Motorcycle Repair: fireingorder, spark plug cable, plug cap

Question
Hi mark im building my 1977 kz 650 bike back i dont know what order the spark plug cable go could you help me please

Answer
Hi Carlos,

Cylinders are numbered left to right 1-2-3-4 when seated on the KZ.

One ignition coil operates cylinders 1 & 4. The other coil operates cylinders 2 & 3.

You may connect either plug wire from the same coil to either of the two cylinders that coil operates (both spark plugs arc together).  

You may be able to tell where which wire goes by the design of the plug cap. Straight caps go to cylinders 2 & 3. Angled caps go to cylinders 1 & 4.

The firing order is:
1-2-4-3

Respectfully,
Mark Shively