Disc Brake Details: Understanding Screw Sizes For Optimum Performance

bike disc brake screw size

Disc brake rotor bolts for bikes typically have a standard size of M5x10mm, with a T25 Torx head. The thread pitch for these bolts is usually either 0.8mm or 1mm, although 0.8mm is more common. It is important to use locktite or a similar thread-locking compound when installing these bolts, as they can vibrate loose while riding if not properly secured.

Characteristics Values
Bolt size M5x10mm
Bolt size (alternative) M6 x 18.7mm
Bolt type Socket head cap screws
Bolt material Titanium
Bolt material (alternative) Steel
Bolt weight 1.2g
Bolt colour Original Ti colour, rainbow colour
Bolt head type T25 Torx
Bolt thread pitch 0.8mm

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M5x10mm bolts for MTB disc brake rotors

M5x10mm bolts are commonly used for MTB disc brake rotors. They are available in a variety of materials, including titanium, steel, and Cr-Mo steel. These bolts typically come in packs of 6 or 12 and are compatible with a range of disc brake rotors, including Shimano, SRAM, and Magura.

M5x10mm titanium bolts for MTB disc brake rotors offer high performance, corrosion resistance, lightweight construction, and high strength. They are available in different colours, such as black, blue, green, gold, orange, red, and rainbow. These bolts usually weigh around 1.2 grams each and are often sold in packs of 6 or 12.

Steel M5x10mm bolts for MTB disc brake rotors are also a popular choice. They are made from high-quality alloy steel or stainless steel, providing durability and rust resistance. These bolts typically weigh around 1.83 grams each and are commonly sold in packs of 12.

Additionally, Cr-Mo steel M5x10mm bolts are another option for MTB disc brake rotors. They offer high strength and compatibility with various disc brake rotors, including Avid, Formula, Shimano, and SRAM. These bolts usually come in sets of 12 and weigh approximately 14 grams in total.

When purchasing M5x10mm bolts for MTB disc brake rotors, it is important to ensure that the correct torque is applied during installation to prevent damage or breakage of the bolts. The recommended torque value for disc brake rotor bolts is typically around 40 N·m.

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Shimano disc brake caliper bolts

On approximately five different models of Shimano disc brakes, the caliper fixing bolts are M6 x 18.7mm. These are socket head cap screws, which have a blunt end like a bolt but are technically screws as they screw into existing threads. This length of fixing bolt is suitable for 160mm rotors in a post-mount set-up. If you are using 180mm or 203mm rotors, you will need a longer caliper fixing bolt, approximately 40mm in length, to get through the caliper and the associated adapter.

You can purchase individual bolts for regular or flat mount calipers. The required bolt for flat mount calipers is determined by the chainstay thickness, not the actual bolt length.

When mounting your caliper, it is recommended to use blue Loctite 242 (a threadlocker) on the caliper fixing bolts and to tighten to a torque value range of 6-8 Newton-meters (50-73 inch-pounds).

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T25 torx head screws

When purchasing T25 torx head screws for disc brake rotor applications, it is important to consider the quality and weight of the screws. Well-made screws with tight tolerances can ensure accurate torque settings during installation. Additionally, titanium screws offer a lightweight option compared to steel or aluminium.

It is recommended to use thread locker blue (Loctite 242) on the caliper fixing bolts to prevent them from coming loose during rides. Properly torqued fasteners with thread locker will require human effort to loosen them. Regularly checking the tightness of the screws before each ride and rechecking with a torque wrench is also advised.

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M5 bolts with thread locker

When it comes to bike disc brake screw size, M5 bolts are a common size used for rotors. These bolts can be made from various materials, including steel, titanium, and Cr-Mo steel. They typically have a Torx T25 head and are available in different lengths, such as 10mm, 12mm, and 15mm.

To ensure the security of your bike disc brake screws and prevent them from vibrating loose, it is recommended to use thread locker compound, also known as thread lock or threadlock. This substance is applied to the threads of the bolt before tightening, and it helps to hold the bolt in place by creating a strong bond that can withstand vibrations.

When using M5 bolts with thread locker for your bike disc brakes, it is important to follow these steps:

  • Clean the threads of the bolt and the bolt holes to ensure that the thread locker can adhere properly.
  • Apply a small amount of thread locker compound to the threads of the bolt. A drop or two is usually sufficient.
  • Insert the bolt into the hole and tighten it to the specified torque with an Allen key.
  • Regularly check and retighten the bolts if necessary.

It is worth noting that thread locker compounds come in different strengths, and you should use a removable type like blue thread locker for disc brake bolts. Additionally, be cautious when applying thread locker to avoid getting it on the braking surface, as it can drip down.

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M5 bolts with 0.8mm thread pitch

Bike Disc Brake Screw Size

When it comes to bike disc brake screw size, specifically for M5 bolts with 0.8mm thread pitch, there are several important details to know. This type of bolt is commonly used for disc brake rotors and has specific measurements and characteristics that are essential for ensuring proper installation and function.

First, let's break down the bolt size designation of "M5." This indicates that the bolt has a diameter of 5mm, which is a standard size for disc brake applications. The diameter is measured at the shaft of the bolt, excluding the head. This measurement is crucial for ensuring the bolt fits securely within the designated space.

Next, the thread pitch of 0.8mm refers to the distance between the threads on the bolt. In the case of M5 bolts, the standard thread pitch is indeed 0.8mm. This measurement is important because it determines the compatibility of the bolt with the threaded hole or component it needs to engage with. An incorrect thread pitch can lead to improper fitment, excessive force required during installation, or damage to the threads.

When working with M5 bolts, it is recommended to use calipers and a thread checker for accurate measurements. While a metric ruler can be used in some cases, specialized tools provide greater precision. It is worth noting that the bolt length, which is measured from the end of the threads to the bottom of the bolt head, is also an important consideration to ensure the bolt is the appropriate size for the specific application.

Finally, when sourcing M5 bolts with 0.8mm thread pitch, they are often sold individually or in sets, depending on the specific application and manufacturer. It is important to verify the bolt specifications and ensure they match the requirements of your bike disc brake system.

Frequently asked questions

The standard size for disc brake rotor bolts is M5 with a T25 Torx head. The thread pitch is typically 0.8mm, but can also be found in 1mm.

The caliper fixing bolts for Shimano disc brakes are typically M6 x 18.7mm, with a socket head cap screw. For systems using 180 or 203mm rotors, a longer bolt of approximately 40mm is required.

The thread pitch for M5 bolts used to attach a disc brake rotor is typically 0.8mm, but it is recommended to check with a water bottle bolt to ensure compatibility.

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