I always block the frame right under the engine with a stack of 2 x 12 by 1 foot long before tightening the straps down so there is no suspension working to loosen the straps. It also prevents the bike from falling over immediately if a strap chafes or whatever. It keeps the bike from moving around at all.
Gettingold Dave uses this method. I prefer to have the bike ride on it's own suspension.
My trailer rides smooth, but the bottom line, 15" tires only cover so much ground, and there are roads out there that can make for a jarring ride. Remember, most of our small trailers have limited suspension (of which the torsion is way smoother) and they don't have shocks.
I think that if the bike is being tied down so tight as to cause issues with the straps, then it is too tight.
The straps we use will all stretch a bit after being torqued down (about 10-20% is possible with nylon). Best way to counter that is to ride a bit and then adjust the straps.
We use straps instead of chains or binders because they do give a bit.
- My preferred method is:
- Tie the wheel down securely to the chock
- Straps somewhere up high on the front to minimize side to side motion-lean
- Straps to the saddlebag guards to stop the rear from slipping side to side
- And if on a long tow - one strap around the rear wheel to keep a rearward pull for those "unexpected" stops
Now, when I have 2 bikes in the trailer, especially dressers, I tend to use extra straps. My trailer is 6.6' on the inside and that is the minimum for 2 dressers, staggered.