Harken 7411.11 1/2 MKIV Jib Reefing & Furling - Manual (Page 38)

Operation Halyards/Headstay Tension
Backstay Adjusters
Backstay adjusters allow headstay tension to be varied to change sail shape to match
conditions. They permit a very tight headstay to be eased when boat is not in use.
For best performance, consider adding a backstay adjuster; either a block and tackle,
a mechanical adjuster like those offered by Harken, or a hydraulic adjuster.
Remember to keep headstay tight for best performance when furling or reefing.
If your boat is fitted with an adjuster be sure that it is tensioned before the
halyard is tensioned. If not, backstay adjuster may increase halyard tension
and could damage the sail or furling system.
Racing boats often slack the headstay completely when sailing downwind.
Check to be sure that foil does not jam against upper headstay terminal when
backstay is released. To prevent this, it may be necessary to shorten foil slightly.
38 MKIV Underdeck Unit 1, 2, 3
On many boats it will not be possible to attach spinnaker
halyard to bow pulpit or it may be "sucked" into jib when
furling.
On some boats the spinnaker halyard lays across
headstay and will catch on halyard swivel, foils or
jib halyard. To prevent problems it may be necessary
to install a masthead bail to move spinnaker halyard
block forward and to one side.
Boats with external halyards may find it necessary to
flip both ends of spinnaker halyard behind spreaders
to prevent fouling with furling system.
Headstay Tension
A furling system will work best if headstay is tight.
A loose headstay is difficult to rotate and can cause
unusual wear on foil joints.
To adjust headstay tension, remove sail and furling line
from unit and follow instructions on page 30.
Tip: Before adjusting headstay tension, slack
mainsheet and vang.
Spinnaker Halyards
Spinnaker halyards occasionally cause problems
with furling.
WARNING! In severe cases, spinnaker halyards
can jam furler causing loss of control of boat
which can cause an accident, damage to your
vessel, personal injury or death. See www.
harken.com/manuals for additional safety
information.