[ralferoo]

I'm not sure about actively deceptive. What else does it mean? Hydrocarbon emissions are what you get when you burn hydrocarbons - H2O, CO2 and CO. If it's referring to a different thing, it's not a hydrocarbon emission.

The image, and the claim within it, is actively deceptive because it's not true.

[honk]

It's a little messy, and it's not clearly disambiguated what concept the artist is referring to. I agree "Hydrocarbon emissions" could reasonably mean what you get when you burn hydrocarbons, but that definition can also include literal "Hydrocarbon emissions": uncombusted or partially combusted hydrocarbon fuel being emitted out of the exhaust after ignition due to non-ideal combustion. Like you mention, this is alongside CO, as well as elemental black carbon and other trace combustion products like NOx etc...

You're right that there isn't orders of magnitude more CO2 from a two stroke, but there are orders magnitude more CO, as well as these literal "emitted hydrocarbons", which I think it what the direct claim the art intends to illustrate with either dinfinition. But the fact we're having this conversation is evidence the claim at the very least isn't clear.