and clean. Just use penetrating oil and elbow grease, and patience and beer.
Excellent combo, always works for em.
Cool.
Buddha.

[WinterHack]

Carb top and float bowl screws are the usual 5mm allen heads available @ any hardware store. 12mm length.
I stock stainless steel button heads, but any good hardware place you could get SS allens.

So I am searching for "M5 12mm Allen"? Is M5 the same as 5mm?

The stuck butterfly - may just need soak and clean. Just use penetrating oil and elbow grease, and patience and beer.
Excellent combo, always works for em.
Cool.
Buddha.

It's soaking in penetrating oil as we speak.

[yamahonkawazuki]

pentrating oil is your best friend

[WinterHack]

Right, quick update, I would up having to pull the carbs apart to get better purchase on the butterfly axle thing, and managed to get it loose. They now are both entirely stripped down, and await the ultrasonic bath...

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