White Industries Eccentric Disk Brake Caliper Mount Adapter
This adapter exists because of a geometry problem that only appears on an eccentric hub. The ENO eccentric rear hub tensions the chain by moving the axle within the dropout - that is how a single-speed bike with vertical dropouts gets chain tension at all. But the disc rotor is bolted to the hub, so when the axle moves, the rotor moves with it, and the caliper, bolted to the frame, does not.
Design and construction
The adapter repositions the caliper to follow the rotor through the eccentric's range, so the pads stay centered on the disc instead of rubbing one side or running out of adjustment as the chain is tensioned. Without it you are choosing between correct chain tension and correct brake alignment.
Aluminum, about 50g. It is one of those parts nobody thinks about until the first time they tension the chain on an eccentric disc build and watch the rotor walk away from the pads.
White Industries machine in-house in Petaluma, California, and have since Doug White founded the company in 1978. For a component this size the benefit is unglamorous and real: consistent tolerances, a part that can be taken apart and put back together, and spares that still exist years after you bought it.
Fit and compatibility
For disc builds using the White Industries ENO eccentric rear hub. Frame mount standards vary, so tell us the frame and we will confirm the arrangement before you order.
Buying it from ProWheelBuilder
ProWheelBuilder is an independent wheel builder in Georgia. White Industries designs and manufactures this part; we stock it, we fit it to the wheels we build, and we are happy to talk through whether it is the right one before you buy.
Warranty
Manufacturer's warranty. White Industries warrants this product against defects in materials and workmanship. The duration, conditions and claim process are set by White Industries and can change without notice, so ask us and we will confirm the current terms before you buy.
ProWheelBuilder. Our own one-year warranty is a wheel warranty - it covers wheels we build, not tools or accessories. This item is covered by its manufacturer, as set out above.
Full terms are on our Policies & Warranty page.
Eccentric disc brake caliper mount adapter questions
Why does an eccentric hub need this at all?
Because the eccentric moves the axle - and therefore the rotor - relative to the frame. The caliper has to move the same amount or the brake goes out of alignment as you tension the chain.
Do I need it on a rim-brake build?
No. The problem is specific to a rotor bolted to a moving hub. Rim brakes act on the rim, which does not move relative to the frame when the eccentric turns.
Is ProWheelBuilder the manufacturer of the White Industries Eccentric Disk Brake Caliper Mount Adapter?
No. White Industries designs and manufactures it in Petaluma, California. ProWheelBuilder is an independent wheel builder in Georgia that stocks the part and fits it to the wheels we build.
Not sure? Text or leave a voicemail on 470-253-0929 or email info@prowheelbuilder.com — you will be talking to the people who build the wheels.
