Lewmar's Synchro footblocks use alloy cheeks, fixing isolators and to prevent sealant from getting into the sheave, a moulded base plate. Synchro blocks combine geometry, sheave ratios and a unique Free Spin bearing to deliver performance that’s comparable to ball and roller bearing blocks used in racing, but at a more affordable price. With conventional blocks, one of the biggest losses in efficiency comes from the distortion of line as it wraps around the sheave. Synchro blocks provide the optimal ratio between line size, sheave diameter and the interface between rope and sheave. The result is larger sheaves with a smaller axle than exist on conventional blocks. Synchro blocks improve efficiency by nearly 5% on a single block at a load of 442lb. Calculated over a typical six-block mainsheet system, this approaches a 40% improvement over conventional blocks.
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