I have spent a little time recently fettling my z650 in between the s1 restoration.I have had the wheels rebuilt with new spokes,fitted new tyres and given it a general mint up including a service and rectifying a long standing running problem which was traced to incorrect float heights. 
 
I have not spent a lot of money its been more effort and elbow grease. 

 Which the recent massive increase in z650 values i need to look after it 
 