I'm looking at a '73 Hobie 16 around the corner. The owner says it has the "desirable big hulls" and that they were smaller later on. Is that true? I thought they all were the same exept for small weight variations.
AFAIK H16 hulls were always the same size, although in 1985 they were lighter. 
only in '85? I've never heard about that.
I thought '83 and later weighed 10 pounds lighter.
Most '84's and '85's were up to 30 lbs lighter. The class minimum weight was reduced from 340 lbs to 320 lbs in 1985 (where it is today).
I owned an '84 that weighed 315.
The lighter boats are easily identified by a red hull/deck glue seam.
The boats proved to be fragile at that weight, so the weight started to creep up as Hobie beefed up the structure. In the mid-90's, they refined their manufacturing techniques and were producing boats that were closer to minimum. They are still doing so today.
My 1998 weighs 320 - even going on 8 years old.
Lolo... The thing is probabely a Pindel 16 - they have odd looking big (tall) hulls. Desirable? Rather not!
The Hobie 16 is a one design - they did not make a few boats with a different hull shape or volume.
Weight change was late in 84 and from there on...
Patrick
I've weighed a lot of boats. 83 and earlier weigh about 360 and up. 84,85 about the 320 minimum. I still have my 84 that stays at the lake for fleet races. 86,87 started creeping back up again to the 340 range. 88-92 got even heavier. We weighed some 89's that were hitting 385lbs. After the 93 nationals which a lot of east coast guys went to had thier 89-92 boats weighed and found out how heavy the were and proptly bought new boats in 94 that weighed in at or under weight. All the new boats are very close to minimum.
So can I assume the heavy boats are stronger - condition being the same?