Master Shop Clamp

Heavy e-bikes changed what a workshop clamp has to do. A 25 kg full-suspension e-MTB clamped at the seatpost is moving an order of magnitude more mass than the road bikes the older clamp generation was sized for, and the jaw geometry that worked on a 7 kg road bike doesn't grip the same way under e-bike load. The Master Shop Clamp is our 2021 redesign for that load profile: shorter jaws, wider opening, and a simpler mechanism that drops the quick-release in exchange for the rigidity that a heavier bike demands.

The jaws are 5 cm (~2 inches) tall, which is short enough to bite securely on bikes with very little exposed seatpost: modern aero road frames, most full-suspension e-MTBs, and the trail-bike category that keeps shrinking seatpost exposure year over year. The jaws open to 110 mm, wide enough for the deepest aero seatpost shapes coming out of the wind-tunnel-shaped frame designs of the last few seasons. The replaceable rubber jaw covers (Unior 1693.11) carry over from our other clamp heads.

What's different from the Pro Shop Clamp

The Master Shop Clamp removed the quick-release button on purpose. The QR mechanism is a small reliability liability under heavy cycling load, and shops handling e-bikes care more about long-cycle reliability than they do about bike-to-bike swap speed. A road-focused shop running fast tune-ups and pad swaps is still better served by the Pro Shop Clamp 1693.1Q; an e-bike-heavy or DH-heavy workshop is the Master Shop Clamp's target.

Compatibility

The Master Shop Clamp drops onto the same column mount as the Pro Shop Clamp, so any 1693B, 1693C, 1693BS1, or BikeGator+ stand can upgrade to the Master Shop Clamp head without replacing the column.

Specs

• Article number: 1693.1M
• Jaw height: 5 cm (~2 inches)
• Jaw opening: 22–110 mm
• Mechanism: pressure handle only (no quick-release)
• Replaceable rubber jaw covers: Unior 1693.11
• Compatible with: 1693B, 1693C, 1693BS1, BikeGator+ family

Includes: clamp head with pre-installed rubber jaw covers, pressure handle.

Built in Zreče, Slovenia

Unior has been forging hand tools in Zreče since 1919, and is the official technical partner of multiple World Tour and downhill teams. The Master Shop Clamp's 2021 redesign came directly out of the working reality of heavy e-bikes coming off the factory truck and onto the bench. The jaw shortening and the opening widening were both decisions about which bike the clamp has to hold, and the e-bike question answered them.

Pro tip from our mechanics

The clamp-choice decision is the most consequential clamp-buying question we hear, and it isn't a one-clamp-fits-all answer. Where each clamp wins, broken down by workshop bike mix: How to choose a bike repair stand →