Bike Trailer Jackknife

A trailer jackknife can happen when you brake the tractor, and the trailer’s momentum pushes the back of your tractor around. With a bike trailer, the bike is the tractor.

On a seatpost hitch trailer like the Burley Travoy, jackknifing should be very difficult because the trailer is hitched forward of the rear wheel. I did manage this trick, however, by braking in a turn on a sand covered trail. I recovered quickly and didn’t fall, but it’s something to be aware of.

I loaded the Burley Travoy up with 30 pounds and tried to force a jackknife. I barely managed to lift my rear wheel only when I braked hard from over 20 mph. In retrospect, I probably should have tried turning more sharply in the turns, but since I didn’t actually succeed in jackknifing the trailer on camera I think it’s safe to say the Burley Travoy trailer is stable enough for general, non-racing cycling.

The jackknifing tests begin about 20 seconds into the following video.



10 Comments

  1. Certainly doesn't look like any jack knife to me. Your description or what you are alluding is a very big stretch. Any bike you ride hard into a corner and brake quickly is going to skid. Test is a complete waste and doesn't support your claim. Furthermore – where's a race where you would hook up a trailer to participate.

  2. Howdy, Fritz–

    I have a tendency to over-think bicycle issues, so I was kind of stunned when I saw this post. I have to admit, even as a long-term trailer enthusiast, I hadn't thought much about this issue. I suppose I considered it, years ago, but I dismissed it. I don't usually have more than 100 pounds of load and trailer (trail-a-bike, BOB, or Chariot), and I didn't figure it could push me around much. Sure, I feel them back there, but they're not that pushy.

    So I googled it, since everything bad that happens ends up in a blog or on Youtube. This doesn't seem to be a big issue. Most posts (the ones that don't link back to you) involve trying to back a trailer up, which can be tricky, but isn't a big danger.

    I also see the point about mounting the hitch closer to the center of the bike, but I think mouning it up on the post negates the effect. Sure, my BOB trailer, hitched to the rear axle, does have more leverage over the rear end. But it also has weight on the rear wheel. The Travoy, on the other hand, has leverage up high, where it can lift the rear wheel as you brake. It seems more likely to lighten up the rear end.

    Okay, now I've given it more thought, and maybe I'll be a little more aware on loose surfaces when I'm carrying more than average, but mostly I'm back to dismissing it.
    Happy Trails,
    Ron Georg
    Corvallis, OR

  3. Howdy, Fritz–

    And it's not even April Fool's. No wonder I find your site so entertaining.

    In my little search, I did find one British site (I'm assuming so, anyway–he called a camper a caravan) which took the issue quite seriously. People will worry.

    By the way, did you hear they removed the word “gullible” from the dictionary?

    Happy Trails,
    Ron

  4. Today, bringing home some groceries in my travoy in the included travel bag, I did find items in the bag kept shifting when going over curbs. They kept pushing the bag onto a wheel. Not a good thing.

    Next time I won't let the bag boy pack the bag.

  5. Today, bringing home some groceries in my travoy in the included travel bag, I did find items in the bag kept shifting when going over curbs. They kept pushing the bag onto a wheel. Not a good thing.

    Next time I won't let the bag boy pack the bag.

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