Float needles too short?

[Kube]

So after about three years of trying to figure out why my carbs won't stop spitting gas from the overflow tubes I may have stumbled upon the problem. I thought maybe if I dropped the needles in the seat without the floats and spun them around a few times it might help them seat better. When I dropped them in I discovered that they dropped all the way in without any sort of resistance. As if they might be just slightly too short. These are aftermarket needles. I'm not sure where I put the originals. Is it possible I somehow got the wrong size needles? I ordered them from JC Whitney and they are supposed to fit my 79 cb750f. Has anyone heard of this happening? If so, any advice on where to order a new set I can be confident about?

[TOOLS1]

It could happen, but if it were the problem the gas would pour out the overflow tubes. The needles do not stick out of the seats very far, just a fraction of an inch is all. Have, you tried polishing the seats with a Q-tip, and chrome polish? If, you do need new needles, try vintagecb750.com
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[Kube]

That's exactly what happens. It pours out of the overflow. I've tried polishing the seats with no result. Carbs have been cleaned thoroughly several times, gas is coming from a clean external tank and I even added a filter just in case. When I put the needles in it doesn't feel like they're even making contact with the seat or if they are it's only very light. I'm about ready to chuck the whole bike at this point and probably would have if it weren't for the sentimental value. As cheap as needles are I figure it's at least worth a shot.

I did find this article. I realize it's talking about the gl1000 but if it could happen once.

http://www.randakks.com/TechTip26.htm

[TOOLS1]

The GL 1000 uses the same carb as the 79 CB 750.
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[Lucky 1]

You cannot polish seats to repair the damage. Buy new ones.

[Kube]

The seats don't appear to be damaged at all. I only polished them to clean them. Where can I even find press in seats?

[Lucky 1]

Look at the float needles with a magnifying glass. Really look.
If they are the all metal needles you will see a shiny ring on the bevel point.
If you look real close it is actually a step worn into the bevel surface.

On the rubber tip needles the rubber tip under a magnifying glass may look ok,
but spin it in your fingers and you will see that it is not concentric.

Honda stopped using the metal float- they went to rubber tip float needles because the engine vibrations would effect the float needles causing wear. When they went to rubber it helped dampen out vibration but you will notice a little wire clip on the float needle that hooks onto the float because just like a rubber cork it can get stuck. The modern fuels are another problem.

If your bike has a sticking float, buy a new complete set with needles and seats if they are all metal.
If they are rubber tipped you only need the needle. (Unless someone polished them and possibly caused damage to them.)
BTW the rubber tipped needle and metal tipped needle cannot interchange because the angle of the bevel tip is different. The rubber one is larger at the base of the cone.

Having new float needles is like 90% of the carb rebuild.

[Lucky 1]

Don't worry about that now.
Just get new needles. Adjust your floats and see what the results are.

[Kube]

They're the rubber tipped type. So were the ones I replaced. I can't find what I did with the originals but they must be around somewhere. I never throw away an old part until I know the new one works properly. Floats move freely. They don't stick at all as I've cleaned everything pretty well.