I always use bow and stern straps to transport a kayak. In the past I’ve been using two straps across the kayak, one in front of the cockpit and one behind it.
Is it also acceptable to use just one long cross strap, but loop it around both bars so that it crosses over the kayak both in front of and behind the cockpit? (plus the bow and stern straps)
The way I’m doing it now (with two straps), each strap passes twice over the kayak at each end, whereas with a single long strap it would pass just once over the kayak at each end. I can see that this wouldn’t be as strong, but I’m wondering if it’s sufficient.
I wouldn’t when they are on saddles
I use a strap in front double looped which gives basically two straps over the yak, and then a second one double looped over the back.
In seventeen years of carrying kayaks, I have never had one loosen up.
Jack L
What’s the relationship
between saddles and number of straps?
Personally, I always use two.
That way, if one should shift or fail for any reason you always have a backup.
Snug first strap, wiggle boat, snug the other, wiggle boat, check first strap, check second strap. Time and straps are cheap - boats are not.
Jim
Know someone who tried that
It’s not uncommon for WW folks to use just one strap for the boat, and often no bow line. It’s an understandable impulse given the shrimp size of the boats. But we know someone who arrived home with no boat after a paddle, and one hears of others.
Do it all the time
– Last Updated: Jun-06-11 11:45 AM EST –
If I want to grab a quick after work paddle on the local water way, I secure the boat as you descibe. But this is for a short slow trip,
Come to think of it,
yesterday I saw a northbound car on I-77 carrying a WW playboat that had turned about 45 degrees to the centerline of the vehicle. Makes you wonder…
Jim
I do this for very short trips
at low speed and can vouch that it works just fine. I’m wondering about longer trips at higher speeds (max. 60 mph).
Bow and stern straps serve as backup
Question: If you were driving at 60 mph and the center strap failed, would the bow and stern straps hold the kayak?
If so, you would just stop and add a new strap, right?
I’ve never had a strap come even close to failing in the last 30 years or so.
Did that person use bow & stern straps?
I ALWAYS use them.
Strap failure
It happens. I had a strap separate as I was tightening it over the hull of my canoe. It wasn’t old, abused or apparently worn. It was a name brand.
Short and slow only
other wise, like 6o mph, 2 straps, bow&stern lines.
Straps…
ALWAYS use two straps on the boat itself, I would never use less.
I use a bow AND stern line for the tandem, since its only on foam blocks. I use only a bow line for the 13’ solo, because its in Thule J-cradles that in all honestly are not likely to fail, short of the metal snapping, but I also stick close to home. Farther than 10 miles, I generally just slap a stern line on too, cheap insurance. Of course, I have Yakima Rail Grab towers on my Subaru factory side rails, and its far more secure than the Q-tower set up I had on the old Neon, and that traveled plenty of miles with the 72lb tandem beast on top 
Guess I will go with the majority here
Most links say “One strap might work, but two is better.”
Always looking for ways to simlify the logistics of getting on the water. But the term “cheap insurance” is meaningful, so I’ll continue using two straps.
The only time I use one strap
Is when the kayak is in the bed of the truck, and the strap goes around the kayak and the bed extender 
no but
Would not have helped much. Very short boat so it would have been noticed, but still a mess wit nh damage to car and boat
Huh ?
If they are on J cradles you don’t double loop them- No brainer !!!
Always, always
… use two straps across the body. It’s not because of strap failure (which could happen) but because of emergency braking or acceleration (which is much more likely). The front strap across the narrower width prevents the kayak from moving forward. The rear strap across the back keeps it from sliding backwards. You need both.
Bow and stern lines are almost always advisable, the exception being short, low speed runs (well below highway speeds). These are not there to prevent the kayak from moving backwards or forwards, but to prevent hobby-horsing at speed or over bad roads. This is particularly important if your kayak is long and the space between the rack bars is short. The effect is accentuated at speed – the up and down movement of the bow or stern can eventually loosen the straps, creating a very unsafe situation, plus it’s hard on the kayak.