Boat Trailer 6″ Red Poly Self-Centring Keel Roller with Galvanised Standard Bracket & Clamp Kit – 17mm Bore (SKU: BDA040)

The BDA040 is a 6″ red poly self-centring keel roller designed to automatically guide your boat’s keel into the correct position during launch and retrieval.
This roller features tapered outer edges that gently nudge the boat toward the centre line, reducing sway and misalignment—especially useful on windy days or uneven ramps.

Crafted from soft yet durable red polyurethane, the roller provides non-marking, UV-stable protection for fibreglass hulls. Its 17mm bore fits snugly on standard 16mm trailer spindles.

The included galvanised steel bracket and 75x50mm clamp-on stem adjusters allow for flexible, weld-free installation—making upgrades and replacements a breeze.

Specifications:

Perfect for boaters who want effortless alignment and added hull protection, BDA040 keeps your keel where it belongs—right down the centre.

Frequently Asked Questions

• What does “self-centring” mean?
  The roller is tapered at both ends to automatically guide the boat’s keel toward the centre of the trailer as it rolls.
• Is this better than a flat roller?
  Yes, especially for people launching solo or in windy/ramp-challenging conditions.
• Will it fit a 16mm spindle?
  Perfectly! It has a 17mm bore made to fit standard 16mm shafts.
• Is installation hard?
  Nope. Clamp-on bracket means you can skip welding—just bolt it in.

Is This the Right Kit for You?

Recommended For:

• Fibreglass boat owners looking for automatic keel alignment
• Solo boaters or those using steep or uneven ramps
• Anyone replacing flat or Sydney-style rollers with more control
• DIY installers who want flexible mounting (clamp-on)

Not Recommended For:

• Boats with flat hulls or very wide keel surfaces
• Heavy-duty trailers needing 8″ or industrial-grade support

Installation Tips:

1. Mount the bracket to your trailer’s keel rail using the 75x50mm clamp-on stem adjusters.
2. Slide the roller onto your 16mm shaft through the 17mm bore.
3. Position and centre the roller using spacers if needed, then lock the spindle ends.
4. Ensure smooth spin and side-to-side guiding motion before use.