Birdy (bicycle)

The Birdy is a folding bicycle designed by Riese und Müller. As of 2007 over 70,000 have been sold.

Released in 1995, it was the first fully suspended folding bike. The ride is regarded as more sporty than the Brompton, thanks in part to a stiff single-piece aluminium frame with road bike rider geometry and no hinge. Some prefer its stiff suspended ride and rapid acceleration to that of a full sized bike.

Specifications

The Birdy uses standard rear dropout spacing, which allows a wide range of gearing options. Standard options include: 8-speed hub gear, 8-speed derailleur, 24-speed Shimano Intego, Rohloff Speedhub 14-speed hub gear. Available accessories are mudguards, mountain bike tyres, front and rear folding racks, bags and lighting sets.

Uses

With its wide range of gearing options, stiff frame and basic suspension, the Birdy is suitable not only for commuting but also for touring.

The combination of smooth but stiff ride, fold, and quirky looks have created a fetish for the Birdy in Japan. It also has a large following in the UK, Europe, the US, and Australia. The Birdy's folded size is similar to the 20" Dahon folders: larger than a Brompton, but significantly smaller than a Bike Friday (including the Tikit).

This is one of the most versatile bikes on the market, offering high performance for fast group rides, comfort for century rides, and sturdiness and luggage capacity for loaded long-distance touring.

Advantages

The primary advantage of this bike over other performance folders is that it folds quickly into a small package. Thus, it can be taken into stores, onto trains, and into the office, yet can also be used for cross-country touring or fast group rides. It is much easier to fit in a suitcase than comparable Bike Friday or Airnimal models, but less easy to pack than a Brompton. There is no other hinge-free performance bicycle that is small enough to serve as a multi-mode commuter or that fits into an airline legal suitcase with minimal disassembly.

One other major advantage is the suspension, allowing for a smooth ride on small wheels. The suspension is anti-dive and has minimal impact on pedalling efficiency due to its stiffness, while improving rolling resistance on rough surfaces. The suspension can be adjusted using different elastomers (small pieces of rubber that serve as suspension).

Like most other quality folding bikes, it has no frame hinge that can fail. Unlike those bikes, both the front and the back points of contact serve as latches and shock absorbers. Thus, the downward force of the rider holds the bike together in such as way that the latches cannot fail while providing shock absorption. Dahon makes a number of performance folders with frame hinges.

Disadvantages

Birdy is fussy to fold. It can take weeks of daily folding to get the fold under 10 seconds. Even experts occasionally experience snags when folding the bike. However, experienced users can fold it faster than the Brompton.

It is expensive, costing as much as custom made bikes. Component selection can sometimes seem illogical, with lower level Capreo components on the top-of-the-line monocoque frame, and higher quality SRAM X7 components on the less expensive model. However, the Capreo groupset is specifically designed for small-wheel bicycles. Tire selection is adequate, and Kevlar-beaded tires, which can be folded for carriage in panniers, are available (as of late 2007) as the Schwalbe Marathon Racer.

Birdy uses less common 18" diameter wheels instead of the more common 20" wheels found on BMX bikes. This allows for a more compact folded size but makes finding replacement wheels, tubes and tires more difficult. It is easy to fit more common 17" and 16" wheels if 18" wheels are unavailable. Some have even fit 20" wheels to the bike.

The unique front folding mechanism is long, weak, and more flexible than others; the tolerance of linkages amplifies the flex, causing the trailing arms to wander; thus an old Birdy may be unstable at speed. The direction of Birdy's trailing arms are opposite to the way of traveling, unlike similar design including the 1946 Vespa.

The Birdy is limited by the longer seatpost and stem common to most folders. These components not only add weight to the bike, but the longer stem limits the exent to which the rider can pull on the handlebars. Thousands of miles of this activity can damage the headset or weaken the stem mount. The larger head tube on the Moulton gives it better hill climbing and sprinting abilities. However, with proper cycling shoes, Birdy riders can be found in non-UCI racing events and in pacelines of fast group rides.

Outside of Japan, the frame is only available in aluminium; in Japan, titanium models also exist.

Average price

The Birdy monocoque frameset costs approximately $1,000 US without parts, so even low-end models are pricey. Equipment set up differs greatly from country to country. In the US, entry-level bikes (non-monocoque) cost approximately $1,000 and are equipped with low-mid range Shimano Alivio components.

In the UK, entry-level bikes equipped with Deore/Alivio components can cost approximately £800. High-end titanium models (rare outside of Japan and Australia) can cost over US$3,000. Japan is the biggest market for these bikes and offers a wide array of cost-effective choices. In Japan, the bike is distributed as the Bianchi Fretta (OEM) and BD-1.

Weight

Some riders have reduced the Birdy's weight to 8 kg using racing components. However, stock bikes range from under 10 kg (for the new Birdy Speed with Tune and Shimano Ultegra road components) to 11.7 kg, depending on the setup. The heavier bikes tend to have 3x7 gearing systems, involving an internally geared rear hub and an external derailleur.

Transit capability

A Birdy can fit into a standard airline-legal 29" suitcase, but this requires the pedals, wheels, and rear rack to be removed. Some Birdy owners have had difficulty fitting both the bike and the rear rack into a standard suitcase. When fit with thin racing tires and short pedals, the bike can fit in a suitcase with less disassembly. With a larger case, no disassembly is required. A standard slipcase must be used on some trains and buses.

The Birdy's dimensions are: Width: 35-39cm Height: 58-61cm Length: 76cm to 79cm

This is small enough to take into businesses, on buses, and to easily pack for travelling. However, it is too large to fit in a locker or most overhead bins. It is the second smallest of the quality folding bikes (behind the Brompton), and is the smallest performance folder as of mid-2007.

Options

The Birdy can carry 10 kg of luggage on the front rack and 25 kg on the rear rack (both racks are optional).

An optional rolling rack allows the Birdy to roll when folded.

Models are offered outside the US with hub dynamo systems. Fenders are available everywhere the bike is distributed.

Distribution

The Birdy is distributed in Europe by Riese und Müller, in Australia by BikeBox, in Japan by Mizutani Bikes, and in Singapore by www.foldingbikestory.com, Diginexx.^[1] Some distributors make custom modifications to the bicycle.^[2]

References

^ Birdy distributors
^ e.g. Japanese AddOns

External links

[1] Birdy distributors

[2] .g. Japanese AddOns

[1]

[2]