Are The Alpinestars T-SP and Stella Gunner Jackets Waterproof? Here Are Our Test Results

Some bikers are hobbyists that won’t go out if there’s even the slightest of clouds on the horizon, but others won’t bat an eye at taking a ride in a rainstorm. For the most hardcore of bikers, a waterproof jacket is necessary - sometimes you just have somewhere to go when the weather isn’t great.

Check out our review of Alpinestars’ T-SP and Stella Gunner Jackets, which attempt to keep bikers dry while they’re riding in the rain. We put these jackets through our unique waterproof test that shows just how good they are at keeping you dry.

The Basics

First off, the Alpinestars T-SP is the version of the company’s jackets for men, while the Stella Gunner is a similar version for women.

The jackets are made out of polyester that’s been coated in polyurethane. The only color they come in is black, with small white details on the chest, shoulders, and forearms. It comes in a lot of sizes, meaning you’ll certainly be able to find one that fits. The jacket starts in small and goes all the way up to 5X-Large.

Since Alpinestars intends these jackets for motorcyclists, they’ve designed them to be waterproof and provide protection in case of accidents. Both jackets have Nucleon Flex Plus Armour in both the elbow and the shoulder. The jacket also has polyester internal reinforcement to provide additional protection.

Alpinestars markets the jackets as both waterproof and breathable, which often involves a tradeoff between how waterproof a product is versus how breathable it is. That’s what we’ll take a look at in the next section.

Waterproof Testing Results

Our waterproof test has three stages that evaluate the performance of waterproof products in three different conditions. The Mist Test is comparable to light rain or generally misty conditions. The Rain Test is closer to a storm or torrential downpour, while the Dunk Test is exactly what it sounds like: one of us puts on the jacket and jumps into a pool. Yes, we get wet, but we do it, so you don’t have to!

The Mist

The T-SP and Stella Gunner’s construction is a bit of a strange jacket to test because the waterproof layer is on the inside rather than the outside due to the thick polyester meant to protect riders against scrapes in case of a wipeout.

So, in the Mist Test, as well as the more extreme ones to come, the water soaked through the outer layer very quickly. On the bright side, the water didn’t make it through the waterproof layer, so we were still dry. However, less happily, wearing a jacket thoroughly seeped through in water isn’t very comfortable. We noticed that the jacket became much heavier and bulkier and restricted and our range of motion.

The Rain

The main difference between the Alpinestars T-SP and Stella Gunner jackets performance on the Rain Test and The Mist Test was the speed at which the water soaked through the outer layer. Instead of taking a few minutes, the outside of the jacket was fully wet almost immediately.

However, even in more extreme conditions, the waterproof inner layer held up to the challenge and kept our tester dry. We can say that, even in driving rain, these jackets will keep you dry while you’re riding.

The Dunk

In the dunk test’s fully submerged conditions, the jacket wasn’t able to keep our tester fully dry. This isn’t a surprise, though; no jacket is fully waterproof when it’s submerged because they have holes in them for our heat, arms, and torso. Water is always going to work its way in there. That being said, the jacket did provide some protection because its form-fitting shape kept out some of the water.

All and all, this test doesn’t provide too much useful information for someone thinking about buying the jacket. If you’re riding a motorcycle and end up fully submerged in water, you’ve probably got bigger problems than being wet.

Other Features We Like

The Alpinestars’ T-SP and Stella Gunner Jackets have a few very nice features that add to their value.

Most notably, the jacket comes with a removable thermal insert that makes it appropriate outerwear for any season. You can ride without the insert in those warm spring showers and zip it in when the temperature falls.

There are adjustable straps on the waist and cuffs so that you can adjust the jacket to your unique body shape and ensure the jacket remains snug while you’re riding. If you do them up tightly, it will also help with keeping water out in the rain.

The jacket’s low profile collar was comfortable and won’t interfere with your movement when you’ve got a helmet on.

Finally, we also liked the additional option to add in chest and back protectors for an extra fee. If you like extra security while riding, this might be a worthwhile investment in your safety in case of an accident.


Our largest complaint stems from the jacket's performance in the waterproof tests. The fact that the outer layer becomes soaked so quickly is a major drawback. We understand that the thick polyester layer is there for safety reasons, but there could also have been some waterproofing on that outer layer.

Who Should Get The Alpinestars T-SP and Stella Gunner Jackets

This jacket is ideal for motorcyclists who aren’t fazed by the prospect of riding in wet conditions. The lack of waterproofing on the outer layer means that it's not a great option for people who don’t bike since they wouldn’t even be getting the outer layer’s safety benefits.

Final Verdict: Are The Alpinestars T-SP and Stella Gunner Jackets Waterproof?

The Alpinestars T-SP and Stella Gunner jackets will keep you dry on the road, even in very rainy conditions. So, in that most critical sense, the jacket is waterproof. However, if you can see yourself being bothered by wearing a jacket with an outer layer that soaks through quickly, you might want to look for one with internal and external waterproofing. The performance for these jackets was enough to land a spot on our best waterproof jacket list too!

Until next time, stay dry out there.