Cycling Related Video's


Thursday, March 4, 2010

Getting hitched

I wanted to have a look at the varoius ways in which a trailer can be connected to a bike or trike. methods at the bike end of things include couplings to the left chain stay (or both), the rear axle bolt (or both), the seat stay or the rear luggage rack. Here's what I've found. As ever, novel solutions from your own projects are always welcome by comment or email.. Also is a great source of pictures and videos to give you help and inspiration for your home-built.

Chain Stay.

Bikes at work of Iowa, USA produce heavy duty ladder frame trailers designed to handle 500lbs (226 Kg). A complete trailer or trailer kit might be a tad expensive to ship but they will sell you parts like their tough tubular tow arm which attaches to the chain stay, ahead of the axle as pictured below. To allow movement up and down & left and right, Moz from New Zealand  made his hitch (above) to include a plumbers spring. I had to enlarge the picture so that you could see the spring on top of the tow arm (the trailer is standing on it's rear end).

Axle Bolt.

These often involve a secondary bracket to the chain stay to prevent the fixed part of the hitch from twisting outward to the left. This one found on a you tube video features a universal joint (seemingly from a small front drive car) on the trailer end which anchored by  a split pin to a U shaped bracket which attaches to both axles. This solution is also used on the BOB Yak, the Mission monowheel trailer and many homebuilts such as this green one from Joe Dillon who uses it in his cycled parcel delivery business Cycle Link.

Seat Stay.
This is a common way of adding trailers and is used commercially by Roland, Cam Carts, Mission and many others. You need a clamp or collar to go around the saddle stem and a small universal joint connected,  either attached to the collar or the trailer's tow-arm.. The UJ could be a stip of truck tyre drilled through for attachment, a short length of plumbers pipe-bending spring bolted into tubes at each end or, as pictured a properly engineered joint. 

Luggage Rack.

I'm not quite sure about the strength of the these as rear luggage racks are designed to take weight in a downward direction and not rearwards. The  agricultural tractor hitch would work here. A ring on the trailer end inserts between two plates and a pin drops down through the top plate, the ring and then the bottom plate. the pin could then be drilled through to take a padlock. Alternatively you could bolt or weld an upright pin to the rear rack and have a ring on the trailer end.
This blue trailer found at Zedomax is made of wood. It clips onto a custom wooden box on the back rack. Seems a bit lightweight to me though. An advance on this idea is to use horticultural grade hosepipe between the bike and trailer as a universal joint then put a brass quick release hose coupling in the middle. Simples!
This idea is illustrated here complete with .PDF plans to download.

And finally, Paul Elkins built a camping trailer  from bits of scrap to go camping in style. I don't know much about it but you can find it here.

Let me know about your homebuilts soon.

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