Ok i have this YT125L I picked up a few weeks ago and for some reason it has good pick up in first and second, but third, fourth, and fifth (you can barely even go anywhere in fifth unles you totaly max fourth all the way before you shift)seem very underpowered. It seems to bog down a good bit, what's the deal??? The carb is nice and clean and the plug looks good. Also when you rev it high it makes like a pinging vibrating noise, sounds like it will fly apart but obviously it does not, could that be rings maybe???? Or does it sound more like something lose, it seems to me like it was comming from the top end. I was thinking that if it was rings that it wouldn't start as easy as it does. Also I have been running premix with the oil injection disconnected to be safe. Anyone ever messed with one of these to give it some good pick up, or done any gearing work with one???