good cal nemesis, having some choice on # of teeth for the rear could help out big time.
I also heard that the sprockets are gonna be ready in 2 weeks, plus they got a single piece D.I.D. 415 ER chain!!! So no more buying 2 chains to make one longer one.
Also there are only 5 of these available to order, so all you track rats or racers, step your game up. The 520 chain is totally overdesigned for the 250. Maybe it's because if you rearrange the letters in 250 you get 520.
I preordered mine from here:
http://www.aftermarketcycles.com/str...cket-set.html#