Chin Mount for O’Neal Sierra 2 — Compatible with GoPro, DJI, Insta360 & other action cameras

This is a summary. The complete and binding version is the Installation & Safety Guide (PDF). Read it in full before installing. The steps are also shown in the online installation guide, with a video.

Before installation

• Make sure you received the chin mount model intended for your helmet.
• Test the mount position on the helmet before removing the adhesive protective film.
• The installation area must be clean, dry and free from grease, wax, silicone or other products that may reduce adhesion.
• Do not start installation if the mount does not sit correctly on the helmet geometry or if you notice deformation or damage.

Installing the mount

1. Identify the correct area of the helmet and check the position and orientation again before bonding.
2. Clean the installation area with the supplied alcohol wipe and allow the surface to dry completely.
3. Gently warm the helmet installation area and the adhesive tape on the mount. Bond while the surfaces are slightly warm.
4. Remove the red protective film without touching the adhesive and position the mount correctly on the helmet.
5. Press the mount firmly against the helmet for approximately 1–2 minutes, with even pressure across the entire contact area.
6. Do not use the mount for 24–72 hours after installation. The adhesive reaches maximum bonding strength after approximately 72 hours at 20 °C.

Correct heating: use only a standard household hair dryer, held approximately 10 cm / 4 in from the mount. Warm the adhesive for approximately 10–15 seconds, keeping the airflow moving, until the tape and the surface are slightly warm, not hot. Do not use a heat gun, an industrial hair dryer or any other high-intensity heat source: the mount is made of plastic and can soften, deform or be permanently damaged. If the mount becomes very hot, begins to soften or changes shape, stop heating immediately and let it cool.

Do not try to speed up adhesive curing by strongly or continuously heating the mount after installation. After pressing, let the adhesive stabilise for the recommended period.

After installation

• Visually confirm that the mount is seated correctly and shows no deformation.
• Do not pull, twist or load the mount during the initial adhesive stabilisation period.
• Install the camera only after the waiting period has been observed.

Fitting the safety tether

1. Stick the tether's adhesive base directly on the helmet shell, on a rigid area separate from the chin mount, so that the tether is anchored independently of the mount. Do not stick it on the visor, on the chin mount, on rubber trims, on vents or on any other moving part.
2. Prepare the area as for the mount: clean it with alcohol, let it dry and warm it gently, with the hair dryer only.
3. Stick the base, press firmly and evenly, and observe the same 24–72 hour waiting period before use.
4. Attach the other end of the cable to the camera if it has a tether point. If it does not, attach it as close to the camera as possible, to the clamp or frame the camera sits in.
5. Leave the cable slightly slack so that it does not pull on the camera in normal use. Check that it does not enter your field of view, does not block the visor and, on modular helmets, does not prevent the chin bar from opening.

The role of the safety tether: the tether is extra security for the camera: it keeps the camera attached to the helmet even in an impact or an unexpected detachment. If that happens, stop safely as soon as you can and do not try to recover the camera while riding. After such an event, check the tether and its base and replace them if they have been loaded or damaged.

Check before every use

• Visually inspect the mount for cracks, deformation, damage or play.
• Inspect the adhesive edges; there must be no lifting or detached areas.
• Apply moderate manual force to the mount to confirm that it is firmly attached to the helmet.
• Check that the camera is secured in the mounting system and that the fastening element is properly tightened.
• Check the safety tether, its adhesive base and its attachment to the camera.
• Repeat the inspection after an impact, a dropped helmet, unusual heat exposure or any event that may have affected the mount or adhesive.

Use and maintenance

• Do not use the product if it is cracked, deformed, partly detached or damaged.
• Clean the product with a soft cloth. Do not use solvents or aggressive chemicals.
• Do not modify the product by drilling, cutting, sanding or any other operation that could affect its geometry or strength.
• The mount is made of PETG, which can soften or deform under excessive heat. Avoid intense heat sources and stop using the product if it shows deformation after exposure to high temperatures.

Essential warnings

• Use only the chin mount model intended for your helmet.
• Do not use the mount if the adhesive shows any separation.
• Do not use a heat gun or industrial equipment for installation.
• Check that the mount, the camera and the safety tether are secure before every use.
• The product, including the safety tether, is not protective equipment and offers no protection in an impact or accident.

User responsibility

Mounts3D products are 3D-printed accessories intended exclusively for mounting action cameras. In accordance with Regulation (EU) 2023/988 on general product safety, they are designed and manufactured for use under normal and reasonably foreseeable conditions, following the instructions provided. They are not personal protective equipment (PPE) within the meaning of Regulation (EU) 2016/425.

The user is responsible for correct installation, for checking the attachment and for the suitability of the product before every use. Improper use, modification of the product, installation contrary to the instructions or use outside the intended purpose may lead to product failure or loss of the camera.