Check the colour of your spark plugs, they will indicate if the bike is running too rich.

Often called a 'plug chop' - try searching for the term on here for information (if you don't already know how to do it).

Alternatively, read this: jetting

Then come back and ask any questions you have.
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball