Z50King said:avgas is designed for long stints of high rpm. wont really help a dirtbike out
Its also a dry fuel made to be used high up in the sky. If you use it often and dont add marvels mystery oil or somthing of that sort, It will burn up you cylinder. Friends banshee had it happen as it was bone stock and he thought avgas would bump it up.
I run 91 mixed with regular stock car race gas mixed 50/50. When i ran full race fuel it would have a weird RPM curve, But mixed it pulls hard through all gears on my mini or XR600R. I know its not needed, But keeps the carbon from build up. If you have parts that are always clean and wont rob HP, Im just keeping it where it was new and havnt had a problem yet.