Kawasaki Forums - VN1500 Classic 1987 timings problem

I need your help! On a 1987 Kawasaki Vulcan VN1500 I adjusted the timing like this, first the front cylinder to the F sign then rotated 310 degrees counterclockwise and I adjusted to R as seen in the pictures. It's good? The engine does not start! Backfiring into the carb.
https://cimg8.ibsrv.net/gimg/www.kaw...47912a7e66.jpg
https://cimg7.ibsrv.net/gimg/www.kaw...ad6aef22a4.jpg
https://cimg9.ibsrv.net/gimg/www.kaw...cb0ef6b4d3.jpg
https://cimg0.ibsrv.net/gimg/www.kaw...d3192c3e65.jpg
The engine has been rebuilt, there is a spark, the fuel is fine, it has compression (new rings), the crankshaft rotates fast enough, my only ambiguity at the moment is: there is a possibility that the spark can be out of sync with 360 degrees, to spark when it evacuates not when it is in compression?