How to protect one's lungs while driving a motorcycle through heavily polluted cities?

I drive a motorcycle, occasionally in heavily polluted areas in developing countries. Sometimes the smog is quite bad.

The above image may look like a broken down bus to some, but it's actually a fully operational bus, and quite a common sight in many countries. Image source: India’s Diesel Subsidy Spurs Pollution Worse Than Beijing, Bloomberg 2014.

When there are no (at least enforced) regulations on engine standards or maintenance, you often see vehicles that are pouring out dark smoke that smells quite bad. When you are in the middle of traffic you often have no escape and end up breathing heavily polluted air. Also, the gasoline used is often leaded, which is dangerous. When diesel is cheaper, many drivers also use mixtures of diesel and gasoline. The fumes caused by that are again quite bad.

My solution thus far has been to wear a mask like this:

Is this mask actually useful? To me, this mask seems good at keeping harmful pollution out. When I wear it, I can hardly smell any of the foul pollution anymore. But I'm certainly not an expert on the subject, so input is very welcome. There are also some downsides to the mask.

1. It's too bulky to fit inside a normal, full-face helmet.

Full-face helmets are preferable when driving in large cities where traffic is typically ferocious and dangerous.

2. Due to the microscopic holes and the resistance in the filter, it greatly increases the energy used for breathing. I guess it's good exercise for the lungs, but it's also tiring and uncomfortable for long drives.
3. It's warm and sweaty.

But, of course, I still prefer the mask over breathing polluted air.

I have also tried this sort of mask:

From my layman perspective, the main thing that worries me about that sort of mask is that I can still smell pollution and fumes through it. Somehow that just doesn't make me feel satisfied that the mask is protecting my lungs from dangerous substances. Is this assumption correct, or is such a mask actually fine?

I also know that there are compromises between the two, but I am not an expert on such masks and I don't know how to judge what masks are actually protecting me.

Is it possible to drive a motorcycle through heavily polluted cities while wearing a full-face helmet, and also properly protecting one's lungs?

What sort of criteria should one look for when selecting a mask? Is is possible to combine safety and comfort?

I'd consider getting a half-helmet and combine it with the first mask pictured above. Still, It would be useful to get some input from others.