Gentlemen.... the rulebook(s) i've seen, although a few years old, have stated in Modified class, over 250ccs., you're permitted a maximum of 68 inch wheelbase. 60 inches under 250ccs. This is for ECTA and SCTA.
This may be outdated/superceeded/revised but was a general question concerning handling. I'm awaiting my new yearbook for the 2010 season.
It also states that OEM or Production replacement frames may be used having "similar" geometry. Similar meaning I "assume" stock production specs.
Bike will run in the 500cc Modified classes.
Thanks....... Morph