Backstay adjusters allow racers and cruisers to adjust and control mast rake and headstay tension. Adjusting the backstay shapes the main to optimize upwind and downwind performance. On racer/cruisers, tightening the backstay increases headstay tension for upwind sailing, while loosening the backstay offwind reduces weather helm. When selecting blocks or systems for backstays, make certain blocks match or exceed the wire or line breaking strength.

Typical Boat Length:
Small Boat: 22' - 28' (6.7 - 8.5 m)
Midrange: 29' - 34' (8.8 - 10.4 m)
Big Boat: 35' - 42' (10.7 - 12.8 m)

6:1 Right Angle This simple 6:1 system is used on small cruising boats with a single line or wire backstay. Diagram Ref. Description Small Boat Part No. Midrange Part No. Big Boat Part No. A Triple 344 2640     B Triple 347 2648

12:1 Cascaded This cascading 2:1/6:1 system provides a 12:1 purchase and is used on small racer/cruisers and daysailers. Diagram Ref. Description Small Boat Part No. Midrange Part No. Big Boat Part No. A Single 300     B Triple 344 2640     C Triple 347 2648

4:1 Split Backstay This 4:1 system is used on small keelboats with split backstay systems. Pinching the wires together tightens the backstay and increases headstay tension to flatten the genoa, decrease weather helm, and stabilize the rig in heavy air. Diagram Ref. Description Small Boat Part No. Midrange Part No. Big Boat Part No. A Single 304 304 308   B Fiddle 2655 2621 2621 1559   C Fiddle 2658 2624 2624 1556

8:1 Split Backstay A more powerful version of the split backstay adjuster uses a doubling wire running through a wire block for a purchase of 8:1. Diagram Ref. Description Small Boat Part No. Midrange Part No. Big Boat Part No. A Single 304 308   B Fiddle 2655 2621 2621 1559   C Fiddle 2658 2624 2624 1556

6:1 Double-ended Split This double-ended split backstay system leads lines forward to cam cleats mounted just ahead of the helmsman so adjustments can be made from either side of the boat. Diagram Ref. Description Small Boat Part No. Midrange Part No. Big Boat Part No. A Single 304 308 304 308   B Single 2636 2600   C Double 2638 2602   D Stand-up 349 2652 2652 2600 & 369     E Cheek 350 2644 2644 2606   F Cam cleat 468 150 150

Backstay Adjuster This adjuster is ideal for small racer/cruisers and daysailers. The handles fold down when not in use. Diagram Ref. Description Small Boat Part No. Midrange Part No. Big Boat Part No. A Backstay adjuster   B1722

Backstay Adjuster with Winch Handle This powerful backstay system operates without hydraulics. It is an excellent choice for larger racer/cruisers. The stay tensioner adjusts using a standard winch handle. Diagram Ref. Description Small Boat Part No. Midrange Part No. Big Boat Part No. A Backstay adjuster B500 B501 B502 B503 B Winch handle   B8AL B10AL B8AL B10AL

Backstay Adjuster with Winch Handle This 2:1 backstay adjuster is for boats with a split backstay. To rig, replace the two lower wires with a single wire and add a runner block at the top of the split. Size the block to match the breaking strength of the wire. Diagram Ref. Description Small Boat Part No. Midrange Part No. Big Boat Part No. A Runner  1991 3013 3013 3019 3024 B Backstay adjuster   B500 B501 B502 B503 C Winch handle   B8AL B10AL B8AL B10AL

Double-Acting Hydraulic Backstay Adjuster These powerful systems deliver oil when the handle is pushed and pulled, delivering oil twice as fast as single-acting pumps—an excellent choice for racer/cruisers.

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