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 2640  —  — B Triple 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  —  — C Triple 347  —  —

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 304 308  — B Fiddle 2621 2621  — C Fiddle 2624 2624  —

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  — C Fiddle 2658 2624  —

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 300 304  — B Single 340 2600  — C Double 342 2602  — D Stand-up 349 2652  — E Cheek 350 2644  — F Cam cleat 150 150  —

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