Banks J-27 Tuning Guide

Mast Butt Location
Set the mast butt as far forward as possible. The mast should sit with no pre-bend. The rig is fairly bendy fore and aft and bends considerably with mainsheet tension alone, so we try to minimize this bend. This allows us to have a powerful mainsail in light air, but is easily flattened with backstay. Put blocks in front of the mast to push the mast against the back of the partners.
Centering the Rig
Raise a tape measure up the jib halyard and measure to both chain plates. With the lowers and intermediates slack, adjust the uppers until the measurements are even.

Shroud Tension
Use the 0-10 kt. setting as a base. Tighten from there. It is better to be too loose than too tight. Use these base settings on the shrouds. Use a Loos tension gauge to measure.


0-10 kts
10-15 kts
15+kts
Uppers
900 lbs
1200 lbs
1300 lbs
Lowers
900 lbs
1200 lbs
1400 lbs
Intermediates
hand tight
hand tight
hand tight


Headstay Length
Start with the headstay at maximum length (31' 6") '. Take turns to tighten as follows:
Shorten from max 1"above 18 knots

Backstav
With our rig setup and sail design, the backstay will control the shape of the main and the headsail in unison. Tensioning mainsail as well as tightening the headstay which flattens the genoa. In under 5 knots, when not a lot of mainsheet tension is little bit of back stay to get slight mastbend. Once the breeze gets to 5 knots you will want no backstay since increased main~ Sail with as little backstay as possible and use it to depower.

Mainsheet
In general, trim the mainsheet until the top batten is parallel with the boom. You can use the telltale at the top batten for this trim. The telltale should stall (go around the back of the sail) about 20%. As the breeze comes on, it will be hard to get enough mainsheet due to the bendiness of the mast. In over 15 knots, we have found that the tighter mainsheet you sail with, the higher you can point. A properly trimmed J/27 will almost never flog its main.

Genoa Trim
The J-27 loves to be sailed with a considerable amount of twist. For most conditions, we trim the genoa 6­-8" off of the top spreader. In light air the foot should be about 2" off the chain plates and 4" off the top spreader. In moderate breeze ease the lead aft so the foot touches the chain plates. As the breeze increases and you get overpowered, ease the lead aft some more to twist off the top more. At the top of the genoa you can twist as much as 12-18". If the main flogs excessively when you drop the traveler, you need more twist. The halyard should be tensioned to just remove all wrinkles in the luff in all conditions




Current Settings

0-10 kts
10-15 kts
15+kts
Uppers



Lowers



Intermediates