This is my first light bike, a 2011 supersix high mod. Ill get an updated weight, but i think it is 15.9. How light can i get withous sacrificing looks and performance?

Wheels american classic sprint 350
Tires. Ultremo zx and lugano
Shifters rival
Calipers apex
Read d. Force
Front d. Rival
Crank. Force
Seatpost. Zipp sl speed with shim
Seat. Arione cx carbon
Bars. Cannondale c3
Specialized griptape
Rxl bottlecage
Cat dual wireless computer
Headset. Ritchey
Stem wcs ritchey 4 axis

Thanks for your help

Your budget is very important in this question.

I had a 2009 SS HM and was 5.90 kg. Just swapped frame to HM 2010-11 and dropped 200g,

Now it's 5,70 kg (12,67 Pounds), with clincher and DA 7900 shifters and derailleurs.

A couple years ago cannondale was displaying a sub 10lb SS himod at the tour. As was previously mentioned, budget is a crucial part of the answer.

Not sure what that seatpost weighs, but the things that jump out are the brakes, bars and crank. Tubes are also an area where a quick 100gms can be shed. If you're on a budget, patience and eBay are you're friends, if you're somewhere where eBay is a good option. My Caad7 is presently 14lbs even with pedals, 2 cages, wheel sensor and mirror! And it is pretty much a budget ebay build. The most expensive components being the frame (~$300,nos) and the wheels(~300, 1430gms, new).
Weight is where you find it, only 28gms to the oz. and 16 of those to the lb.

My force crank? I thought it was one of the better lighter parts. I have one vredstein light latex tube and one regular, i forgot about that, i should get a second.

As far as budget, id rather buy a piece at a time, say this month i got the pedals and zipp seatpost. So here And there ill get anything within reason, i mean 300-400 for a part is ok, im not sure but i suspect there may be some Really expensive bits i dont know about.

Also, budget is limited by if all upgrades cost more than say a new and better bike, that would be poi tless. If it costs so much i could just get a new evo or something.

I forgot to mention i have speedplay zero stainless, which i hate

Is it BB30? Not sure what those weigh, but a C'dale SI SL or Specialized S Works will be ~ 580gms w/BB. You can find the S Works on Ebay for $200-250. The SI SL will be double that.

Bb30 frame weighs 890