When making the decision to change the setup of our gravel bike to fit it out with a flat handlebar, what exactly can we expect to achieve? There is the potential to transform it into a completely different beast, expanding its off road potential. Maybe we can tap into a riding spirit of a bygone time, or even modify the setup to create a bike that is dialed in for ultimate performance during endurance events.
Here will explore the ins and outs of making this conversion to our gravel bike, and analyse some of the factors we need to take into account before opening the tool box.
The process is not as simple as just bolting a new handlebar onto a gravel frame. When we look at the geometry of a conventional gravel bike, or any drop handlebar bike for that matter, we have to take into account the bike’s reach when combining the shape of a handlebar with the correct stem length. Drop handlebars have a built-in reach of anything from 65mm to 100mm. When we consider this, plus the added extension that comes with using STI style levers, it becomes clear that we may need to use a longer stem in order achieve a similar rider-compartment measurement. We will also need to think about the width of the handlebar we choose to use – a wider bar may warrant the use of a shorter stem as this will mean that the rider’s arms are extended further away from the body.
Length of the stem may also influence ride characteristics. A shorter stem gives a more responsive steering feel, this why we often see stem lengths of less than 60mm on mountain bikes. A longer stem promotes more sedate steering characteristics, increasing stability at speed. This is one of the reasons why longer stems are commonly fitted to road bikes. However, we will need to consider these effects on handling when we fit a flat bar. If we are looking to achieve handling closer to that of a mountain bike, we may need to fit to a shorter stem which will most likely have a negative effect on the fit of the bike, making the reach overly short. However, another way that we can alter a bike’s reach or rider compartment measurement is to fit a seatpost with more setback. Moving the overall rider compartment position back will mean that we can pull in the required stem length slightly and therefore work to create a more responsive steering feel. But in making such changes, we must also consider how they will affect the position of the knee over the bottom bracket axle, and the possible change in crank length required to maintain optimal pedaling efficiency.
Of course there are advantages to choosing to use a drop-handlebar over a flat-bar; the shape of a drop-bar allows for a greater range of hand positions when compared to a flat-bar, aiding comfort. We can also achieve better aerodynamic body positioning when using a drop-bar. But this doesn’t stop the rider from getting creative with accessory mounting when using a flat handlebar – quite often we see flat-bar users mounting in-board barends to emulate a position similar to that achieved when riding ‘on the hoods’ of a drop-bar/road bike style handlebar setup. We also regularly see cross-country mountain bike racers employing a tucked, aerodynamic body position when it is required, so if the rider is sufficiently flexible, it is still possible to strike a speedy pose as and when required.
If the rider’s focus is more off-road orientated, the choice of a flat-bar over a drop-bar is often a safer option and may allow for better control during rough descents and on rough terrain in general. Another scenario to consider is the flat-bar’s practicality in an urban setting. Although urban riding may seem miles away from the off-road riding that encourages the use of a flat handlebar, when using one in motor traffic we can use the more upright position to our advantage and keep a clear view of the road around us. Some may look at the gravel bike in this configuration and see very little difference from a hybrid bike. Perhaps they are right in some aspects. Whereas hybrid bike development seems to have taken a direction where performance is less in focus, gravel frames are generally more aggressive in geometry, and even when fitted out with a flat-bar they will behave in a sportier manner. A gravel frameset may often be a lighter weight option compared to a hybrid bike frameset too, employing higher quality materials that suit the needs of gravel racing and the all-round sportier nature of the discipline.
When we distil down all these advantages of flat handlebars and apply them to competitive scenarios, the end result is a bike setup that distinguishes itself as an ideal machine for disciplines such as Ultra-endurance racing. We can combine component simplicity and durability with flat handlebar comfort and bike control benefits, and for certain races that don’t warrant the need for an all-out mountain bike, this is an ideal configuration.
The potential for an endurance focused handlebar has been realised by the bike industry, and flat-bars such as the soon to be released SEIDO Components Deviation bar embody this potential. The Deviation has an extended 160mm centre clamp section allowing the easy mounting of tri-bars and other accessories essential for grueling endurance events. Input from Sofiane Sehili, renowned endurance athlete and Bombtrack X Seido team rider, influenced the Deviation’s design. Combine the Deviation with a Bombtrack Hook EXT Ti frameset, and what you have is a bike that is versatile, comfortable and quick enough for finding its grizzly way to the top of the podium of the most demanding events.
But let’s try and wrap our heads around how the flat-bar gravel bike concept might fit amongst existing types of bikes. Since the early 1980s, when the first mass production mountain bikes appeared, all-terrain bikes have developed and grown into many different guises. The humble rigid 26er from 40 years ago is a somewhat different beast to the hi-tech enduro 29er machines that we see today. Mountain bikes have become a finely tuned piece of equipment that allow the rider to tackle trails that would have seemed impossible to ride back in the 80’s – long travel suspension forks and complex linkage systems smooth out the trail and make the rider feel like they are gliding over technical terrain on a magic carpet. The advancements in technology can make off-road riding more accessible to riders of varying skill levels, and allow the most experienced riders to push themselves even further. However, there is no denying that the spirit of mountain biking has developed alongside the progression of mountain bike design. We have seen mountain biking transition from an adventure focused discipline to more of an extreme, adrenaline fueled sport, where often the focus is on getting from A to B in the fastest, gnarliest way possible, instead of exploring places more remote, or more difficult to access on a conventional bike. Of course there is nothing wrong with this, and the progression modern mountain biking has taken is natural, but for a long time there seemed to be a void in the mountain bike world where early mountain bikes used to live. The simple, robust machines of the ‘good old days’, with field serviceable components and bomb-proof steel frames have given way to the 21st century versions – it is no surprise that many adventure cyclists today opt to ride 80’s or 90’s mountain bike frames when spending months or years on the road. There are also touring bikes on market today that basically emulate the specification of early mountain bikes. It is clear that the same thirst for adventure orientated off-road riding that was tapped into 40 years ago still exists, and maybe that is one reason why we have seen the gravel bike boom happen. But perhaps there is a more simple reason for this resurrection of the rigid off-road bike. It comes from the same reasoning that cyclocross is still so popular – underbiking is fun and the challenge that comes with it is still very appealing to many riders.
There are still retro mountain bikes available to buy; second hand and NOS (new old stock) examples saturate the market. But often they are expensive and finding the right spares can be challenging. The flat-bar gravel bike could be the solution that promises to scratch the itch that only a rigid ATB can scratch. Arguably, it will do everything, and more, that a retro MTB can do. A 650b wheel versus a 26 inch will handle rough terrain more efficiently, and up-to-date component standards on a modern gravel frame mean that we are not limited to rim brakes and archaic hub width standards. We have also seen a noticeable improvement in material quality, not to mention the introduction of carbon fibre and its increase in strength and workability, making it a super versatile material that is used in the fabrication of many gravel bikes. Both new, and also highly developed traditional materials, bring the concept of the flat bar all-terrain bike into the modern age, and allow us to refine that part of the spirit that was sought back in the early days.
But the flat-bar gravel bike isn’t all about hunting for nostalgia. We can use the gravel frame and flat handlebar combination to facilitate the choice to run and use a selection of up-to-date drivetrain components. Essentially, it can be difficult and costly to find ways to use mountain bike parts with drop-handlebars. An STI or road brakeset is generally a pricier option when compared to a mountain bike brakeset combined with a shifter. We would also be somewhat limited when it comes to the number of pistons in the brake caliper when speccing out drop-bar shifter/ brake setups. Using a flat-bar configuration may also allow us to mix and match between brake lever and shifter brands. For example, a rider may have the freedom to choose to run a Shimano brake setup with a SRAM drivetrain system, and vice-versa.
So maybe the flat-bar gravel bike isn’t necessarily a new concept, but instead it picks up where mountain bikes left off in the 90s, and heads down a slightly different avenue. They are an accessory for adventure, with practicality at the core, allowing for a good helping of high-end race performance. They can be race-ready machines for some of the most demanding events on the race calendar, that will then double up as dependable commuters mid-week. Where the rider needs versatility without any compromise, the flat-bar gravel bike could well be the perfect solution.
SEIDO Components
July 2025
By Peter Skelton