Stripped Idle/Mixture Screw

[Guest]

I'm rebuilding the Mikuni BS32 carbs that came with '80 GS750 I bought. They are/were in pretty bad shape. I'm also installing a DynoJet Stage 3 jet kit because I'm going to individual filters and put this motor in my racing hack which has a 4-into-1 exhaust system.

And of course, on the LAST carb I stripped idle/mixture screw.

I've tried heat and got it a bit further but the head is stripping so bad I'm fearful of doing more damage.

Anyone have a super-secret guaranteed way to extract it?

[Steve]

Just the tried-and-true "cut a slot in the tower with a Dremel tool" method.




Try to cut the slot to match the slot in the screw, if possible, to minimize hw deep you have to cut.
Use a heavy-duty reinforced wheel to make the cut, then use a GOOD screwdriver with fresh, sharp edges.

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[Kyler]

hmmm.... sounds like a better plan than trying to drill it and use a very small extractor!

[gsgeezer]

That's why you want to listen to Steve!!

[Steve]

That's why you want to listen to Steve!!

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[snicrep5]

i did the extractor method and of course it broke and compounded the situation. It came out alright in the end, but it pays to search and heed the advise of these veterens.

[Kyler]

i did the extractor method and of course it broke and compounded the situation. It came out alright in the end, but it pays to search and heed the advise of these veterens.

agree - nothing like advice from the "been there, done that" group

[Kyler]

update: got the screw out. Managed to run it all the way back in, chased the threads with a bottoming tap, drilled the screw and put a small EZ-Out in it and it backed right out.

Oh the joys of working on a 33-year old motorcycle.

[subforry]

I used one of these

http://www.dremel.com/en-us/Accessories/Pages/ProductDetail.aspx?pid=125

to sharpen the slot in the mixture screw. Worked great. I discovered that my threads were ok it was just that I was pushing so hard inward on the screw to keep the screwdriver engaged that the screw couldn't move outward. Once I cut/sharpened the slot it unscrewed like there was nothing wrong at all.