Topic: 72 cb350 help

[nsargeant]

for some reason after I am cruising at 60-65 mph for about 25 min. my right cylinder starts  to cut out.  It if I let it cool down it runs fine again. both of the plugs are getting good spark.  The fuel lines have NEW filters on them and the carbs are clean.  I htink I might have a venting problem because I will randomly look at the fuel filters and one will be full of gas and the other might not have very much at all in it. Shouldn't both the filters be full all of the time? How would I fix this?
thanks,
Nathan

[low-side]

Given the year this must be a twin.  They have the world's worst carb vent on them, a small brass tube with an even smaller hole in it that likes to varnish shut.  Probably your culprit if only 1 cylinder is cutting out.  Pull it off, hit it with carb cleaner and blow it out with compressed air.  Good luck with it.