Cam Chain Timing Question

So, I put the engine together ('78 KZ1000) and I set up the cam shafts with the carat on the exhaust cam pointing forward and flush with the head mating surface, counted 28 links to the "28  " mark on the intake cam. The lobes on the right side of both cams are pointing inward at each other. Everything looking cool. put on the cam bearing caps, tightened them in order to 7 foot pounds, installed the guide sprocket (with Liska risers) and tightened its bolts to 7 foot pounds. Then I hand-tightened the APE cam chain tensioner, double-checked that the timeing mark was still on the "T" for 1 and 4, and put a breaker bar with a 17mm socket on the crankshaft.
I rotated it 360 degrees (so the timing mark returned to the "T" for 1 and 4), and the cams only rotated 180 degrees, so the lobes on the right end were pointing away from each other.

So, what did I do wrong?

(as always, thanks in advance)

You did nothing wrong.
The cams run at half speed so two turns of the crank equals one on the cams to put them back to the original position and re-align the timing marks.
When counting the 28 pins you did count the one inline with the arrow timing mark as zero didn't you otherwise the intake will be one pin out (advanced).
If you count the one on the timing mark as number one it is actually a 29 pin count to the 28 mark.
Many people get caught out by that and wonder why the engine runs flat..

I did, and thanks so much for the fast reply. 

So, to be clear: there is a revolution when you reach the TDC mark, but those pistons are actually at BDC?

Nope. The timing mechanism is bolted to the crank. When it says 1/4 tdc, then those pistons are at tdc every time.

Yeah, that of course makes sense. I'm just trying to get my head around the cams being 180 off on each full revolution. Is there a wasted spark (when the timing passes the "F") in between firings?

One cylinder of a four stroke engine do a power stroke every 720 degrees crankshaft rotation and the cam shaft do only 360 degrees
The crankshaft sproket for the cam chain has 15 teeth and the cam shaft sprockets has 30 teeth = gear ratio 2 : 1
The ignition sparks every 360 degrees (power stroke) and the next 360 degrees into the exhaust stroke (waste spark). 
1-4 TDC = cyl. 1-4 piston at TDC and cyl. 2-3 piston at BDC
2-3 TDC = cyl. 2-3 piston at TDC and cyl. 1-4 piston at BDC

That was what I needed to make it make sense for me—thanks for the patience and the wisdom, everybody!

The cam chain sprocket on the crank has 15 teeth but the sprockets on the cams have 30 teeth so it takes two revolutions of the crank to equal one revolution of the cams.