Hydrocarbons are simply a molecule of Hydrogen and Carbon. It is the Hydrocarbon chain length* that makes Natural gas, gas, diesel fuel, oil, etc. Thats how we get so many different things from the same crude oil. It literally comes from a teated stack that we siphon off what we need (the length of chain) at different levels, not unlike a distillery! Yum.
So, ya. HC is the foundation of the gasoline in your bike, but any length of the chain (incomplete combustion) is bad, mm-kay, even including oil vapor that the PCV system sends to the explosion factory. The goal is complete use of the whole HC chain, and any HC not combined with O2 at the end of combustion goes out the pipe.
*Simple Jack warning.