not firing

Hi Guys, The saga continues, carbies back from ultra sonic cleaning and rebuilt with Honda repair kits. I have balanced the assembly prior to installation (needle under the throttle valve until it pinches and adjust all 4 the same) installed onto bike and it still will not go. I do have a spark at all 4 plugs (not a particularly strong one, to be fair) my questions are these.1. could poor spark be the cause? 2. How open should the throttle valve be when the twistgrip is shut? The manual says to adjust to the edge of the bypass tube but this leaves a gap of about 1mm to the bore of the carb, and uses up a lot of the idle adjustment, this seems excessive to me. All help, hints and suggestions appreciated. Carbs now off bike again so I can start from scratch. Cheers guys. Stevem.

I adjusted them in the way, that about half of the tiny hole in the bottom was visible under the butterfly. 1 mm gap seems to be quite a lot. Another method is to use 3/32" wide paper strip between butterfly and carb body. When it just slips out with light pull, the adjustement is right. Pilot screws 2,5 turns out.

its strange that the bike wont fire up with freshly cleaned carbs on, normally they will fire to some degree even if they are miles out of sync, especially with the choke on, as pekka says the pilots need to be 2.5 turns out,
i may be barking up the wrong tree, but have you checked the plug leads are not crossed over at the coil ends, one coil shoul do front cylinders, other should do rear.

Thanks for the tips guys, I guessed the throttle valve to bore gap was too large so I will close it down a bit, my pilot screws set at 2.25 turns out, I will tweak them. I also have the float height at 7mm not 7.5mm, is this critical? I am quite happy that the plug lead coil connections are correct but still puzzled by apparent weak spark. So back to the garage to, no doubt, be followed by much cussing and cursing.
Cheers Guys.