We know what you’re thinking – “A Chromag bike that isn’t made of Chromoly??” Steel isn’t going anywhere as our flagship material, with titanium appearing on some ultra-premium models. That being said, Aluminum was the best choice for the Minor Threat for a couple of reasons.
Firstly, the use of aluminum allows us to make a bike that’s burly enough to hold up to the bike park without being too heavy for a lighter rider to manage. Aluminum has a lower strength-to-weight ratio than steel, meaning that more volume of aluminum is required to make a frame that holds up to our strength standards. This is why you’ll notice that the tubing used in the construction of the Minor Threat is thicker than that used on most of our steel frames. With this in mind, it might follow that an aluminum bike and a steel bike that have exactly the same mass would have the same strength. This is not quite the case due to some more complicated physical principles involved in the shape and size of the different tubing (like the second moment of area, if you want to really go down the rabbit hole), that mean you can often make an aluminum frame slightly lighter than a steel one without compromising strength.
Another one is that aluminum is pretty low-maintenance. As you probably know all too well if you own one of our other frames, it’s very important with chromoly to grease your seatpost every couple months. If water gets into an ungreased steel seat tube, it will corrode the steel and form a bond with the aluminum of your seatpost, making it nearly impossible to remove. However, this isn’t an issue with an aluminum bike. While unpainted steel is not naturally corrosion-resistant, aluminum is! The secret is aluminum oxide, a chemical compound that forms when aluminum is exposed to air and creates a thin film on unpainted sections of your frame. This film is what keeps aluminum from rusting. So while you should still grease your seatpost (and pretty much every component-to-component interface for that matter) with an aluminum bike, it’s a little more forgiving to being “ridden hard and put away wet”.
Just like the rest of our Taiwanese-made frames like the Rootdown, Stylus, and Monk, the Minor Threat is handmade by a team of highly skilled framebuilders in Taiwan, and is held to the same stringent quality control standard that our frames are known for.