Vacuum pipes on CB750FO

[Bryanj]

There are holes but not "jrts"

[Dave B]

OK,
Some progress .
Carbs cleared again and reinstalled.Still won't start.
Used Easy start spray.Still no go.
The plugs are wet and good spark.
However i have just checked the points.
One side is intermittently sparking the other set not at all.
Do i need to fit new points and condensers?
Cheers,
Dave

[K2-K6]

Make sure choke is open (that's off for normal warm running) then hold the throttle open fully and crank it to see if it'll at least cough or make any indication of firing.

Obviously,  shut the throttle if it goes.

[Dave B]

one little weak cough
then nothing

[K2-K6]

Sounds slightly encouraging and you seem to have all the components of running.

What that should have just done is to dry out the combustion chambers a little such that it will at least ignite with the spark you have.

If you do the same again (cranking with throttle wide) then pause and give it a spray of E-Z and repeat to see if it'll catch it.

[Bryanj]

If your slides are too open with throttle shut what you describe hapens