This 4:1 mainsheet system combines the 40 mm Carbo Ratchet with a high-strength Carbo Fiddle block
Harken has developed a 4:1 mainsheet system for dinghies and beachcats like the Hobie Wave 13 that use our 40 mm double switchable Carbo Ratchet. We combined the low profile of a side-by-side double with a lightweight, high-strength Carbo Fiddle block.
The challenge was to develop a “balanced” minimal friction system. Balance and reduced friction is achieved when the last lead exits the sheave on the block's centerline and aligns to the line falls as they travel past one another through the block and tackle. You can enhance reeving efficiency by using a tapered mainsheet to spread the falls in the tackle further apart.
Our Hobie Wave mainsheet system uses a HSB411, 40mm side-by-side double Carbo Ratchet (two sheaves on the same axle centerline) in the clew of the main and a 2657, 40 mm two-sheave Carbo Fiddle (one sheave is located vertically above the other), with a 281 Micro stainless steel eyestrap (mounted between the cam and cam arm supports) to deadend the mainsheet.
Using a side-by-side double Carbo Ratchet in the clew instead of a fiddle and mounting a fiddle without a becket on the traveler car, reduces the stack height of the mainsheet blocks by 1.5" (38 mm). This allows more mast rake which translates into better upwind performance.
This system became legal when the International Wave Class Association dropped the mainsheet system stack height rule. Accomplished Hobie Wave sailor John Williams said, “You made a lot of us happy because the HSB411 allows us to rake the mast more and at the same time get away from larger, longer fiddles. You killed two birds with one block!”
Hobie website: http://www.hobiecat.com