Before hydration packs became the preferred method of carrying water and supplies, bikes had fittings for attaching water bottles. While bottle cages worked well on traditional diamond frames, cages became less practical as bicycle designs evolved over the years. When bikepacking and adventure riding became more popular, bottle cage fittings began reappearing on frames and even forks. Cool, right? Yup, until you wanted to use a frame bag and a bottle cage, or your frame was too small for high-capacity bottles. Thanks to Wolf Tooth Components’ B-RAD Double Bottle Adapter, you can satisfy your hydration and storage desires without resorting to hose clamps and duct tape.
Leveraging your bike’s existing braze-ons, Wolf Tooth’s Bottle Doubler ($23.95 MSRP) system lets you easily add or resposition frame-mounted accessories such as inflation devices or bottle cages. Weighing just 28 grams (sans hardware), the CNC-machined fittings bolt directly to your frame’s bottle cage bosses. The fittings utilize standard 5 x 0.8 mm threading, making them compatible with basically any frame-mounted accessory. Wolf Tooth supplies the necessary (stainless steel) mounting hardware, but you’ll need to provide the 4 mm hex key for installation.
Installing the Bottle Doubler is pretty straight forward. If you can install a regular bottle cage, you should have no trouble installing the Bottle Doubler. I tested the Wolf Tooth mounts on several different (steel) frames, and didn’t run into any compatiblity issues. Wolf Tooth recommends a maximum load of 1,700 grams for the Bottle Doubler, so take that into consideration when choosing accessories or bottle (cage) size. As with any component or accessory, you’ll want to check the bolts’ tightness after the first couple of rides (although I never experienced any loosening during my test period).
My Jeff Jones diamond frame bike is equipped with mounts for three bottle cages. One cage mounts on the under side of the down tube, and the other two cages are mounted on the upper side, one in front of the other. Since the under-side cage is reserved for my spares kit, that only leaves room for two small water bottles. Swapping the upper cage with Wolf Tooth’s adapter let me carry two large (750 ml) bottles with a third smaller (500 ml) bottle in the lower cage. Thanks to the Wolf Tooth’s offset design, accessing the two larger bottles proved easier than with conventionally mounted cages. And even with the two large bottles positioned near the head tube, I didn’t notice any adverse effects on the bike’s handling.
Is it safe to bolt more stuff on your bike’s frame? It depends. My testing was limited to steel frames with brazed-on fittings, and I made sure that I never exceeded the recommended 1,700-gram weight limit. It’s possible that the added weight might pose a problem on frames constructed from super-light tubing, but that’s not unique to Wolf Tooth’s system. When in doubt, contact your bike’s manufacturer to see if your frame can handle the stress of the added weight. I, personally, wouldn’t hesitate to use the Double Bottle Adapter to add room for a mini-pump or standard-size water bottle, but I wouldn’t rely on it (or any two-bolt cage) to hold two (full) 32-ounce Nalgene bottles.
Disclosure: Wolf Tooth provided review samples for this article, but offered no other form of compensation in exchange for editorial coverage.