what size petcock barb for this common XS650 non-vacuum replacement

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Hello Crew:
I hope all is well for you this morning. it's 36 degrees here near Washington D.C. at the moment. I am using a generic xs650 replacement petcock on my 1981 Special with original tank. I am looking for a replacement barbbecause I broke the 90 degree one that came with it and can't find the extra. I ordered 1/4 npt x 1/4 ID straight barb. The one that was sent by Amazon was the wrong size. I think it was their fault.

Is that the correct size (1/4 npt x 1/4 ID) ? Please help if you can.

TO ALL OF YOU WHO ARE SOONER OR LATER GOING TO BUY THIS CHINESE PETCOCK, DON'T BUY FROM MIKESSX. THE SAME PRODUCT IS 20$ WITH FREE SHIPPING ON EBAY VERSUS 41$ PLUS SHIPPING FROM MIKES.

The picture was borrowed from another post.

I installed VM34 and trying to route the each fuel line each with a inline filter. Using a T connector hasn't worked well for me with the two filters.
I took the cap off the other side of the petcock, installed the 90 degree barb and was using the one petcock with the two fuel lines. It worked. But the 90 degree barb sheered off at the hole because I tightened down tight to many times trying to get the barb facing in the best direction. Thanks for any help.


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I'm getting 7mm x 1.0 on the two spare 90s I have. Nowhere near 1/4 NPT.

NPT threads would not have a sealing washer at any time.
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Hey guys, I went to autozone and took the straight barb, and sure enough, m7-1 is the right size. Thanks for all your help.
I'm getting 7mm x 1.0 on the two spare 90s I have. Nowhere near 1/4 NPT.

NPT threads would not have a sealing washer at any time.View attachment 257031View attachment 257032
Now I know what that gauge is for, measuring thread pitch thank you MacmacMac.
Thanks for all the offers. I took the straight barb to AutoZone and of course nothing like a m7-1.
I ordered a whole new $20 petcock before I saw your replies.
 
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