While it is commonplace for modern bicycles, especially mountain bikes, to employ both a front and rear suspension this practice was only tried sporadically since the inception of the safety bicycle in 1885. For balloon tire bicycles there were only two makers who produced a true full suspension bicycle; Monark and Huffman.
In 1938 Huffman introduced the “Twin Flex” model. This bike had small springs located at the front and rear drop outs to act as shock absorbers. Unfortunately this proved to be a poor design and was immediately recalled. There is only on surviving example of this bike and it is referred to as the “death bike”. There are many stories how the name “death bike” came to be. Some claim the design itself was dangerous leading to the name. The likely reason though is the fact that the poor design almost led Huffman to ruin.
Miraculously Huffman was able to re-design the suspension within a few months and produce the second design Twin Flex which actually works pretty well.
I’ve heard many people complain about how the Twin Flex rides. Some of these people never even rode a Twin Flex. These bikes are now over 80 years old and there are a few factors that can lead to a poor ride to include worn bushings and weak springs. A reproduction heavy duty spring has been made and worn parts can be replaced although it may take some hunting. Once these parts are checked and the suspension is adjusted properly the Twin Flex is a great riding bike. I own four Twin Flex’ and the only problem I’ve ever encountered is the rear suspension binding and hopping on emergency (hard) braking.
Late in 1938 Monark introduced a twin suspension bicycle sold through Gambles department stores known as the Airman Comet. So far only two examples of this bike are known. One is a semi-complete bike that was house painted red. The other is a complete, original bike. There have been about four or five tribute bikes built as well.
The design used for the suspension on the Monark bikes is somewhat delicate. The spring fork used for the 1939 Monarks is called a ‘pencil springer’ by collectors. I have had about six of these forks and on every one of them the ‘pencil’ part was bent and had to be straightened. The springs for these are fairly small and can’t absorb a lot of load. A rider weighing more than 175lbs is going to bottom these springs out.
Some will argue there is a third maker-Colson. The reason I don’t include the Colson Twin Cushioner model from 1941 is that I don’t consider this a true suspension. Colson used rubber bushings to absorb shock and the design actually does very little in the way of acting as a true suspension.
For those that want something different either to ride or collect I would recommend the Huffman built twin Flex. While not cheap a well sorted bike is fun to ride and you’ll definitely stand out from the crowd. Enjoy the ride!