A former owner of the infamous Nordturno writes:
I ran it as built, without a coolant bottle, during my ownership.
It was only really an issue when caught at traffic lights coming back in to town after a 'spirited' riding session on country roads.
John had cunningly wired an idiot light to the fan sensor (the fan was also absent). The bulb packed up, so I replaced it with a flashing LED version. So at least I had a visual clue that the fan would be operating if there was one.
It spat coolant on to my boot a few times but never blew the head gasket. For that kind of fun a big bore Frigerio conversion is the way to go
"Do not adjust your mind, there is a fault in the reality"
1957 175 Sport