Posted: Jul 19, 2010 - 02:42 PM
Likely due to the longer and larger diameter shrouds and forestay required. Not sure if they are included but the 18 requires diamond wires for the mast also where the 16 doesn't.
Regards,
Dave
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Dave Bonin
1981 Nacra 5.2 "Lucile"
1986 Nacra 5.7 "Belle"
Winnipeg, Manitoba, Canada
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