I need to know a different way to secure the bikes in my trailers without using tie-downs.

 

you will still need to tie it down

 

Yes, even with a chock, tie it down on a trailer.

 

www.bikersgostrapless.com

 

A large electro-magnet?

 

S&S Cycle makes a similar product as the bikergostrapless costs approx $375

 

The bracket kits have already been mentioned.
Have you considered chains instead of straps. What about expanding foam?

 

get your ol to ride back there sitting on the bike holding it up..

 

Wheeldock

The owner claims that the straps came loose when they were developing the product and the bike stayed put.

Honestly? From personal experience with this product, put the wheel in the wheeldock and use the one strap to ensure the wheel doesnt roll backwards. Put the bike in 1st and roll out!

We love ours

 

I use one of these and they're excellent in my opinion. If I had it to do over again, I would have seen how much the Roberts would have charged me for some extra under plates. I use three different trailers so I made two extra sets of under plates and just move the top fixture to whatever trailer I'll be using.

Great product and great people to deal with. Money well spent...

Edit: I've never used straps with the Roberts fixture.