Gen rule is every 1" tire size change = 4 teeth rear sprocket differance. Every 1 tooth on the front = 3 rear teeth.
More teeth on the rear = more grunt, less top end
More teeth on front = more top less grunt.
I am running a 30 rear with 11 front (200e Auto-X) with 18 inch tire = very near stock overall. That should give you an idea.
85 ATC110 - The Greatest ATC of all time - (My First - new in 85)
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