Full-Moto Frame
The Full-Moto has been designed for having a blast in the woods - for relatively short, fast outings, providing the rider with the confidence to attack a trail and get loose, to be engaging and involving. To achieve this, I wanted a bike whose limits are easy to approach and fun to reach, something that I feel current mountain bike designs have failed to properly address.
Two separate things have conspired to make me question the modern mountain bike: my slightly odd physical proportions and a nagging sense that bike geometry took a wrong turn sometime in the late 80s. Firstly, I have very long legs for my height. Despite being a not-too-unusual 184cm tall (about 6 foot), I have a lofty saddle height of a little over 82cm (about 32 inches). One of the ramifications of this is that I have always struggled to achieve a suitable handlebar height and so have probably given more thought to the placement of my hands when riding than most people.
Secondly, most mountain bikes still place the rider in a body position that can trace its roots back to the world of road bikes from the 1980s. For example, a 2017 Specialized Tarmac road bike (about as racy as road bikes come) has a stack to the handlebars of around 630mm and an equivalent reach of about 490mm (58cm frame size). Meanwhile, a 2017 Specialized Enduro 650b, raced at the highest level in the World Enduro Series, has a stack to the handlebars of around 660mm in a size large, just 30mm higher than the Tarmac. And with an equivalent reach of about 460mm, that’s also just 30mm off a World Tour road bike.
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Stack and reach measurements to the handlebars for two very different bikes
The difference between these two bikes would almost fit on a postage stamp. And if you compare a sportive road bike with a trail bike these numbers get even closer. How can two bikes supposedly optimised for two very different purposes be so similar? To be clear, this isn’t a situation unique to Specialized, quite the opposite. I have simply chosen Specialized because they are such a well-known company that are representative of what is currently happening in the world of mountain bikes.
If anything, current trends in mountain biking are making the situation worse rather than better. The ongoing shift towards ever longer wheelbases has been achieved, at least in part, by steeper seat tube angles and a longer reach to the 'bars. This tips the rider forwards, requiring their hands to support an ever-increasing proportion of their body weight. This issue highlights something that is often overlooked or confused in mountain bike design - the difference between a stable bike and a stable rider. While mountain bikes may have been getting ever more stable, their riders are being forced to adopt ever more unstable body positions.
If anything, current trends in mountain biking are making the situation worse rather than better. The ongoing shift towards ever longer wheelbases has been achieved, at least in part, by steeper seat tube angles and a longer reach to the 'bars. This tips the rider forwards, requiring their hands to support an ever-increasing proportion of their body weight. This issue highlights something that is often overlooked or confused in mountain bike design - the difference between a stable bike and a stable rider. While mountain bikes may have been getting ever more stable, their riders are being forced to adopt ever more unstable body positions.
A comparison of modern bike geometry (black - my XL Last Fast Forward) against my new bike (grey)
Furthermore, this issue seems to get worse the taller you are as most bike manufactures fail to increase their frames’ stack heights in proportion to either their reach or likely saddle height. Trek, for example, maintain exactly the same stack height across their first four frame sizes on their 2017 Fuel EX, supposedly covering everyone from 5’1’’ (155cm) to 6’4’’ (193cm).
Stack:Reach ratios across a range of frame sizes for some popular 2017 mountain bikes
For a bike to handle well it must do two fundamental things. Firstly, it must place the rider in a stable position, enabling them to maintain balance while descending. This has the best chance of happening when a rider is supporting all of their weight through their legs in what is known as an Athletic Stance. Secondly, a bike must give the rider the best chance of controlling it by ensuring that a rider’s hands are uncorrupted by the donkey work of having to support any significant proportion of their body weight. Both are inter-related and both sound pretty obvious, but I believe that these two attributes are compromised on most modern mountain bikes, which continue to mimic road bikes far too closely.
Interestingly, the body position that I am trying to achieve is very similar to that of a Motocross rider. This position is more upright with the riders weight centred over the their feet. If anything, the closest that mountain bikes have ever got to placing a rider in a similar, stable position were the original Klunkers, repurposed from Schwinn beach cruisers in the 1970s.
Interestingly, the body position that I am trying to achieve is very similar to that of a Motocross rider. This position is more upright with the riders weight centred over the their feet. If anything, the closest that mountain bikes have ever got to placing a rider in a similar, stable position were the original Klunkers, repurposed from Schwinn beach cruisers in the 1970s.
A rider in one of the world’s largest motorcycle races, the Enduropale du Touquet in France
(www.motorcyclecommunity.co.uk/beach-racing-le-touquet/)
(www.motorcyclecommunity.co.uk/beach-racing-le-touquet/)
It is this thinking, described above and through my blog posts, that has been the starting point for the Full-Moto frame.
