I bought a set of new head studs and nuts from Sick Bikes and have installed them on my 48cc Grubee 2 stroke engine. However, two of the studs are higher than the other two, and when I put the nuts on them and try to torque them, they won't torque to 12 ft lbs like the other two did. I read on this forum (somewhere) that sometimes the Chinese don't tap out their stud holes all the way. I'm wondering if this could be the problem or if it's something else. Can anyone help me? I really want the engine to be as good as possible before I even install it and run it, and the two "longer" studs are scaring me!