In reply to JLS:
Yes, you could be right.
Singlespeed is commuter, ride in to work, leave bike, ride home, leave bike, repeat - no maintenance so no jet washing etc., all the grit/road salts picked up will sit in there I guess, along with being constantly wet from this weather so I guess its no real surprise - just thought I would get more than 6 months out of one.
Def not changing to fixie, been there, done that, not doing it again - too old for that nowadays.
Oh the joys of bike maintenance - should maybe take the car more