Never have used a Colo-Tune from Morgan, but having a Morgan Carb-Tune for syncing carbs is definitely worth having, and yes, I have and use one. They're made and shipped from the UK for just a bit over $100. I have compared its readings with my mercury manometer and it IS spot on! Morgan Carb Tune uses stainless steel slides and no fluid whatsoever....comes with a carry soft case so you can haul it stored anywhere. The idea of having a liquid free and extremely accurate manometer came about to me from being a long time member on xs11.com. The 4carb Mikuni carb bank on the Yamaha XS1100 is particularly finiky for setting things and tuning, as are all carbs, even Kiehns on our ST1100's. Has been well worth the week wait for shipping time!Thanks for the heads up on the colortune gadget! Never heard of that before. Do you have info on the plug size in mm for the ST? So, how exactly does it work? How can I relate flame color to mixture at idle and while synching carbs? Sounds promising.
Never mind. Saw a video on YT. Pretty cool. Still need to set screws while running and not useful to sync.
Maubur, I totally relate to your logistics and was just trying to keep it simple for ya' without needing a lot of special testing equipment. A carb sync will unfortunately need the use of four vacuum gauges with restricors in the hoses ends such as un-used jets or such in order to nullify the needle fluttering or bouncing a bit. As far as idle mixture screws......an eighth of a turn one way or the other can and does make a world of difference in proper running and fuel consumption, and also a rich or lean cond. The other issue is the Morgan Colortune when used as instructed will leave each carb mixture screw an eight turn out, which is to rich. Set flame spark color as instructed.....then screw in mixture screw another eighth of a turn.