I bought a Bud head some time ago, but I don't know which dome does what really. I would like to know more about the chamber shape and how it changes the performance of the engine. It's for my 03 125SX and I have provided pics so hopefully someone can educate me on the finer points. I also have an FMF Shorty silencer that I use on this bike, I like midrange torque. The last pic is the stock head for reference.