Mule Packer-the D.I.Y. Bike that Really Packs!

The  Mule Packer bike is definitely the simplest method of building your own low-cost demountable travel bike using only common hand tools. It consists of a pair of demi-frames cut from two 1980’s mountain bikes, one larger than the other by 2-3″ that sleeve together with no added joints, hinges or other mechanisms. This is possible when the bigger frame on the front has larger diameter steel on the full-length down tube so that it will sleeve over the stub of the down tube on rear half with slightly narrower tubing. The second sleeve joint uses the seat post to connect the seat clamps of both halves.

However, there is a catch–both frames must have the same downtube angle at the bottom bracket and it takes some persistence and luck to find two frames of different sizes that nest together perfectly. So you need to have a a good source of older (junk) bikes that you can pick through before they are carted off to the scrap yard. 

Mule Packer Essential Features:

  1. Two basic steel mountain bike frames with moly tubing and cast fork ends.
  2. The front frame is 2″ to 3″ bigger and uses larger diameter tubing on the down tube than the rear half.
  3. 1.25″ diameter oversize plus tubing on the front sleeves nicely over a rear frame with 1.125 oversize.
  4. Tools:  a tape measure, bevel gauge, caliper, hack saw and a file.
  5. 100% “failsafe” fully tested design that is ridable even without the clamps tightened.
  6. Demounted, it measures 25″ x 26″ x 10″ < 62″ limit for airline luggage. 

The result is a rugged frame that rides and handles like a standard welded frame. The joints are rock-solid and suitable for unsupported fully-loaded travel on the world’s toughest routes. It is easily and quickly taken apart with hex wrenches for truck, bus or train rides. The prototype Mule Packer (photo above) flew from the USA to Chile in January, 2016 at no charge on United Airlines and made its first long-distance ride on the Carreterra Austral. We covered 500 kms of jarring dirt roads, and another 1000 kms on asphalt. I even broke it down for a few bus rides with no problems.

How Thinking “Inside the Box” Created a 26″ Wheel Travel-Bike                                  I was aware that a frame could be professionally hand-built, cut in half, and fitted with the well-known and expensive S & S couplings. But I challenged myself to find a simpler, cheaper and better way to achieve this without welding, brazing or machining. I began by experimenting on  several junkers, cutting them up into “half-frames” with a hack saw. (They were destined for the scrap heap anyway.)

 

Upper joint uses long seat post with two clamps to couple front and rear frame halves for 100% secure joint.

I made many test-rides on the trails around Astoria, and on the west hills of Portland, including some rough descents, and couldn’t feel any difference at all from a normal frame. 

To ensure the “packability,” you will need a modern two-piece style crank that doesn’t require a crank puller.

The lashing was added as insurance in case the clamp ever slipped in Chile, but was never needed.

I perfected the packing system using a cut-down cardboard bike box, then built a thin plywood box around it to protect the wheels from damage while being thrown around by the airline. I actually spent more time building the box from thin plywood than the frame! Then I  salvaged a telescoping handle and wheels from a worn-out rolling suitcase, strapped it to the box, and rolled it around the block. I weighed it and found it was well under 50 lbs/24 kilos.

Mule Packer ready to box up--handlebars shown outside package for clarity, they actually go in space between wheels. inside package.
Mule Packer ready to box up–handlebars shown outside package for clarity, they actually go in space between wheels. inside package.

Why is it called the “Mule Packer?” 

  • mule becausit is a cross between two different species (of bike)
  • packer because it packs small enough to ride on a plane–or a mule
  • The name “Mule Packer Bike” is copyright P. Marsh 2014.

How suitable is a 26″ wheel bike? I enjoy touring on good roads with 700c wheels, but 26″ is the maximum tire diameter that falls within the airlines 62″ rule (26″ x 26″ x 10″) and is also the most common and maybe the only size of wheel, tire and tube available outside the developed countries. It’s also stronger, more versatile and great for commuting; so I built up an old 26″ wheel frame with slick tires for my coast-to-coast ride 2016-18 carrying all my camping gear.
Is this a first in bike design? This page has been up since 2015 and has had a lot of views. No one has challenged my claim to be the first person to  demonstrate this sleeving principal on the web. If it’s been done before, I can definitely state that I had no knowledge of any previous version. 

The Mule Packer and me at a hostel in Valparaiso, Chile--city of murals.
The Mule Packer and me at a hostel in Valparaiso, Chile–city of murals.

If this appeals to you and you can find a matching pair of frames–well done! I am prepared to advise on the finer points of how it’s done and send you a few photos. In return, I request a small donation of $25 to support this web site and my continuing work on “re-cycling.”

This pairing is notable for having a modern design on the front half with sloping top tube and very large diameter steel tubing on the downtube. Luckily I found this fits precisely over  a standard rear triangle with oversize+ tubing without a shim. 

 

 

RECOMMENDATIONS FROM BIKE INDUSTRY PROFESSIONALS

A U.S. Olympian 1960 & 1964; member of the road cycling and mountain biking halls of fame, and designer of a very early mountain bike in 1976, said this about the Mule Packer: “That is truly the most creative bit of bicycle work I’ve ever seen.”- Victor Vincente of America,

Thomas Ahearne, one of Portland’s top frame builders, and a prize winner at the North American Handmade Bike Show, said “I would have said that was impossible….but you’ve done it” when he saw the Mule Packer.   

Footnote: A little over a century ago, the U.S. Patent Office estimated that about two-thirds of all new patents were bicycle-related. While the figure is no longer quite that high, bikes continue to inspire inventors in a way that few other devices do. You can see this on websites like Kickstarter where  today’s bike-riding inventors present a never-ending stream of bike gadgets they all claim will “enhance your cycling experience.” Well, the Mule Packer isn’t about one of those wacky gizmos, and it needs no batteries or smart phone to make it work!

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One Response to Mule Packer-the D.I.Y. Bike that Really Packs!

  1. Jeremy Kurtti says:

    I had the pleasure of viewing Peter’s handiwork at Bikes & Beyond. Nice job. Very nice indeed.

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