CliffordK

I've always been reluctant to purchase Quick Release Trailer Hitches. They just don't seem to be as strong as frame attachments.

But, a lot are in use.

What are people's thoughts about them? Ever broken or bent a QR spindle?

I mostly keep my light-duty loads under 100 lbs or so, but may get up to 200 lbs on occasion. Anything over 200 lbs usually means the cargo bike & trailer.

Anyway, using a QR attachment would give me a lot more flexibility for bike choices. Also, I think my Burley trailer has been damaging the paint a bit

MillingHead_Sun.jpg

coldbike

I've hauled 250 or so pounds many times in my old Chariot trailer with a QR attachment. I've never broken a QR hauling or using my OMM racks. The only QR I have broken was when I was putting it on the bike and it broke while tightening the clamp with the extra leverage of a screwdriver.

fietsbob

if you get the QR tight it is in tension, the way it was designed to function the shear firces are not carried by the QR shaft, but the ends,
and low cost, internal cam QR are steel on the ends..

of course the way you load the trailer, you can put a smaller amount pressing down on the tongue, most on the trailer wheels..

I note, Burly has dropped their forged aluminum hitch in favor of a steel one.. (seen bent forged Aluminum one in LBS , trailer left on consignment)





....

KD5NRH

Single sided attachment like that, I can't speak for, but while I've heard of tons of failures of BoBs and clones, the QR hitch hasn't been a common point of failure. Off the top of my head, I can't recall ever hearing of a failure there; it's usually a weld elsewhere on the trailer that lets go first.

FBinNY 

The load on the QR is limited by the forward force you can generate. That's pretty damn low (no matter how strong you think you are), so no worries about pulling a trailer by the skewer, regardless of how heavy that trailer may be.

The more serious concern with a heavily loaded trailer is stopping it without losing control of the bike. Balance the trailer in a way to have positive tongue weight. The more the better (within reason) and you should be OK.

CliffordK

Yeah, I'm not sure if the more the better is the rule for tongue weight (for the second half of the load above).

MillingTable.jpg

As far as stopping, on the level, speed is limited by the power I can apply to get the thing moving. So with a heavy load, I may be limited to significantly < 5 MPH. So, perhaps no more stopping force than I would have if I was riding 20 MPH empty.

Hills are a different story, but I hit very few urban hills where I can't plan ahead.

Anyway, there are also several different types of trailer hitch attachments. The cheap kiddie trailers use a spring attachment that has problems with either significant positive or negative tongue weight.

My Burley trailer has a more positive attachment, and can deal with weight a bit better.

You may be right that if one designs a hitch right, the forces on the QR could be minimized. Perhaps design the hitch to pull more or less straight back, rather than to the side, but also limit the ability for sideways forces on it.

One could, of course, do a sandwich attachment around the dropout, slightly expanding the OLD spacing. +1mm on the inside? Channel iron around the nut?

FBinNY 

That's covered by the "within reason" I included. Also, I was talking about a trailer attached at the axle, which makes what you showed impossible.

The issue is that hard braking unweights the rear wheel, and there's the danger of the trailer pushing it sideways, the same way that truck trailers jackknife.

Note, that braking also shifts the trailers balance increasing tongue weight, so it's a question of getting everything to work in harmony. But always remember that as hard is it is to pull a trailer, stopping one in an emergency is harder.

bicyclridr4life

My trailer (a 2 kiddie converted to cargo) has a chainstay mount hitch.
My bike has quick release wheels, front and rear.
On average, I put 4,000 to 5,000 miles a year on the bike and trailer. (the trailer is just so daRn handy, I never go anywhere without it.)
I've never had a problem with the skewers.
After 8 or 9 years of use, I did have to replace the heater hose they used inside the spring on the hitch last year.

On my bike specific trailer (also an old kiddie trailer) the chainstay mount would not fit the bike*. That trailer uses polyurethane, instead of a hose inside a spring on the hitch.
I removed the polyurethane from the chainstay, elongated one of the holes, and bolted it to the dropout.

*Cheap Full suspension mountain bike. It does not have clearance for that particular chain stay hitch in the rear triangle.

CliffordK

Oh, one size never fits all!!!

Heater hose in the spring?

My Avenir and Bell trailers just clamp onto the chainstays, but use simple springs. I've actually had problems clamping the trailers to my road bike. Too thin of chainstays.

The Burley uses some kind of a flex link. I'm not quite sure, but it pulls much better. Clamps onto both the chainstay and seatstays. It fits well onto several bikes, but perhaps would have issues with an IGH or disc brakes.

However, my question was about a third type of hitch that simply is either bolted to the hub axle, or connected via quick release. Then decouples from the trailer with a pin.

Similar to this, or some variation of this.

pickettt

Friction between the frame and bracket is bearing the force, not so much the QR shaft. Granted, the quick release lever is creating that friction.

fietsbob

& Skewer is stretched, in tension . like a spoke is in tension..

Axle is in compression, that's why bearings of well adjusted hub is a little loose when the QR wheel is removed..