Hey guys, I've really been looking into the Ninja 250's lately. I've read that after around 30,000 miles, the engines need to be changed out. I was wondering what specifically goes wrong. If it was the connecting rod, or a piston, or a crankshaft or something, wouldn't it be easier and cheaper just to order those specific parts, and change them yourself so you don't have to buy the whole engine? I'm looking to get an older one so that if I dump it I won't feel too bad for messing the stuff up that much, and if the miles are high on it, I won't have to worry about finding a whole new engine to transfer. Thanks alot.