This is a terrible bike to ride.

Those are the first words you'll hear in "This Bike Has MS," a campaign by Grey Australia for nonprofit MS to raise awareness of multiple sclerosis ahead of the MS Melbourne Cycle in early March.

Multiple sclerosis is an exceptionally weird and annoying affliction. It's the most common autoimmune disorder to hit the central nervous system, resulting in all kinds of wonkiness: Take all the tiny icks that result when you've sat too long on your foot, had an off-season allergy attack, walked too long up a hill or haven't eaten in a while. Combine them, magnify them by 10, and try living that way.

You may feel tired, randomly numb or dizzy. You'll feel pain or have trouble thinking, managing emotions or even walking properly. There's also insatiable itching just under the surface of your skin, tremors, and hearing and vision loss. The symptoms can happen in spasms over the course of your life, or just get progressively worse.

It's notoriously also difficult to diagnose—and worse still, to take seriously. The ad points out, "With a disease like MS, it's hidden. People just don't get it."

For all intents and purposes, the bike shown below looks fine, much like your typical MS sufferer. Created by Carol Cooke, a cycling Paralympian, with a team of bike-building experts and people with MS, it's a near-perfect way to show people what it's like to live in an afflicted body, short of having the disease: What you can't see from a distance will drive you crazy once you've mounted it.

"Its gears are unpredictable, its frame off-balanced, and its brakes numb to press," the ad's narrator continues. "This bike has multiple sclerosis."

A great bike is an extension of your body, as intuitively responsive to the left-aiming twitch of your shoulder as it is to a hard squeeze on the brake. This one is saddled with maddening inconveniences: a numbing BMX riding saddle, dull brakes, missing teeth in the gears, thin handlebar tape with hidden ball bearings, crooked wheels, and a deliberately misaligned frame.

Users should feel a certain "dizziness of shifting, a real kind of unease tied in with designing an off-balance bike," says bike builder James Macleod.

"You have to constantly be fighting the bike to stay straight," highlighting how much harder an MS sufferer has to work to accomplish everyday tasks, adds fellow bike builder Thom Pravda.

"After some distance, the rider will start using muscles that wouldn't be natural," Macleod says.

The work also points to something we intuitively know, but don't think much about, partly because we don't have to, but also because it's just so creepy: Our bodies are machines, mostly fluid and delightfully responsive without us having to consider the mechanisms that underpin every whimsical movement. But they can also be subject to terrifying malfunction, the likes of which will make you appreciate the small graces you're afforded when everything works fine … like the ability to manage your bladder, or even walk straight.

"Multiple sclerosis" refers to scars in the white matter of the brain and spinal cord. It typically hits people between ages 20 and 50, and is more common in women than in men. In 2013, 20,000 people died of it. Nobody knows what causes it, and there isn't a known cure.

For more sensations of MS by osmosis, check out this comical description of the symptoms written by a sufferer. And if you feel sufficiently moved (hopefully without tingles or numbness), support the MS Melbourne Cycle, which is celebrating its 10th year and has so far raised just shy of AUS$20,000.