Check out this thread.

www.seabreeze.com.au/forums/Stand-Up-Paddle/SUP/Board-Carrier-something-with-wheels/

I recently bought The Mule Transport System on ebay from aussie.

Actually haven't used it yet but i like the handle and strap along base of the board making it a little more secure on rough terrain, and heck i didnt trust myself just hanging onto the front of the board.

Good luck with it

Go to Bunnings and grab one of these for $20. Get out the angle grinder and take the front bit off. lay some old carpet / foam over the frame and tie the board on with 1 or 2 elastic ties. Probably will not look as flash but you will be all done for under $25 and 15 mins work. We made a few of these up a few years back to move some kayaks around - they worked a treat.

I have a SUP sling. I used it a few times.

It's a bit of a pain to fit on the sand. You get wet sand jammed between the straps and the board. The sand can scratch the board.

It's ok when it's dry but when it's wet it slips around the board, especially if you heft it by the paddle in the holder. The grip comes from friction and tightness of a couple of buckles.

The shoulder strap is huge and you need to wear the bum bag that comes with it for storage. It's comfortable enough to wear but there's no extra room for other stuff in the bag.

The best system is to have a board light enough to carry. My board weights 5.6kg and it's so easy to stroll down to the beach.

Having two leash plugs either side of the middle of the board are good. You can slip the paddle through some loops and use it as a handle. If your board is heavy you could use a shoulder strap connected to the leash loops. Nothing to slip. No fiddley buckles to try and get tight.

Naish used to do a strap with just a couple of loops at each end. Simply slip the loops over each end of the board and the weight of the board pulls the loops tight. That's a nice simple system and the strap can fit in the pocket of your boardies.

Thanks for the responses! So maybe the Mule Transport System is the best option, but can i also carry two boards on that thing? And how can i take my other stuff like my wet-suit? And yes, it is expensive.. But i think it's still the best solution to transport my Supboard with a bicycle.

And is there maybe something that also can transport my Windsurf equipment? And what about a Kayak?