Ok, this might hurt a little but I'm a little lost about the dome sizing in heads. I see a few people running domes from 18 to 20 give or take a few, but my question is there any that you can run that you don?t need to mix gas? And, if you have to mix can you run any dome? Now, I know it changes the compression but I see people with pretty stock motors running the same size domes as a modded motor. I looked over at Noss for a sheet or something on this and couldn?t find it. I have decided to go with Nosses head on this. But want to make sure I understand them a little more. Also, if it matters this bike will only see Sand. Thx for any info ::