Wolf Tooth B-RAD Mounting Base

Fits: Frames or forks with two standard bottle bosses at 64mm spacing; the B-RAD 3 also fits triple-bolt mounts. 1,700 gram max load per base.

The B-RAD base bolts to your bottle bosses and gives you a slotted rail to mount things on: a bottle cage moved up or down, a second cage, or a Wolf Tooth roll-top bag. It solves the frame bag problem, where the bag is in the way of the bottle, and the full-suspension problem, where the shock is.

Three lengths. B-RAD 2 moves a cage up to 54mm. B-RAD 3 has four threaded holes, up to 118mm of adjustment, and fits triple-bolt mounts on frames and forks. B-RAD 4 has nine threaded holes and 201mm of range, enough for two small bottles in line or a cage plus an accessory. The 3 and 4 include a foam pad and the zip ties Wolf Tooth says to use with them. 6061-T6 aluminum, 27, 41 and 75 grams, T25 Torx hardware included, 3 to 4 Nm, 1,700 gram max load per base. Needs two standard bosses at 64mm spacing. Made in the USA.

Which one: B-RAD 2 to shift one bottle clear of a frame bag. B-RAD 3 for a fork or triple mount. B-RAD 4 for bikepacking loads. If you run a front derailleur, Wolf Tooth notes you may need a spacer kit and longer bolts to clear the clamp.

Before you buy: buy the base together with the Wolf Tooth Morse Cage, or with the TekLite Roll-Top Bag in the mounting plate version; the plate is what attaches the bag to the rail.