i got a 400ex with 30 for compression. the first ring was stuck close. idk why but w.e so i figured since i got it apart. i bought a wiseco 11:1 piston 86mm. nothing crazy. im a bigger kid and i heard that going higher compression you will blow head gaskets alot. so should i just invest in the 65 bucks for heavy duty studs. or would you think it would be fine. also what about valves its only 120 bucks for new oem valves with seals. i was thinking about changing those. is all this worth it or not. also can you tap and do the studs urself or is it way better if i brung them to a machine shop?