They have better mpg, but they generally don't have as much of the emission lowering 'tech' that cars have. This is especially true of older and/or cheaper moto

They have better mpg, but they generally don't have as much of the emission lowering 'tech' that cars have. This is especially true of older and/or cheaper motorcycles. So they'll burn less fuel, but each gallon of fuel they do burn will release more pollution, although motorcycles have gotten a lot better on this front over the past several years.