Genoa Lead Block Systems

written by BoatUS

For optimum genoa performance in all wind conditions, you need to fine-tune your sail trim with a track and car system.

A complete system consists of track installed on the toerail, deck, or coaming, a pivoting wide sheave lead block and sliding car assembly to accommodate a changing lead angle, and a foot block to maintain the proper winch lead angle. By sliding the lead forward or aft, you control sail shape to make it luff evenly from head to tack. Moving the lead forward tightens the leach, loosens the foot, and makes the sail shape fuller and generally more powerful on a reach. Sliding the lead aft tightens the foot and allows the leach to twist off, which depowers the sail - a handy device in heavy air.

Adjustable lead cars use traveler car bodies that roll freely and can be moved easily under load. The most popular adjustable lead systems run fore-and-aft and result in minimal deck clutter. The trimmer adjusts the cars from the safety of the cockpit, simply by using a tackle system of control lines led aft. Secure adjusting tackle in a cleat or line stopper adequate to hold the car through any weather conditions and use low-stretch line or wire for the tackle to prevent it from stretching under load and automatically depowering with every puff of wind.

In addition to the added safety of operating from the cockpit, especially on short-handed cruising boats, you can "power up" the sail to improve your tacking performance. Before the tack, pull the lead slightly forward to increase drive in the genoa, and help you keep up your momentum through the tack. On the new tack, as the boat regains speed, ease the car slightly aft to flatten the sail and improve your boat's pointing ability.

Adjustable lead cars have another advantage for cruisers - readjusting the lead car after partially reefing a furling sail. As you reef, you can adjust the lead position while the sail is still being luffed. If you mark the proper predetermined reefing spot on the genoa and the track, this simple operation can be performed from the safety of the cockpit.