imo go back to the 1.2 needle and seat,that helps with rough terrain....imo 95% of the time the used mic n/seats are better than new aftermarket.....used ones may show wear marks,imo they are well lapped[to a degree, not excessive worn], bet I haven't changed 4 or 5 bad ones in 35+ years.i use an outboard fuel tank and primer line to bench test carb overflow/fuel levels