I bought my Ninja used in February 2015. I low sided the bike in august 2015 making a right hand turn around 20 mph, the freshly paved road caused the bike to slide out from under me. The bike has a bit over 25k miles on it. Accelerating at high rpm's 3000 and more I hear a knocking noise. Sounds like a clanking sound. Accelerating at lower rpm's about 2500 or less there is no knocking. After reaching 35 to 40 mph the knocking stops. No knocking while idling. The knocking also doesnt seem present when the bike is hot. I just was on the freeway doing 90 mph so the bike got nice and warm. Upon exiting the freeway, taking off in first gear from a red light there was no knocking. the oil light is not on and has never been on since I've owned it. Other than the knocking the bike runs like a top. I've read laying down the bike can get air on the oil filter and can cause a knocking sound but the symptoms I read about weren't the same as mine. The other thing is the noise just recently started and I laid the bike down a year ago this month. This is my first bike although I've ridden for years and I don't know a lot about them. I'm not interested in taking the valve cover off myself as I'm not experienced in it and don't want to make things worse. I don't have the money at the moment to take it to a mechanic. Any ideas or suggestions would be awesome. I'm afraid that it's piston related and will cost an arm and a leg.