2 dead cylinders

Took my '76 KZ900 out yesterday and in about 20 miles the #2 & #3 cylinders went dead, #1 & #4 plugs are gray to white. It has been changed to electronic ignition in the past. Thanks for any ideas

Most likely the coil, associated wiring or ign pick-up that serves cyls 2 and 3 .
Swapping coils will confirm a dodgy one if the fault moves to 1-4 or rule it out if no change.
If no change then look at the wiring and then the ign pick-ups.
Which part of the plug is looking grey/white.

The firing ends are grey/white, doing good. Thanks

kz900er wrote: Took my '76 KZ900 out yesterday and in about 20 miles the #2 & #3 cylinders went dead, #1 & #4 plugs are gray to white. It has been changed to electronic ignition in the past. Thanks for any ideas

What do #2 and #3 plugs look like?
Is one of them obviously fouled?

While a weak ignition may well be the culprit, another possibility is when a too high fuel level causes an over-rich condition which fouls a plug whereby both plugs quit firing.

Good Fortune!