Following news of the 110% edition, a long-stroke engine introduced a couple of weeks ago, OS Engine today announced O.S. SPED B21 Ty Tessmann II square stroke engine to be shipped in September.  

Ty II is based on B2101, the 2014 World Champion engine, with 5.8mm carb restrictor, which is his favorite.  And the new feature different from the original B2101 is that Ty II has a low- profile head of Ty’s original design, new shape and double height vertical fins compare to the latest model B2102.

The Ty II edition comes with a new 90mm long manifold + T-2090SC (combo set, code #1A20A), or engine alone (code #1A209)

See: O.S. Engines