Went down and assisted my father with his Yamaha TZ350a (Number 50)
His bike is a production racing bike which came out as an out of the box race bike first produced in 1973. It makes 63hp and I timed him doing a 1.28. Not bad for a 38 year old bike with old technology.
Until next time,
Few more snaps here: http://www.flickr.com/photos/seanclarke4age/sets/72157628045951577/