Danny, would it not be better to split up the existing forum & give them areas to post in. There are lots of topics which will be common to both. If you then introduce other groups/makes they can integrate with the format.
Might be an idea to start one for the chinese buggy market as there isn't one on the go.
I did start one off but lack of time didn't see it through its not a big community at the moment but it seems to be growing quite fast, maybe some potential freestylers there after they discover the poor quality of some of the chinese buggies.