CDP CLASSES:
CDP Home
Beneteau 36.7
Farr 40
J/105
J/109
Melges 32
M30
Swan 42
Swan 45

J/105 CDP:
Tuning Guide
Sail Descriptions
Client Testimonials
Class Rules

The Essentials

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.

Change to 6:1 Cunningham: The standard Cunningham is 2:1 and led aft to a cabinhouse halyard stopper. This system should be replaced with a 6:1 system 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. The tack line is much easier to work with in this placement than on the side of the cabinhouse.

Move mainsheet swivel base forward of the traveler: This allows for easier trim of the gross tune by the main trimmer, especially when tacking.

Tapered Spectra™ spinnaker sheets: These sheets have a light uncovered portion that attaches to the sail, with a covered portion that goes on the winch. The sheets should be 3/8" Spectra cored line with the cover removed at the sail end of the sheet. These lightweight sheets are used in all conditions and help downwind performance in light air. Heavy sheets pull down on the leech of the spinnaker in light air, closing the leech too much.

Mark tack line for spinnaker at cleat: Put marks on the tack line at the proper range of settings. As you approach the weather mark, you can preset the tack line so that when you extend the pole, the tack line will be set properly.

Also Recommended (but not essential)

Cross-sheet the Jib sheet: You can cross sheet the jib from the turning block up to the windward jib winch. With this system, the main trimmer can make small adjustments to the jib sheet as they are sitting right next to the jib winch. Tacking is a little tricky, so be sure to practice before trying this in a race!

Add twing lines for the spinnaker: Twing lines should be added to help control the lead position for the spinnaker. Twing lines are lines that allow you to pull down on the spinnaker sheet. To properly rig a twing set up, attach a block with a cleat (Harken part # 362 or alike) onto the stanchion base that is forward of the genoa and spin sheet turning block. The twing line with a small block (Holt Allen HA 1375 40mm snatch block) is run through the block/cleat on the stanchion base. The Holt Allen block is easily opened and removed from the sheet without having to re-rig the entire sheet. Tie a piece of shock cord to the becket at the top of the block/cleat and then up to the lifeline to keep it vertical when not loaded to avoid hitting the hull and deck and chipping the paint job. The spinnaker sheet should be led from the sail, through the twing block, and then to the turning block at the transom. The twing should be pulled on in very light air (almost drifting) and in heavy air when running as deep as possible. This is not a critical addition, but can help improve performance. This adjustment is not an all or nothing adjustment, but has a range through the entire adjustment. Trimmers should experiment with what works best through the wind range.

* Important note on twings - the down side to twings is that they add friction to the sheet, which is bad when jibing. It is a tradeoff between more sail shape control and better boathandling. Each crew should decide whether or not they like them. If you have trouble jibing with the twings, then you should go without them.