Mounting Screw-On Fins (Older JetSurfs)

Guide

Mounting screw-on fins (older JetSurfs)

Difficulty: Beginner Time: ~15 min Applies to: Older boards Last updated: Sep 2026

Watch the walkthrough

Watch on YouTube ↗ · JETSURF USA — "JetSurf Tutorial 3: How to mount fins" (older tutorial). Timestamps below follow the video's on-screen counter (0:19–2:54).

This is the older screw-on fin system. If your board's side fins clip into FCS boxes instead of bolting into slots, use Mounting the fins instead. Both use a four-screw main-fin plate.

Tools

Phillips-head screwdriver (from the tool bag) — side fins
Allen key — main fin plate

Side fins

0:19 — Get the Phillips-head screwdriver from the tool bag and back the screws out of both side fins.
0:48 — Find the slots for the fins on the underside, towards the back, and seat a fin into each.
1:03 — Make sure each fin is fully seated in its slot.
1:09 — Hold the fin and drive its screw with the Phillips-head until it's completely secure. Repeat for the other side.

Main fin

1:39 — The main fin plate has a locating recess. Set the fin in with the slant facing the back of the board.
2:06 — Start all four screws with the Allen key — but don't run any of them fully in yet.
2:37 — With all four started, tighten them all down evenly.
2:54 — Check every screw is tight and both side fins are secure — then you're good to ride.

Tip: starting all four main-fin screws before tightening any lets the plate pull down square — tighten one fully first and the others can end up cross-threaded or the plate sits cocked.

Caution: the main fin only goes on one way — slant to the rear. Check all fin screws before every session; a screw-on fin that works loose on the water can be lost or damage the box.

Mounting screw-on fins (older JetSurfs)