In the world of high end bicycles, there’s typically a huge gap between stock, mass production bikes and the one-off custom bikes made by a single builder. Italian startup Exept is offering something in between, letting you choose from set options and shapes, but still get full custom geometry informed by reams of data to help you get the right fit. The result is a custom carbon monocoque bike, purposed built for you and your drivetrain, all hand made in Italy. We covered their launch announcement and showed a bit about their build process, now we’ve got more details on how their fit system works and the options available.

The process starts by choosing the type of bike you want. As of this post, only the All Road model is available, the Aero frame comes later this year. Then you work through the other options, building your bike to suit your riding style and preferences. Step 4 is when you pick the component group, drivetrain and wheels to suit your budget, but they’ll all be disc brakes. They’re not making a rim brake version.

You can create an account and save your progress, so you can always come back to it. The real cool feature is that you can input your body measurements (you’ll need a friend to help measure, or get a professional fit done) and it will show you your ideal frame geometry spec. It’ll even flag you if a number is too far out of range so you can go back and double check your measurements. Here’s what all the options look like, and how they came up with their geometry recommendations…

Exept custom monocoque carbon fiber road bikes use a unique sizing system to deliver the perfect fit and geometry

The All Road model looks like a modern road bike. It’ll have 35mm of space for the tires at the fork and stays, so they recommend a max 30mm (measured, actual) wide tire. It’s not a gravel bike, but that is a model they’re considering for the future.

Exept custom carbon fiber road bikes from Italy are disc brake only but available with race or endurance geometry

Regardless of your other choices, you’ll get a pressfit BB with rectangular chainstays and a wide bottom bracket shell to maximize power transfer.

Exept custom monocoque carbon fiber road bikes use a unique sizing system to deliver the perfect fit and geometry

And thru axles front and rear. Note the lack of holes in the back? That’s because this show bike was made specifically for SRAM Red eTap.

Exept custom monocoque carbon fiber road bikes use a unique sizing system to deliver the perfect fit and geometry

When it’s all said and done, your seat tube will be marked with the stack, reach and actual frame weight of your personal frame. We’ll be visiting their factory this fall and show more detail on their process then, but the short of it is this: Traditional monocoque bikes are made in fixed molds. Exept uses flexible but firm silicone molds on the inside, with adjustable metal molds on the outside. Within a reasonable range, they can adjust the metal molds to fit your geometry numbers, then fix everything in place so that the construction mimics a normal monocoque frame.

Exept custom monocoque carbon fiber road bikes use a unique sizing system to deliver the perfect fit and geometry

Next, you get to choose if you want the Integrated frame or Classic. Above is the Integrated version, which slams the stem and includes the Ursus handlebar/stem unit. This is the cleanest looking option as that system hides the cables and hoses by running them through the stem and directly into the frame. This way, they can remove the holes from the  headtube area.

Exept custom monocoque carbon fiber road bikes are available with standard or integrated bar stem and seatpost designs

The Integrated model has a thinner downtube, so there’s slightly less torsional stiffness, and it’s a bit heavier. But it does look better, so it depends on what you’re after. The Classic model (on left) uses a traditional headtube, headset and stem and will generally be about 5% lighter than the Integrated.

Exept custom monocoque carbon fiber road bikes use a unique sizing system to deliver the perfect fit and geometry

The Classic model (left) uses a traditional round seatpost, while the Integrated (right) gets a different seat tube and custom seatpost with a flat back so it has less aft flex.

Exept custom monocoque carbon fiber road bikes use a unique sizing system to deliver the perfect fit and geometry

The last step before inputting your measurements is choosing between Race or Endurance geometry. Race frames (shown on the left) have 410mm chainstays, which is as short as they can make them and still have everything fall within recommended chainline/distance guidelines for good shifting. work with disc brakes, 410mm keeps chain line ok. Chainstays are 10mm longer for Endurance frames (on right).

Exept online bicycle geometry program lets you custom configure the best bicycle geometry and fit for your new custom bike

Which drivetrain group you choose will dictate some of the frame features. Pick eTap and you’ll get an extra water bottle boss (right). Choose one of the other electronic groups and you’ll get an integrated junction box holder (left). Or just have them add a dummy space for it if you think you’ll upgrade to a wired electronic drivetrain in the future (center).

Cockpit choices affect the frame, too. Pick the Shimano Pro bar and stem and you’ll get a little more integration than if you choose the ENVE bar and stem, which have no channels for hiding the cables and hoses.

How Exept Determines Frame Geometry

The engineers and founders used Zedler frame stiffness results from 800 different frames over the past few years to get a baseline for desired stiffness at key points in the frame. That let them build a computer model and test layups and materials virtually. Using aerospace simulation tools, they created virtual layups and simulated stiffness tests via FEA until they got the frame the way they wanted. Then they built real test frames and compared the results to get their data correlated and validated. Now, when they need to make adjustments virtually to tune the layup for a specific customer, they’re confident that the results will match the end product.

Once they have your measurements, they work backwards to get stack and reach, then the head angle and trail and rake. They measured me while at the show, plopped in the numbers, and we ended up within a few millimeters of most of the road bikes I ride, which is impressive. If you really want something different, you can force change a number or discuss options with them, but their numbers are based on what’s been proven to have good handling and ride characteristics out in the real world. As for their ability to translate that through the layup, we’ll find out later this year. They’re building a bike for us to test long term, to be delivered this fall. Stay tuned…

Exept.cc

9 COMMENTS

  1. Despite what they claim, this seems to be some sort of fancy tube-to-tube construction. Not that there’s anything wrong with that, but if it’s a duck, call it a duck.

    Prices? I don’t like it when companies obscure prices either.

  2. Hello Velokitty
    It is not tube to tube tecnology but a proprietary EXEPT patented manufacturing process. A cut frame was shown at EB so that anybody could check the continuous carbon structure without use of filler or non structural material.

    Concerning the prices, pease go through the configurator, pick your spec, design your frame and you’ll get the price in the summary page. You are quite right, we should show prices in a more evident way, thanks for your suggestion, we’ll surely improve this.

    • Just to address the question I asked below directly to you Alessandro, is your system a full monocoque right from the start, or is it a modular monocoque with several monocoque pieces that are then joined together after curing? Unfortunately I didn’t have the benefit of going to Eurobike so i couldn’t see them in person. Either way, I’m sure your frames are sweet.

      • Hello TheKaiser, thanks for your question as it casts a light on the core of our proprietary technology. No, it is not what you define “modular monocoque” as we don’t bond together pieces cured in a previous manufaturing process phase. The process is what in aerospace industry is referred to as “co-moulding”. Some of the components are partially pre-cured and then cured again together with others, so that the bonding material is actually the resin itself, no glue at all. This enables the plies (whose the structure is made of) to concur to the frame stiffness all in the same way. The so-called load path does not have to jump out from a tube, pass through a softer glue to run through the joint and finally reach the other tube.
        More than this, while curing the carbon structure is always leaning against an outer tool surface throughout the whole process: this lets us use high inner pressure values to get a more compact structure. This is not possible if the pressure is applied to the outside as the structure will buckle above certain pressure values.
        The structure is hence continuous and all made up of carbon fibres and resin, that is why we can design the frame carbon structure in order to achieve (and mostly overscore) the stiffness and weight of the best stock monocoque frames out there. If you wish to know more just drop us an email (info@exept.cc) and we will forward you a close up of the cut frame we showed at EB

  3. Hi VeloKitty, no it is actually not tube-to-tube. We had a cut frame at the show demonstrating the internal monocoque structure. Feel free to contact us via our webpage If you like to hear more about it.

    • Would it be more accurate to call it a “modular monocoque”, where a few separate monocoque pieces are then bonded together after curing, or is the entire frame truely assembled and cured as 1 piece? Not that there is really anything wrong with doing it in a modular fashion, in fact it has some advantages in terms of being able to ensure all surfaces achieve optimal compaction, but in the interest of truth in advertising it would be good to know if the monocoque is modular or not, as some people don’t even realize that modular is a thing, and may assume it’s “tube to tube” if the see a seam.

      • agree with you TheKaiser. As explained here: http://www.egocycles.com/technology-explained by Exept guys, these are tubes post-cured together with other fiber at joint. No glue but just the resin of the joint area that is cured on the already formed tubes (that I will imagine will be cut at dimension). So almost the same operation every artisans, like Sarto, do. You will do from internal side ok! But not call it monocoque. Otherwise you don’t say the truth to people that don’t understand what they are buy. your, It’s a single piece but no continuos fiber between tubes if were needed.
        As I tryed to explain in other post, at this point I will call my steel frame a steel monocoque, is it fine for you?

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