Hi,

I agree with the others, tying them down to the racks is the main thing (and ensuring the racks are secure to the car!). I've carried 17' long boats 2000km's at 120km/h just tied to the racks.

However, the other option I've seen for short cars/long kayaks is (where the car has a boot) is to make an attachment for the tow bar. Like this: flat plate with hole, which slips over tow ball thread (or other bolt) with post welded/bolted (L-bracket) to it. Like a bike rack on a towbar.

Then attach a cradle to the top of the post. Kayak sits in cradle, which means you can then have weight further back and less overhang at the front. Attach straps and flag to rudder, easy! You could also add a roller to this support to make getting the kayak on & off easier.

Regards,
Darren
Melbourne, Australia