inherited my brother in laws mm when he passed .it was in need of serious help. replaced parts: new mikuni carb ,universals timing and all gaskets ,starter battery ,wires ,rotor and cap,plugs,oil etc,full gasket rebuild and used original head .did timing and ran great but started having valve and lifter issues ,got another head used replaced all parts but rocker assembly and valve springs,ported polished and jet valve elimination ,had it resurfaced lightly,new valve where slightly longer than original ones so had them shaved down a bit.turns good cam was also polished .got everything back together and got truck running but I'm shfting into second and when I get toward middle of second I'm not continuing to build pressure to end of gear its getting louder but not picking up speed like it was before head swap??II NEED HELP.....PLZ