[Weldangrind]

The jets don't necessarily dictate the fuel economy. The efficiency of the engine in good running condition determines the fuel economy.

As you indicated Hector, the plug colour is a very good indicator. If you intend to check the plug, one way is with a plug chop. Find a level road (on a day that is not windy), cruise at whatever speed you would normally use (80km/h is a good baseline) and shut the bike off without letting go of the throttle until the engine stops. Once the engine cools, remove the plug and you'll see the colour for that specific condition. If it is tan-grey in colour, you're right where you should be.

The way to increase economy after that is by making changes that improve effiency on the intake and exhaust side, removing weight, using synthetic oil; stuff like that. Every time you make a change, it's wise to do another plug chop.

Ideally, you'll increase efficiency to the point where you can cruise at the speed you wish with less throttle than you do now.