in process of buttoning up a water pump upgrade on my bike '09 pump on the '07 engine. I was also getting a intermittent "Noisy engine - clackity clack" at startup but would go away in a few seconds. Thought it was the water pump ...... Today went to the bike shop " Scuderia in San Francisco " talked to one of the mechanics about the engine noise and apparent connection to water pump... Mechanic told me the water pump isn't something that ever makes noise , however when the water pump starts leaking and some water gets into the oil the oil system looses some pressure and the chain tensioner starts making noise ( The clackity clack ) ... I asked if once the waterpump and oil is changed will everything be ok ... Answer: yes - he didn't seem very worried either......

cheers

interesting, keep us posted