Well that didn't take long..
Pulled the forks last night and the inner surfaces of the uppers are worn, obviously been over tightened at some point.
Quick look on eBay and I have some 2008 YZF 250 SSS enroute to me.
Will have to see about what other bits I need to get it done on the cheap.
Expect a new thread on valving the SSS once I get them apart.