Hi, I am thinking of upgrading the valve head, my engines a CB125, running the CB156 big bore kit and higher lift cams, what heads are compatible, CB150, CB200, whats the biggest I can go?

Also any links *wink wink, to human* would be appreciated to a full assembly with the valves etc on... Ideally I want the head to have a rocker cover like this one:

http://item.taobao.com/item.htm?spm=...id=20684963459

Thanks in advance