Choosing the correct bolt length for your Gen2 or Gen2.5 Foil Drive installation is essential for safe, secure mounting and protecting your equipment.

Bolts that are too short may not provide sufficient thread engagement, while bolts that are too long can bottom out or potentially damage the mast or internal components.

This guide explains how to measure the correct bolt length for your specific board and mast configuration.

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Why Correct Bolt Length Matters

Using the correct bolt length ensures:

• Secure and stable mast installation
• Proper clamping force between the mast, board and electronics box
• Adequate thread engagement
• Reduced risk of damage to internal components
• Reduced risk of mechanical failure while riding

 Important: The bolt must engage the threads correctly without being too short or bottoming out before the components are securely clamped.

How to Measure Your Bolt Length

The correct bolt length can vary depending on your board, mast and installation configuration. Rather than relying only on a standard bolt length, use the Foil Drive Driver Tool to determine the correct length for your setup.

1. Assemble Your Foil Drive

Set up your Foil Drive exactly as it will be used on the water.

Include:

• Foil Drive electronics box
• Mast
• Board
• External Patch Antenna, if applicable

Make sure all components are positioned correctly before measuring.

2. Insert the Foil Drive Driver Tool

Insert the Foil Drive Driver Tool into the bolt hole in the electronics box.

The driver should be positioned at the same depth as the bolt will sit when installed.

3. Mark the Measurement Point

Place your fingertip on the driver where it meets the top surface of the electronics box.

Your fingertip marks the reference point for measuring the required bolt length.

4. Compare Your Bolt

Hold the bolt alongside the driver and align the bolt head with your fingertip/reference point.

Compare the length of the bolt against the driver to determine whether it is suitable for your particular installation.

The measurement should account for the full clamping stack of your board, mast and Foil Drive components.

Confirm the Bolt Is Correct

Once you have selected the bolt, install it and check that:

• The bolt engages the threads smoothly.
• The bolt provides sufficient thread engagement.
• The mast and electronics box clamp securely.
• There is no movement between the components.
• The bolt does not bottom out before the components are securely clamped.
• The bolt does not require excessive force to tighten.

Never force a bolt into position. If the bolt reaches the end of its travel before the components are securely clamped, it may be too long and could cause damage.

Before Every Session

Before riding, check that:

• All mounting bolts are the correct length.
• All bolts are correctly installed and securely tightened.
• The mast and electronics box are firmly clamped.
• There is no movement between the components.

It is also good practice to re-check bolt tightness after initial assembly and periodically throughout your session or riding day.

Important Safety Information

Using an incorrect bolt length can result in inadequate clamping, equipment damage or failure during use.

Always measure and confirm the correct bolt length for your specific Gen2 or Gen2.5 configuration before riding.

If you are unsure whether your bolts are the correct length, do not ride until the installation has been checked. Contact Foil Drive Support if you need assistance.