Practical Sailorvideo
Sailboat Backstay Adjustment for Beginners
10 October 2026 · 9 min · 78K views
What this video covers
Adjusting the backstay controls mast bend, forestay sag, and sail shape to manage heel, weather helm, and pointing ability.0:17 Tightening the backstay increases forestay tension to flatten the headsail and bows the mast forward to flatten the mainsail, which depowers the rig.1:01 Easing the backstay increases forestay sag and mainsail depth, adding power for light air or downwind sailing.4:45 Because rig geometry varies significantly between masthead and fractional rigs, sailors must consult the boat or rig manufacturer’s tuning guide to establish safe minimum and maximum tension limits.2:42 Selden provides specific guidance on breaking loads for various configurations, which serves as a reference for setting these limits.3:05 Once established, mark these settings on the adjuster or control line.3:27 When adjusting, monitor the forestay for sag, the mainsail for overbend wrinkles, and the helm for balance.3:53 Always re-trim the mainsheet, vang, and halyard or Cunningham after changing backstay tension to maintain desired sail twist and draft position.6:59
More from Practical Sailor
From Practical Sailor — see the channel’s boat, crew, and every analysed video.
The Sailing Directory Newsletter
One email with the fleet's best finds — the moments, boats, and stories worth your watch time. Enter your own address to get your own copy.