I am clear on the first class I want to run, as there is another similar bike that ran this year. I have a 1954 BMW R25/3. I understand this qualifies for the P-PV 250cc class. The bike is 100% stock, and this model is pushrod valve operated. I understand that I can do whatever I want to the internals of the engine, as long as the displacement remains under 250cc. That means stock head, cylinder, etc. Visually it must appear stock from the outside, but I can port, polish, tune, and cam it all I want.
I want to know what class I would run if the above bike had a "modified" engine, basically the same stock engine I described, except for non-stock carburator.
Thanks,
Daniel