fly wheel balanced or zero balanced that isda questyonq

[amcfeek]

are fly wheels on older 2smokes normally balanced so the crank has a ofset of wheight outside the reciprocatin /roatating mass. or are they zero balanced. with no extra wheight and a perfect balance as if you put em ona buble balancer they aere eaquel wheight 360 degrees..
ok i have like no flywheel on my one 79 yz400 and i dont know if i can swap a diff flysheel in thats the same diamter big/little.. like from a dt360/400 70mm stroked 400 it/yz etc . or if i find one in my pile of crap from where i got the 2 mills from .just wondering if i can use one that just fits and the cdi works ...
you cant walk in my garage you climb .. like indiana jones . so it would take a bit to get daylight apon some stuff ..

ok porting question when some one says they have a bridgeport . is that like a blasters intake port . or like a 250'r exhaust cause they have a bridge in dem pots?

i also would mind hijacking a freinds lathe for a few lightenings .. {i took a nightclasss for machine shop so i know what a bridgeport is for.. }