Nipple Driver

When building a wheel from components, the order of operations matters. Lace the wheel, seat the nipples through the rim, thread the spokes into the nipples (a few turns each), then drive every nipple to the same starting depth before any tension goes on the build. That last step; the “same starting depth” pass; is what the 1751/2 Nipple Driver does.

The tool's tip has a small nub machined into the end that engages the nipple's outer face. As you drive the nipple onto the spoke, the nub controls how far the nipple goes; when the nub reaches the rim, the nipple has been driven the same depth on every spoke in the wheel. That's the starting point for the tensioning pass.

Starting with all nipples at the same depth matters because uneven starting depths translate directly to uneven final tension. If half the wheel's nipples are 1 mm closer to the rim than the other half, half the spokes will run shorter than the rest at any given tension reading; the wheel will be impossible to dish without giving up tension balance, or impossible to balance without giving up dish. The 1751/2 closes that variability at the build's starting point.

A knurled handle gives good grip during the rapid in-out motion of seating nipples across 32 spokes in succession.

Compatibility

• Nipples: slot-head internal spoke nipples (the standard).
• Wheels: any standard nipple geometry; the 1751/2 is the depth-control tool, not a wrench.
• Companion tools: pair with a spoke wrench in the matching size for the tensioning pass.

Specs

• Tip: depth-control nub machined into the working end.
• Handle: knurled for grip.
• Length: sized for clearance through standard double-wall rims.

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 Nipple Driver is one of the small workshop tools that separates a methodical wheelbuilder from an improvising one: it's an extra two minutes per wheel that costs five minutes of search-and-fix work at the tensioning pass. Workshops that do this step routinely have noticeably more consistent wheels coming off their benches.

Pro tip from our mechanics

Drive every nipple in a single direction around the wheel; clockwise if you're right-handed, counter-clockwise if you're left-handed. The rhythm becomes muscle memory after the first wheel, and you stop missing nipples or double-driving them. The depth-control nub does the work; your job is to apply it consistently. The full wheel-building workflow is in How to true a bike wheel →