3
J/105 Tuning Guide
Solutions for today’s sailors
Part 1: Rigging Preparation
The following recommendations are small
changes that should be made to the stock
J/105 to allow you to get the most from
your North Sails and make the boat easier
to sail and set up.
Head swivel shackle
The North Sails jibs come with a webbing
loop at the head. It is critical to have a
90-degree “twist” shackle to attach the
sail to the swivel. A standard shackle will
cause a hard spot at the top of the jib as
the sail is torqued.
Remove backstay toggle
Many J/105s come with a toggle that
rotates the hydraulic cylinder 90-degrees
so that the handle faces forward. While
it is nice to have the handle forward, this
toggle reduces the throw of the backstay
adjuster too much so that you are not
able to get enough tension in heavy air.
Some of the older boats actually need to
have the backstay rod shortened to get
enough backstay throw.
Change to 4:1 or 6:1 Cunningham
The standard Cunningham is 2:1 and
led aft to a cabinhouse halyard stopper.
This system should be replaced with the
lower purchase with integral cleating
shackled to the ring on the top of the
Quik Vang. This allows for easier and
more precise Cunningham control by a
forward crewmember. Many boats then
rig the asymmetrical tack line through the
free stopper.
Mark the tack line at the cleat
Put marks on the tack line at the proper
range of settings. As you approach the
windward mark you can then pre-set the
tack line so that when you extend the pole
and set the spinnaker the tack will be set
properly. The tack line is much easier to
work with in this placement than on the
side of the cabinhouse.
Fig. 1: Head “Twist” shackle
Fig. 2: 6:1 Cunningham
Fig. 1
Fig. 2