Quality folding, travel, and commuting bikes

Reviving The Moulton Mountain Bike: A Portapedal Exclusive

I can’t even remember when I first became aware of the Moulton SpaceFrame bicycle. It was years before the internet, and the closest thing to Instagram was a youngster standing outside of your front door singing a birthday greeting. I must have caught a glimpse of it in one of the many bicycle publications that I used to pour over in my younger days.

That image, however fleeting, became buried in my sub-conscience until it unexpectedly rose to the surface when, in 2009, my architectural practice went to “hell-in-a-handbasket” during the “Great Recession” here in the U.S. It was that fateful economic event that spurred me on to start a business out of my life-long passion with bicycles and riding.

Furthermore, it was a passing comment from my pilot “sin-in-law” (he had not yet married my daughter), about the virtues and utility of a folding bike to carry along in his small Cessna. That gave birth to the idea of a bike shop dedicated to highly capable folding and separable bikes that can be easily stowed for travel, but still provide a quality riding experience.

Thus, PortaPedal Bike was born in the southwest Arizona desert, Phoenix metropolitan area. Because of its portability, quality ride and build, it became infinitely clear that the Moulton bicycle must become part of PortaPedal Bike’s offerings.

To my surprise, the North American Moulton distributor, Belmont Distribution, was not headquartered in New York City, San Francisco, Toronto, or even Montreal, but right here in my own backyard; the moon and stars were aligned!

The Moulton selection at Portapedal Bike

As we began selling these versatile traveling bikes, providing a smooth, comfortable, yet nimble ride, I came to learn some of the history of their design and development. I became increasingly intrigued with the AM-ATB developed by Alex Moulton, along with input from Angle Lake Cyclery in Seattle, Washington.

Here in Arizona, there are thousands of miles of trails circulating through some of the most rugged and beautiful scenery in the world. It was only natural that our state became a real hot spot for mountain biking. Indeed, it was mountain biking that got me back into the sport when I moved out west.

The AM-ATB was phased out in 1992 so all I had were the description and photographs in Tony Hadland’s excellent and thorough commentary on the SpaceFrame Moultons. Chapter 7 was dedicated to the history of the ATB and featured a memorable photo of Alex Moulton astride an AM-ATB somewhere in the forests of Washington state. He was dressed in casual attire and his pant legs were uncharacteristically rolled up. He looked like a kid having fun which is what mountain biking is all about.

August 1989 Mountain Biking For the Adventure magazine review

I longed for the ATB to be produced once more. The desire became even stronger when I unexpectedly was able to see one when I was visiting family in my home town of Buffalo, New York. It was on that trip that I decided to look up Doug Milliken who was instrumental in the research and design of the “Liner 2”, the fairing that was used at the 3rd International HPV Scientific Symposium in Vancouver, BC on August 29, 1986, when the Moulton AM-7, took, and still holds, the speed record for a rider in a normal riding position.

Doug, who lives just outside of Buffalo, had just come home from a long business trip, and was “working” that day watching a Formula 1 car race on T.V. He’s a consulting engineer for Elite Racing car teams. With all of that happening, he was gracious enough to have me over for a visit. He showed me a few of his Moultons and a device of his own design that measured power output of a rider, used prior to the Moulton trials. He then beckoned me to the garage to show me his daily ride: a Golden Yellow AM-ATB complete with racks and bags that he uses for his daily grocery runs.

My visit with Doug Milliken and his original ATB in Yellow

Well, that was the only inspiration that was required. As soon as I got back in the shop, we began putting together a spec list for our own trail-worthy Moulton. The primary question was if the TSR frame could accept the wide tires necessary to handle rough or loose dirt surfaces. A pair of Schwalbe “Little Joe” 20”x2” knobbies were installed on 36 hole Sun Ringle Rhyno-Lite XL welded rims, laced to Shimano XT hubs. The frame readily handled the tires with a bit of room to spare. V-brakes must be used to allow the use of these wider tires.

The original ATB was fitted with a 48-38-28 tooth triple crankset and a 12-22 tooth 6-speed cassette. That combination yielded 25” to 80” gear inches, which gave a rider a nice, low gear range to tackle hills.

We opted for a 52-36 tooth Shimano FC-RS500 double crankset and a 11-34 tooth Shimano XT 10-speed cassette. That gave us a quite wide range of 19-88 gear inches that should be able to handle most any roller coaster type trail a rider may encounter.

The bike was tested at some local trails exhibiting loose gravel on hardpack and small rock gardens; it performed admirably. You must be a bit more careful reading the trail ahead and avoid small, deep depressions that present no problem for 29” wheels, but may stop a 20” wheel dead in its tracks.

Test riding on loose on hard pack at Gateway to the McDowel Mountains in Scottsdale AZ

The Moulton suspension did its job isolating shocks and keeping both wheels tracking properly on the ground. The standard front spring in conjunction with the wide tires at low pressure absorbed the bumps without much bounce-back, allowing for a controlled ride on the rough stuff.

The tight center knob pattern of the “Little Joe” tires allows smooth, quiet riding on hard pavement, but it’s nice to know that when an irresistible dirt trail presents itself along the way, this mountain set-up will allow you to take it with confidence.

Another version we built in Burgundy

It’s been very satisfying representing Moulton here in the southwest and seeing how much pleasure this bike has given our customers. It gives them an agile, portable bike that still maintains a high degree of performance and is just plain fun to ride! One of our elderly customers remarked, after his first ride on his new Moulton, that the last time he rode 40 miles without wrist, shoulder, and neck pain, was 25 years ago. He said that when he got home after riding his Moulton for the first time, he felt like he could turn around and go out for another 40 miles!