In this article I’m going to explain how to correctly install this Shimano Bike Brake Booster I was lucky enough to accidentally find online.
Although a bit more exotic, they fall into the same category as bar extensions in terms of being a decidedly ’90s tech upgrade for mountain bikes.

Apparently they were indeed used on competition bikes, Missy Giova’s Yeti Arc being a prime example here. The brake booster on display is a DKG brake booster.
In general, original vintage bike brake boosters are quite rare to obtain and I’ve never seen one on any of the marketplace listings.
A brake booster prevents the flex that occurs in the brake bosses when the spinning rim forces the brake pads to move forward and outward.
The bike brake booster keeps the bosses in place, which in turn increases the brake performance and lowers the risk of brake pad squealing.

Unlike more traditional brake boosters this Shimano version is made from carbon, which lends it that bit of vintage pizzazz.

To accommodate for the extra room a custom pair of longer hex bolts with washers are part of the package. The thick washer is meant to maintain enough space between the v-brakes and the brake booster itself.

I did a quick polishing step in between to remove any of the discoloration that had happened in two decades.
Video Tutorial
Installing the bike brake booster
Installing the brake booster is a piece of cake when you know in what order to place the various washers.
The simple washers go on each side of the brake booster, with the thicker washer between the brake booster and brake. The washer with the small extension sits onto the brake pivot.

The end result looks awesome. Now I only need to find an extra one for the rear.