Jetting issues after head rebuild

Didn't look bent, the flat head is just about completely stripped/unusable with how difficult it is to screw in. I have to really torque it to match the other screw's 0 point. It pokes out the tiny carb hole with no sign of being bent. Let me try swapping, but I'll order another set as I need to anyway.

What could this be a sign of?

EDIT: I was wrong, it's on the other carb.
 
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Is there a place other than Mikes to get the mixture screws? My one was on its last leg and it needed drilled out to get it out. So now I have the rich issue and I need mixture screws. Pandora's box is opening up...
 
650Central may have them as well but they would most likely be the same part Mike's sells.
 
Ok, after about 45 minutes of cleaning the mixture screw hole with a pipe cleaner, I'm come to believe that brass dust particles pretty much stripped away the screw on the right side (the left side is the rich side). I think I have it pretty cleaned, but probably should run a tap in there. I don't have the right size, it looks like some-something X .5mm. And I need new mixture screws. So that will be another $40 for screws and a tap.

But should I bother? Should I just save up for some nice VM or PWK carbs?? I see a huge thread on the Mike's PWKs and the quality issues, yet a lot of happy people.


I also have another option for a free set of "supposedly working" '79 carbs.
 
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The '78-'79 BS38s are very nice. I think they're about the best of the 38s.
 
I bought some mixture screws from mikes and never used them. They had a different taper on the end. The ones that were in the carbs had a step and were longer. They might have worked I needed the rubber O-ring. I gave up on the 40 something year old carbs. Bought some Keihin CVK 34MM carbs no more carb problems. I can send them to you no charge. They may work.
 
Which ones were they? I'm pretty sure I need 80-84. I haven't seen these free carbs yet, tho, so I might need to take you up on the offer (thank you!)

70-75
48-5008.jpg


76-77
48-5009.jpg


78-79
48-5010.jpg


80-84
20020902-floatneedleparts.jpg
 
Maybe but maybe not. Some of the mix screws Mike's was selling for the BS34s appear to be a non E.P.A. version, maybe a "world" version? They're not stepped but just have a tapered point like '77 and older non E.P.A. screws. The E.P.A. started clamping down with the '78 carb sets. The mix screws became "stepped".

80-on Mix Screws.jpg


Although I've never tried them, they may be a better, richer running screw as compared to the pollution mandated one. They probably don't require the 3 to 3.5 turns out either like the stock screws do.
 
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Should have tried them 5 twins has a valid point. That looks like what they sent me. Being somewhat dubious about some of mikes carb parts. I didn't use them. Send me a PM I will send them to you.
 
Awesome thank you!
Does anyone know the mixture screw tap size for the 80-84? It is too fine and big OD to match any of my taps in my set.
 
Thanks again Scabber!

I'm guessing the screw is M6 X .5 mm. It looks the same diameter as my M6X1 tap, my thread measuring tool says .5, and the M6 tap's threads perfectly match every other thread on the screw... sound right?
 
No, I think an M6 would be too big, and the standard thread pitch is usually 1.0 on an M6. An M6 is what holds your side covers on both sides of the motor. Take a look at one of those Allen screws and you'll see they're much larger than your mix screw. It's also the size holding your manifolds on the motor or clamping your clutch and brake lever perches to the handlebars.
 
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The ones I have Came in a tour max bag # 48-5012 I ordered the 48-5011 Mikes sent these I see they crossed out the 12 on and made it a 11 on 5 twins pack.The needles are the same.
 
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This was just a pic I found on the internet somewhere so I actually never ordered or saw them in person. If I were running a set of BS34s, these are certainly something I would try. I'm certainly all for clean air but wish they'd pick on someone else like city buses or something instead of strangling our poor motorcycle carbs, lol.
 

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