Injuring your back is one of the worst things you can do. Fortunately, it's also an easy area of the body to add serious protection to. No matter who you are, what you wear or how you ride, you can benefit from wearing one. This is how to do it. These are the best motorcycle back protectors you can buy.
Back protectors are certified to one of two safety standards: CE1 or CE2. They're both pretty safe, but CE2 halves the amount of force that's allowed to transfer through to the rider's body. Typically, that comes at the expense of weight and bulk. Many suits and jackets are sold with non-CE-rated foam inserts. These provide no quantifiable protection in a crash and should be replaced immediately with something that will.
The safest back protector is the one you wear more often (preferably all the time), so buying something that's inconveniently sized, shaped or that's awkward to wear may actually be a less safe decision than buying something that's easy and convenient.
Straps vs Pockets:
Strap-on back protectors cover a greater area of your back, but have to be worn separately and can be inconvenient as a result. Back protectors that fit in the provided pockets in jackets are fit-and-forget, but may not cover your lower back or coccyx all that well. They also work only in the specifically-shaped pockets they are made for, so you may not be able to transfer the protector from, say, an Alpinestars to a Dainese jacket or even between different models within the same brand. In the case of wanting to fit a back protector into a provided pocket, the best product is simply the one designed to fit it.
With all that understood, let's look at the different kinds of riders, their needs, habits and try and identify which protectors will work best for them.
The Casual Rider:
Alpinestars Bionic Air — $120
This is what I wear under my armored Vanson AR2 when I'm just riding around town. Because it's CE1, it's light and slim and the perforated design vents extremely well. No sweaty back here. And, because it's a strap-on, it covers the entirety of my back, from neck to tailbone. I've crashed in this and it provided excellent protection and I'm still able to wear it virtually every day. So slim, it won't alter the fit of any jacket and works with literally any item of riding gear.
The Backpack Wearer:
Kriega Back Protector Insert — $75
This multi-density foam protector is made by Forcefield, it fits into any Kriega backpack and, despite being light and slim, manages a CE2 rating. It also covers a very large area of your back. Back protectors are a particularly good idea to wear with a backpack as they provide protection against the contents of the bag, which could be hard, sharp or both and injure you even in a light fall. I've had one of these fitted in my Kriega R35 for a year or more and it's super convenient, providing protection without taking up volume.