i am looking to buy a 2005 busa from a local guy. the bike has about 15 k on it. when i went to look the bike over before buying and cranked it i noticed the oil light was fickering on and off. i looked at the sight glass and it looked like it was white....so my first thought was that the oil had water in it which made it look milky. but the closer i looked i noticed there was no oil showing in the sight glass. i asked him to add some oil and he put in a whole quart. it still did not bring the oil level into the sight glass but as it was going down it did clean the inside of the sight glass off ( which told me the sight glass was fogged from the inside). he didnt have anymore oil to add so im not sure how low it was, maybe a quart and a half or so. my question to you tech guys is this.....what caused the sight glass to fog on the inside. and why would a 2005 busa be that low on oil (didnt see any leaks or smoking). and how big of a concern is this? should i steer clear of this deal? and p.s. the engine ran smooth with no knocking or clanging.....any advice or tech info would be greatly appreciated. also does anyone know what it would cost to rebuild this engine if it came down to that?