Fibreglass Hobie?

[Yuz]

ELM, I agree, "knocking off" a design isn't a good thing, but I'm not doing this for profit, just a one-off home project. The finished (if works out ) unit will have to be different anyway, since there's no way to achieve an exact copy with GRP... If anything, Hobie will make some profit on a mirage drive, fittings, accessories, etc.
World domination one step closer

[Tormentor]

and a couple more resources for you, there's some nice designs on the Jemwatercraft site, easier to build and lighter than 100% fibreglass and a couple of builders have included peddles in their builds

http://www.washingtonwoodcraft.com/

http://www.jemwatercraft.com

no affiliation other than a satisfied customer

[maccayak]

Design your own with all the things you think should be in a yak, or design your own drive system that will fit into a hobie, but a better version (one that does not bend when you hit a tree stump etc). Now that would be good.

Geoff

[breambob]

I think hobie would only take issue if
a. they found out about it
b. you started selling the them to the extent that your kayak impacted on sales of the real thing

I reckon as long as its done respectfully you wont have an issue.