A few months ago I had to replace the floats in my Cali III carbs as they had become porous.
The originals were the old black solid floats but I replaced them with the hollow white nylon type and they have been fine until yesterday.
The bike started up fine but began to run roughly after a couple of minutes and I saw that fuel was pouring out of the R/H carb breather pipe.
When I stripped the carb down I found that the pivot tube on the float
had expanded just enough to bind against it’s supports at each end. A couple of minutes with a very fine file cured the problem but I thought I would share this with others in case the problem occurs on their bike.
Personally I blame the E5 fuel but perhaps I’m just paranoid.