I was able to get out also, but only to change the oil & filter.
The Belchertown Parade has to be one of the best ones in the areas, highly recommended. It runs along the common, (the fair itself is on the common, as you guessed). However, the parade was cancelled this past weekend for safety reasons.
I came across it one year by accident. We were on a ride and traffic there had come to a halt, so we parked the bike to see why. Enjoyed it so much, have been going every year since.
Speaking of leaves, there are plenty of wet ones on the roads now, so do be careful, 'specially going downhill.