Working With a Custom Bike Builder: What the Process Is Really Like (And Where the Fit Comes Into Play)

People often ask about the process of working with a custom bike builder, because they want to avoid mistakes. They read stories on forums about long waits, unclear communication, or specifications that seem to change, and they want to know what is normal, what is not, and how to arrive at the right result. There is no single “correct” process for all builders. Every builder has their own system, I will explain how we work and what riders can consider before they begin.

The Role of the Bike Model

In custom framebuilding, the starting point is almost always a bike model. Custom bike builders develop their own bike models by refining and deciding on tube behavior, carbon type, stratification, direction that will create the handling, and overall character of the bike. These bike models are not templates in the industrial sense. They are complete design concepts that define how the bicycle is meant to feel when you ride.

At Formigli, a new bike model is not created quickly. It is developed slowly, beginning in CAD, then refined through prototypes and experience on the road. Many ideas are tested and discarded. Only when a bike model is fully resolved does it become part of the lineup.

When riders choose a custom frame, they choose a bike model first. The custom work begins in how measurements, posture, and riding style are interpreted within that design.

Where the Process Really Begins

The process begins with two things: The rider, and the chosen bike model. The bike model defines the character and direction. Measurements define how that character is expressed for one body.

Measurements are taken and interpreted within the geometry and intent of the chosen bike model. The bike model’s structural concept is already defined — tube forms, carbon schedule, and fork design are not being reinvented for each build. The custom work is translating a rider’s measurements and posture into the ideal geometry inside that design, and then refining position on the finished bicycle.

How Long Does It Take?

A custom frame takes time, it cannot be rushed.

There are stages that require care. First interpreting measurements within the chosen bike model, working with the rider to ensure the proposed geometry and chosen component lengths and sizes meet their current needs. Next building the frame and finishing it and finally the paint. Some riders request only the frame set to be shipped, others request a full build out with their selected components. Time alone does not define quality. What matters is clarity.

Riders should understand what stage the project is in and why time is being taken. Long waits become frustrating only when there is no explanation. Short waits become disappointing when expectations are unrealistic. Good custom work feels calm when communication is clear.

What Decisions Are Actually Being Made

Because the bike model defines the structural concept — tube set, carbon schedule, and fork — the decisions in the process are primarily about geometry translation, components and  final setup.

These decisions include how measurements are applied to the chosen bike model. What is the intended use (long rides, climbing, aggressive position, endurance comfort). What are the component choices, what are the lengths and sizes available in the part and what is the ideal selection for the client. 

The Fit Bike and the Real Bicycle

This is an important part of the custom process.

A fit is useful. Some riders only take their physical measurements. Some riders choose to both submit their measurements and include professional biomechanic fit data. The fit data can provide good starting points. But it is not the final answer. A fit bike is static. Riders are not moving, not balancing. They are not responding to the forces that act on the body when riding — gravity, inertia, steering input, road feedback, acceleration, fatigue. On a real bicycle, riders balance. Muscles engage differently. The body reacts to motion, not just position. Small differences in front-end height, seat tube angle, fork behavior, and handling can alter posture without the rider realizing it. This is why the true riding position only reveals itself on the completed bicycle — on that custom frame, that fork, that geometry — out on the road.

The body adapts to the actual bicycle on the road

For this reason, the smartest approach is to use fit data as guidance. Then build the bicycle correctly for the rider’s measurements within the chosen bike model. And finish by refining the position on the custom bicycle, in motion, after the rider has ridden it. This is where the position becomes natural, not imposed.

How Riders Work With a Builder

Riders do not need to be experts. What helps most is honesty. Talk about experience, not theory. What has been ridden. What felt good. What felt wrong. What is wanted now. It is also important to accept that not everything can be finalized before the bicycle exists. Custom is not about solving every detail in advance.
It is about arriving at the right solution step by step.

About Communication and Expectations

Most negative stories people share online are not about poor bicycles. They are about unclear expectations. Riders can understand and ask the questions of the builder like- what is defined by the chosen bike model, what is determined by measurements, what will be refined after the bicycle is built? When these boundaries are clear, the process becomes calm.

Closing Thoughts

Geometry and measurements are the starting point. But geometry calculated designed into a bike model does not account for everything. It does not account for dynamic balance. It does not account for how a rider compensates unconsciously. It does not account for how muscles work under load, or how fatigue changes posture. It does not account for handling feedback. This is why final details — saddle setback and tilt, bar rotation, hood position, and sometimes even effective reach — are almost always refined after the bicycle has been ridden. Many builders understand this instinctively. Experienced riders understand it as well. A fit bike is static. A trainer or jig removes balance. The rider is not steering, not making micro-corrections, not shifting weight naturally. A real bicycle introduces all of this. Steering input. Small corrections. Weight shifts. Fatigue patterns that only appear over time. Most riders have felt these differences, even if they have never put words to them. The bike model defines the character. Measurements define the size. The final position becomes correct when riders are on the real bicycle — moving, balancing, and riding. When this is understood, riders stop trying to solve everything too early. And the result is usually much better.