In a way your asking 2 questions!!! 1st, the 28" tires, 2nd, the tire selection!!
I was considering a taller tire to get more roll..for top end speed, I think clutching would come into play...AIRDAM's clutch mod's sound appealing for that.
As far as tire selection, they look pretty aggressive, they'd probably be perfect some and not so for others...How's that for a non answer!!!
Yes, on the clutch work...but it could have had more. Yes it would have helped, but the size and weight on my 700 cc engine are big hp robbers. I replaced the Terra Cross tires which weigh less than the Spartacus....big difference.