The Balance 580 is aggressively canvassed for its weight, with a quick, snappy motion best suited to day sailing.
Hull Speed
The theoretical displacement-mode speed limit — determined by waterline length, not engine or sail power.
A displacement hull pushes a bow wave whose speed is limited by the waterline length.
With a waterline of 58.3′, the Balance 580 tops out around 10.2 knots in displacement mode — after that, the bow wave outruns the hull and resistance climbs steeply.
1.34 × √58.3′ LWL = 10.2 kts
Performance Ratios
Racing handicap, sail-carrying power, stability and comfort — and what each one actually tells you about a day on the water.
SA / Displacement
32.8
Performance-oriented — carries a lot of canvas for its weight.
Displacement / Length
83
Ultralight — responsive and fast, but carries less stores.
Comfort Ratio
11.3
Quick, snappy motion — better for day sails and racing than long passages.
Capsize Screening
3.40
Above the 2.0 offshore threshold — best suited for coastal and protected waters.
SA/Disp (Calculated)
28.4
Computed from measured I/J/P/E rather than reported sail area.
Pounds/Inch Immersion
35lbs
Weight needed to sink the hull one inch — loading sensitivity.
Motion & Offshore Suitability
Two ratios that matter most when you're planning passages — how the boat feels in a seaway, and whether the hull geometry is suitable for open ocean.
Comfort Ratio
11.3
Quick, snappy motion — better for day sails and racing than long passages.
Under 20 — Snappy, racing motion
20–30 — Acceptable coastal
30–40 — Good offshore comfort
Over 40 — Very comfortable offshore
Capsize Screening Formula
3.40
Above the 2.0 offshore threshold — best suited for coastal and protected waters.
Under 2.0 — Acceptable for offshore
Over 2.0 — Coastal / protected waters
Estimated Speed by Wind
Rough boat speed estimates at different true wind speeds and points of sail — derived from hull speed, SA/D, and displacement, not measured polars.
| Point of Sail |
6 kts TWS |
10 kts TWS |
15 kts TWS |
20 kts TWS |
| Close-hauled40–50° |
4.8 |
6.1 |
6.8 |
7.1 |
| Close Reach60° |
5.8 |
7.4 |
8.2 |
8.6 |
| Beam Reach90° |
7.1 |
9.0 |
10.1 |
10.9 |
| Broad Reach120–135° |
6.6 |
8.3 |
9.3 |
10.1 |
| Run150–180° |
5.3 |
6.7 |
7.5 |
7.8 |
These are simplified estimates based on hull speed (10.2 kts),
SA/D (32.8), and empirical efficiency curves — not instrument-measured
polars. Real-world speed varies with sea state, bottom condition, sail trim, and current.
Speeds in gold approach hull speed;
bold gold means near or at hull speed.
Wind Range & Comfort Envelope
Estimated wind ranges for comfortable sailing on the Balance 580 — based on sail area, ballast, and displacement characteristics.
Ghost
Sweet Spot
Reef
Heavy
0–5 kts
5–16 kts
16–24 kts
24+ kts
Ghosting
0–5 kts
Light air, motor-sailing likely. Need patience and a light genoa.
Sweet Spot
5–16 kts
Comfortable under full sail. Best speed-to-comfort ratio.
Time to Reef
16–24 kts
Time to shorten sail. Reef the main, swap to a working jib.
Heavy Weather
24+ kts
Storm conditions. Storm jib or bare poles. Seek shelter if coastal.
How It Compares
Side-by-side with the boats most often cross-shopped against the Balance 580.
|
Balance 580 |
Bali 5 8 |
Lagoon 60 |
Oyster 565 |
Southerly 580 |
Voyage 590 |
| Dimensions |
| LOA |
58.3 |
57.9 |
59.9 |
59.4 |
58.2 |
58.1 |
| LWL |
58.3 |
— |
59.7 |
52.3 |
51.7 |
— |
| Beam |
28.2 |
29.7 |
32.4 |
16.8 |
17.1 |
28.4 |
| Displacement |
36 |
54 |
76 |
56 |
52 |
48 |
| Ballast |
— |
— |
— |
14 |
18 |
— |
| Sail Area |
2,255 |
1 |
2 |
1 |
2 |
— |
| Performance |
| SA/Disp |
32.8 |
21.4 |
21.4 |
19.3 |
24.1 |
— |
| Bal/Disp |
— |
— |
— |
— |
34.8 |
— |
| Comfort |
11.3 |
— |
— |
37.3 |
34.8 |
— |
| Capsize |
3.40 |
— |
— |
1.76 |
1.82 |
— |
| Hull Speed |
10.2 |
— |
— |
9.7 |
9.6 |
— |