reliable

Hey guys I'm thinking about getting a new engine for my bike soon and I was wandering what engines are the most reliable but also with good power budget is 500 - 600

Hi Guys I am wondering what your thoughts are for a 125 race engine, we want reliability and torque and hp , the moment the gearbox in my daughters current quad , smashed the selecter gear between 2nd and 3rd gear , she is racing Motor cross on her quad, the engine is a yx 150 bottom end...

Hey, It's not long now before i get my long waited motorcycle L's. I wan't to buy a Motovert RX 125 new. But i am a bit skeptical as i know these bikes have some Chinese parts. I plan to use the bike as my only way of getting around, to work, school etc. Is it reliable, what problems have...