Spoke Wrench, 5 x 5.5mm

The 1636/2P is the double-sided spoke wrench for the largest two nipple sizes in the standard cycling-tool range: 5.0 mm and 5.5 mm. These are sizes you'll see on heavy-duty wheels, some commercial-use builds (cargo bikes, e-bikes with high-torque drives, fat bikes with very heavy spokes), and older European builds that pre-date the modern 3.3/3.45 mm convention.

The combination-wrench form factor is the same as the other double-sided wrenches in the line (3.3/3.45, 4.0/4.4, 4.3/4.4), but the 5.0 and 5.5 mm sizes are large enough that the wrench body itself is bigger and the working faces have more material. Wheels at this nipple size carry more spoke load, and the wrench needs to transmit more torque without flexing.

For most workshops, this isn't an everyday-use tool; most builds don't reach into the 5.0 mm or 5.5 mm range. But for the shop that services e-bikes, cargo bikes, or older heavy-duty wheels, the 1636/2P is the wrench that fits the nipples those wheels actually use. Stock it on the back shelf and pull it out when one of those wheels comes in.

Compatibility

• Nipple sizes: 5.0 mm (one side), 5.5 mm (other side).
• Engagement: four-flat on both sides.
• Wheels: heavy-duty wheels, cargo bikes, some e-bikes with high-torque drive systems, fat bikes, older European builds.

Specs

• Two nipple sizes on a single combination-wrench body.
• Plastic-dipped handle for grip.
• Larger working faces sized for the higher-torque loads of larger nipples.

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 5.0/5.5 mm wrench is the high-end-load workshop tool; the wrench that earns its keep on the wheels carrying the most weight, the highest motor torque, or the largest spokes. Workshops servicing the heavier-end of the wheel market keep one on the back shelf; for most builds the 3.3/3.45 mm and 4.0/4.4 mm variants are the everyday tools, with this one as the heavier-load specialist.

Pro tip from our mechanics

5.0 and 5.5 mm nipples in modern wheelsets are almost always on bikes with cargo or motor loads; the spoke load comes from the bike's intended use, not from the rider's weight. When servicing these wheels, the manufacturer's published tension spec is the right target rather than a feel-it-out-by-comparison number; pull up the wheelset's published spec sheet (or the wheel manufacturer's service documentation) before tensioning. The full wheel-truing workflow is in How to true a bike wheel →