Yes BS38, same float used from 1970-79
While you have them apart check your jet sizes and that they are genuine mikuni. It's real common for guys to buy rebuild kits. While chinese brass is often a bad idea, the XS650 used different size jets nearly every year, most kits NORMALLY have the wrong jet sizes in them. It might be a good idea to post up pics of your carbs and report the jets you find, lots of carb swapping is done, you
might have carbs from a different year....
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