If you are building a single port motor I assume you are on a stock crank.
Stock (VW made) fans are good at stock and slightly higher engine speeds so no need for welded fans.
Aftermarket fans might lose a blade or two - can't comment.
You only really need a welded fan when your RPM is way above stock - by which stage your stock crank will be flexing like a brown banana anyway.
Just an assumption........
this is where you tell me that you have counter weighted your 1200 crank and you have super turbocharged a 1200 at 14:1 CR and have valve lift which you could drop marbles through........
'59 fully plastic bodied Wizard 2 seat roadster
Indian Scout 101ci
Originally Posted by mr slug:
"Best bike on the thread IMO, outright winner"
The Runaway Boy