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Wolf Tooth Holiday Gift Guide

Wolf Tooth Holiday Gift Guide

Stumped on what to get your cycling-obsessed friends and family this holiday? We've compiled a list of products that should satisfy any type of rider, from clever on-the-bike tools and items to personalize and stylize their bikes, to Wolf Tooth hats and apparel.

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New 8-Bit Pack Pliers

New 8-Bit Pack Pliers

The new 8-Bit Pack Pliers is a lightweight multi-tool with 17 functions. Eight attachments nest inside the handles of master link pliers using magnets and a clever storage system. These attachments then fit into an 8mm ball detent swivel head that has a 4mm opening for hex bits, which adds functionality to the already-versatile master link pliers. This new multi-tool was created to solve almost any minor repair on MTB and road rides alike.


Each of the attachments can be swapped out and chosen for the task at hand. The hex bits include a spoke wrench and valve core wrench; a T10 and T25 Torx-compatible bit; flat head #3.5 and Phillips #2 screwdriver; and hex 2, 2.5, 3, 4, 5, and 6mm bits that fit into the ball detent swivel head that is also an 8mm hex bit. A magnet inside the swivel head keeps the bits in place while they are being used. The eighth bit is a rasp that can be used for clearing valve stems clogged with tire sealant. When the swivel head is angled, torque can be added to break loose a pedal or stubborn bolt. When the swivel head is unbent, the tool behaves like a screwdriver for faster rotations and quick work.


The master link pliers borrow functions from the popular Wolf Tooth Pack Pliers. The tips of the pliers can be used to remove and install the master link of a chain, while the pliers section closer to the bolt was shaped to the specifications for a valve stem lock nut. Storage space for one set of master links was built into the pliers handle with a magnet to keep them in place. The chainring bolt that holds everything together is available in a variety of colors.


The 8-Bit Pack Pliers is part of the Wolf Tooth Pack Tools product line. This is a line of tools that is designed to be lightweight and versatile enough to carry on a ride, while being just as strong and reliable as the tools on a workbench. Because that strength can be vital on the trail, we tested the 8mm swivel head function of the 8-Bit Pack Pliers to withstand more than 40 Nm of torque. Like other Pack Tools, this one was designed and machined with 7075-T6 aluminum at the Wolf Tooth machine shop in Minnesota. It will fit in a tool wrap or jersey pocket, or be a mainstay at any home workshop.

Find the new 8-Bit Pack Pliers here and wherever Wolf Tooth is sold.

1x Drivetrains Explained - Gearing, Mechanics, and Optimization

Wolf Tooth CAMO with elliptical chainring installed on bike
The simplicity and effectiveness of a 1x (pronounced "one-by") drivetrain, which refers to a single front chainring with multiple sprockets and a rear derailleur, has many people converting their multi-chainring setups.  At Wolf Tooth, we were at the forefront of this 1x revolution and wanted to share a summary of the most important points for 1x gearing, mechanics, and optimization.

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How to measure Bolt Circle Diameter (BCD)

How to measure Bolt Circle Diameter (BCD)

Bolt Circle Diameter (BCD) is the diameter of the circle that goes through the center of all of the bolts on your chainring. On bicycle chainrings this dimension is usually measured in millimeters. It is critical to know the BCD of your crankset when you are selecting a new chainring for your bike. In many cases the BCD is printed right on the chainring like in the example below.  Sometimes it is stamped or engraved on the back side of the chainring.

Three Wolf Tooth Chainrings

If it is not labeled on your chainring you will need to measure it. On a chainring with 4 bolts the BCD is the distance between two bolts across from each other. It can be somewhat difficult to make this measurement if you don't have a caliper since the crank arm gets in the way. The image below shows this measurement on a 104mm BCD chainring.

Caliper measuring distance between opposing bolts on chainring on bicycle

Alternatively you can measure the distance between two adjacent bolts and use the table below to determine the BCD. This is the easiest method to use for chainrings with five bolts.  Note that there are a few crank sets that have non-standard arm spacing. If this is the case then the distance between adjacent bolts will be different as you move around the chainring and standard chainrings will not fit.

4 Bolt Chainrings - Measuring 2 adjacent bolts

BCD        Distance (mm) Distance (in)
64mm 45.3mm 1.78in
76mm - asymmetrical 49.0mm; 62.4mm; 53.9mm 1.93in, 2.45in; 2.12in
88mm 62.2mm 2.45in
94mm 66.5mm 2.62in
96mm - symmetrical 67.9mm 2.67in
96mm - asymmetrical
55.2mm; 78.8mm 2.17in; 3.10in
102mm 72.1mm 2.84in
104mm 73.5mm 2.90in
110mm Shimano - asymmetrical 63.6mm; 90.6mm 2.50in; 3.56in
110mm SRAM - asymmetrical
64.8mm; 89.3mm 2.55in; 2.51in
120m 84.9mm 3.34in


5 Bolt Chainrings - Measuring 2 adjacent bolts

BCD Distance (mm) Distance (in)
94mm 55.2mm 2.18in
110mm 64.7mm 2.55in
130mm 76.4mm  3.01in


A caliper measuring the distance between two adjacent bolts on a chainring on a bicycle

The equation for the BCD for any symmetric bolt pattern is given by:  BCD = d / sin(180/n)

where d is the center to center distance between adjacent bolts, n is the number of bolts, and the angle is in degrees.

BCD Guide

Another method is to remove the chainring from your bike and place it on a printout of the BCD guide in the link below. Make sure to print it out in the actual size with no scaling. Then just find the circle pattern that lines up with the holes on your chainring. 

Measure BCD Bolt Circle Diameter



 There are always exceptions.  Be aware of a few specific examples:

  • For SRAM X7 (new version), X9, XO, XO1, XX1 our solution is the direct mount rings. These rings on these cranksets are 94 BCD. With our direct mount solution you remove the original chainring and spider and replace it with our ring that interfaces directly with the splines on the crankset. You will need a T25 Torx L-wrench to remove the three bolts that secure the chainring to the crankarm.
Backside of a direct mount chainring installed on bicycle cranks
  • SRAM Red Exogram has a hidden bolt that screws into the crank arm. The chainring bolt may be too long to firmly secure the chainring so you will need to add a washer (see photo) or carefully file down a bolt to the proper length.
SRAM Red Exogram bicycle cranks and chainring                 Hidden chainring bolt on SRAM Exogram cranks
  • 11 speed Shimano (so far DuraAce and Ultegra) has a non standard arm spacing. We do not currently offer a solution for this application.

Direct Mount Crank Interface

Chainring Diameter

Some bicycle frames have an upper limit for the maximum chainring size you can use due to clearance between the chainring and chainstay. We created a separate page with information on Chainring Diameter by Tooth Count that will help you determine how large of chainring will fit on your bike.