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.
|
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.

Diagram Ref. |
Description |
Small Boat Part No. |
Midrange Part No. |
Big Boat Part No. |
A |
Backstay adjuster |
— |
-6 -10 |
-12 -17 |
|
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