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allankelly1:
Yes air filter. Is new too

Best wishes Al


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allankelly1:
Hi all

Ok wound out all four air screws 2 1/2 turns and center electrode are a bit lighter and browner than the plug in the picture  if that make sense

Also bit the bullet and got some 38s on order from Allen’s performance so I can down down size from 40 to 38 to lean the mixture slightly

I guess when I fit the jets should set screw around.  1 1/2 turns out to avoid a possible lean mixture and do another plug chop

Also notice on a warm day she is almost happy to do a cold start without choke so I presume that also points to a too rich idle jet

Fingers crossed this sorts things

Catch up soon

Best wishes Al


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K2-K6:
It's very low risk from a lean-ness point of view as you are making small changes that have very little impact on full load running demand at which error can have significant effect.

There's a very good routine for setting and evaluation of idle airscrew adjustment in Honda's own manuals from this era (often overlooked or ignored) that will let you see what you've got.

Warm engine and set tickover on main adjuster to give smooth running (after setting airscrew to 1 1/2 out) then on one cylinder at a time wind the screw out while running until it reaches a peak rpm, any more lean it should start to falter on that cylinder and confirms you're too far. Then from that peak rpm setting, wind the screw in again very slowly to get a 100rpm drop, at which point you've put just enough fuel back into the cylinder to run it slightly on the rich side of true combustion equivalent. 

Then adjust the overall tickover again with your main tickover speed facility and start on the next cylinder,  repeat until finished and that will set the mixture competently. 

As Julie indicated,  you can end up with slightly different settings from carb to carb , but this is the true setting calibrated for each of your individual cylinders as it exists then.

If you want to record where each one ends up,  that's the baseline tailored calibration for you engine.

allankelly1:
Hi K2-K6

Just a quick one to say thanks for all the advice

Got jets last night from AP and as it’s wet out spent some time in the garage and  now all fitted with 38 idle jets and I have set the air screws 1 1/2 turns out.

Interesting with 2 1/2 turns out on all carbs and running the original 40 idle jets after a run out last night to a bike meet plugs  now look like  this for cylinders 2 and 3 checked today (checked 1 and 4 originally as plugs easy to get too





 
So a nice clean central electrode with some soot on the earth electrode so cannot it be too far away from idea set up and hopefully going  slightly smaller for the idle jet will allow the bike to run with air screws out by about 1 1/2 turns and improve / crisp up the initial throttle response

Also now set the plug gaps at 0.5mm as you suggested

Raining hard now so will call it a day but looking forward to testing the new set up

Have a good one

Best wishes Al


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Laverdaroo:
Any update on this, I'm getting ready to fire a new motor and all the diagnosis info on here is fantastic. Did you get the result you wanted with the smaller idle jets in the end and was there any conclusion on the overall crispness and delivery?

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