To order a Harken Asymmetric Reflex Furler, size the drive unit to your boat's length and sail area, then measure your Full Hoist (FH) dimension to select a kit with a torsion cable longer than that measurement. Each complete system arrives with everything needed to furl one asymmetric spinnaker, gennaker, or cruising spinnaker, and additional sails share the same unit through a quick-release T-slot.
Harken Reflex asymmetric furlers at a glance
| Unit | Typical boat length | Furling line diameter | Primary use |
|---|---|---|---|
| Unit 1 | 35–40 ft (10.6–12.0 m) | 1/4 in (6 mm) | Asymmetric / cruising spinnakers & gennakers |
| Unit 2 | 50–60 ft (15.2–18.3 m) | 5/16 in (8 mm) | Larger free-flying sails |
| Unit 3 | 44–58 ft (13.4–17.7 m) | 3/8 in (10 mm) | High-load / long-luff sails |
Loads run higher when the same unit is used for code zero sails, so the maximum boat length and sail area shrink accordingly — always check the "Typical Boat Length" and "Maximum Sail Area" figures on the unit page.
What comes in a complete Reflex asymmetric system?
The Reflex furling system for asymmetric spinnakers includes every part needed for one sail: one drive unit with a snap shackle attachment, a tack swivel, a head swivel, a torsion cable, and a set of cable clamps. For each additional sail you want to furl on the same unit, order a separate tack swivel, head swivel, Reflex torsion cable, and set of cable clamps — the quick-release T-slot then lets you swap furled sails in minutes.
What does my boat need before installing one?
Two things are required on the boat: a spinnaker halyard, and an attachment bail or adjustable tack fitting on a bowsprit or bow extension. The tack fitting must position the furler so the drive unit clears both the forestay and the bow pulpit when the sail is set and furled.
How do I determine the correct torsion cable length?
Every system includes a length of Reflex torsion cable, and choosing the right cable is the key ordering decision. Measure your Full Hoist (FH) dimension — the distance between the sail attachment points at the top of the rig and the bow fitting or fully-extended bowsprit. Select a kit whose cable length exceeds your FH measurement so the sail flies at full hoist with cable to spare.
How do I attach the furler and rig the furling line?
The standard asymmetric system ships with a threaded snap shackle adapter. To switch to a high-resistance D shackle or a soft-attach 2:1 adjuster, order the matching part for your unit:
| Unit | High-resistance D shackle | Soft-attach 2:1 adapter |
|---|---|---|
| 1 | 7351.21 | 7351.22 |
| 2 | 7352.21 | 7352.22 |
| 3 | 7353.21 | 7353.55 |
The system uses a continuous furling line. Talk to your rigger about a construction with a structural cover over a nonstructural core, and have the rigger capture the aft block in the loop before splicing — once spliced, the furling line loop can be loaded into the stanchion leads and drive unit. Size the line by unit (1/4 in / 6 mm for Unit 1, 5/16 in / 8 mm for Unit 2, 3/8 in / 10 mm for Unit 3). For loop length, cruisers measure from the furler to the aft lead block in the cockpit; racers use the J dimension plus the bowsprit length minus 60 cm (2 ft). Double the loop length and add enough for the overlap in the end-for-end splice.
Frequently asked questions
What sails is the Harken Asymmetric Reflex Furler designed for?
It is built for asymmetric free-flying spinnakers, cruising spinnakers, and gennakers with a loose, positive luff longer than the leech.
How do I choose between Unit 1, 2, and 3?
Match the unit to your boat length and maximum sail area using the figures on each unit page. Remember that using the system for code zero sails raises loads, reducing the maximum boat length and sail area the unit can handle.
What measurement do I need before ordering?
Your Full Hoist (FH) dimension — the distance from the sail's top attachment point to the bow fitting or extended bowsprit. Choose a kit with a torsion cable longer than this figure.
Can I furl more than one sail on the same unit?
Yes. The quick-release T-slot lets you switch sails, provided you order a separate tack swivel, head swivel, Reflex torsion cable, and cable clamps for each additional sail.
What furling line should I use?
A continuous line with a structural cover over a nonstructural core, sized 1/4 in (6 mm), 5/16 in (8 mm), or 3/8 in (10 mm) for Units 1, 2, and 3 respectively.
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