I can't believe it's that heavy, my 20" Steel Kona with suspension an gears came in at 24lb and I could lighten it quite easily.
Inner tubes, what you using. Generic Cheapo Tesco/Airwave can be 250g (actually not usre of Tesco's)
Drop to some 150g or sub that.
So a 250g inner tube to 150g inner tube would save you 200g (which is 0.44lb)
Of course you might have light weight inner tubes ?
and that 321g is 0.7lb
a few 50g here and there soon adds up into bloat
And don't listen to that man up there about the UN72's they are in the 250g region, un50-53 are in the 300 to 350g region. Only the UN52 dips below 300g but only by 10 or 20g and still heavier than UN72's
Of course FSA Ultimax and UN9x's are lighter.
Ti even lighter
Ti headset spacers add weight, splined Alu or carbon are the lighter one's
Without the weight of the other bits it's hard to tell.
Wildgripper, dunno which one's are they
http://weightweenies.starbike.com/listi ... e=mtbtyres
I'd go for grip and comfort over weight though in a tyre. The Maxxis 330 are light for a reason, they are race tyres and you'd kill them quickly and only good in the dry.