The carbs are electronicaly adjusted to compensate for temp and altitude .There are
2 solinoids on each carb one low one high speed ,controled by a computer .It has 5 in puts atmospheric pressure,throttle position,
air tem ,water temp and cdi unit . What I don,t know is to what temp and altitude it
compensates for ,and does it do any thing to timming .I have the Yamaha factory shop manuel and it gives me just enough info to
diagnose and fix it .Iwould like to under stand it better so I can cheat the system .
Thank you for your interest.
Willson