What Size Spoke Wrench Do I Need

Preliminary Knowledge

Bicycle wheels rely on opposing tension from the spokes to suspend the rim around the hub. Each spoke acts as a skinny fastener, with the spoke existence the "commodities" and the nipple being the "nut."

Equally a nipple is turned and tightened, the spoke threads are drawn into the nipple, which increase the pulling or tension of the spoke. The process of adjusting spoke nipples and spoke tension is called "truing." By calculation the right amount of tension to the spokes, the wheel becomes strong and spins straight.

Nipples are commonly made of relatively soft materials such as brass or aluminum, both of which can exist easily damaged by the wrong sized spoke wrench. In that location are many different sizes and fifty-fifty shapes of spoke nipples, and having the correct wrench is important.

Top: gap between spoke nipple and oversized wrench; Bottom: correctly sized wrench on spoke nipple has no gap; — Top: an incorrectly fitting wrench that is too big. lesser: The right fitting wrench with amend appointment.

Square-Shaped Nipples

The mutual bicycle wheel uses a square-shaped nipple. The all-time method to determine the correct spoke wrench size is to utilise a caliper and measure out the nipple across the wrench flats.

Park Tool DC-1 Digital caliper measuring width of spoke nipple on silver bicycle wheel — Measure nipple size across the wrench flats

Information technology is important to know that the bore, or so called "gauge", of the spoke does not make up one's mind the spoke wrench size. For example, spokes that are 2mm in diameter (and then-called "14 gauge") will fit several dissimilar sized nipples and require different wrenches.

The table beneath lists a variety of square shaped nipple sizes, examples where they can be found, and the appropriate Park Tool wrench.

The Park Tool SW-7.2 spoke wrench is made with the three common spoke wrench sizes equal to the SW-0, SW-1 and SW-ii.

3.17mm to 3.24mm square

Typical examples include DT Swiss, Sapim, Wheelsmith, and others	SW-0, SW-9, or SW-7.2
3.26mm to 3.30mm square

Typical examples include older bicycles using 2mm spokes such as Union and Torrington spokes	SW-1 or SW-7.two
three.36 to 3.46mm square

Typical examples includes many value-priced bikes	SW-2, SW-9, or SW-7.2
3.95 to 4mm square

Typical examples include some Shimano® wheels, hub-driven e-bikes, Campagnolo® Scirocco, and heavy duty bikes with "10g spokes."	SW-three
3.70 to 3.75mm square

Shimano® standard three.75mm square	SW-14.five
4.2mm to four.3mm square

Shimano® standard four.3mm square	SW-14.five

Hex-Shaped Nipples

Hex-shaped nipples announced similar in shape to the common vi-sided nut. The Park Tool SW-11 is doubled sided, with ends to fit 5.5mm and 6mm hex-shaped nipples.

Examples of wheels using hex shaped nipples include some wheels from Fulcrum® and Campagnolo®. The 5.5mm side is for brass nipples. The 6mm side is for aluminum nipples.

Park Tool SW-11 Double-Ended Spoke Wrench being placed onto hex spoke nipple — Hex shaped nipple using a 6mm wrench

Internal Nipples

In that location are bike designs that place the nipple downwardly inside the rim where they are not attainable from the outside. It is necessary to remove the tire and rim strip to access the nipple.

Manufacturers vary in the size of fitting used for these Internal nipple rims. Information technology is often incommunicable to achieve down within the rim to measure the wrench flats. Contact the bike manufacturer for the size of the nipple.