Air / fuel mixture screw adjustment

I have the adjustment screws turned out at 2 1/4 turns each - the bike seems to be running ok - but havent taken it for a spin yet. I am a little puzzled because changing the screws either in or out doesnt result in any real change to the rpms on any carb. I seem to recall that when i took the carbs apart the main jets were # 107 ( factory calls for #110) and the pilot jets were # 45 (factory calls for # 40) is this a cause for concern or is normal ?

I tried to replace the small rubber o rings on the air mixture screws but couldn't find any locally - is there anything special about them -material wise - or will anything the same size do ?

 

Messing with the mixture screws generally doesn't cause any major RPM change; although it should change the "tone."

Those tiny o-rings are somewhat proprietary; check with XJ4Ever for the correct parts (see the logo in site banner, upper right.)

There is a lot more to the carbs than the mixture screws. Setting them at 2 1/4 or 2 1/2 is a good starting point; while you get your running vacuum sync done (with YICS blocked if applicable.) Once sync'ed, THEN it's time to fine-tune mixtures.

But before all that, your valve clearances need to be in spec, the carbs need to be religiously clean, and the float levels precisely wet-set.

As for the different jets, does the bike have a modified intake (pods) or exhaust?

 

Valves and Compression checked:
Intake #1 .13mm Exhaust: .18 to .20 comp: 150
Intake #2 .13mm to .15 Exh: .20 to .23mm Comp 155
Intake #3 .13 to .15mm Eh .20mm Comp. 160
Intake #4 .13 to .15mm Exh. .152 to .16 Comp 158

Adjusted floats to 3mm +/- 1mm measured from (wet) from @ gasket on float bowel. Also checked for any vacuum leads at intake boots - all looks good there.

The air filter and exhaust appear to be stock - no modifications. The bike has difficulty starting - choke on - once started difficulty maintaining idle even with adjustment to idle screw. When does idle - seems to jump around and not level off. Sounds like it bogs down. Spark plugs would indicate too rich - adjusting air mix doesn't seem to help.

What would be symtoms of either too much or not enough fuel in the float bowels ?? If for example the wrong ref line was used when making making previous noted float adjustments - would this adversely effect things ? AS previously noted the Main jets is #107 (factory #110) pilot jets are #45 (factory calls for #40) - I live more or less at sea level being on the West coast. Should I consider putting both the Main and pilot jest back to factory recommended ?