stock muffler just ran in for one tank baffle still in muffler. 96 % humidity 90 degrees farenheit. apc 11/6 12400 still more left to peak out as motor is brand new and I always keep it rich when breaking in. idles at 1800 reliably with excellent transition. haven't needed to even touch the low speed needle. it just baffles me that these run so well for such an excellent price.oh yeah cool power 15% with a little castor added for the breakin run.