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6 Things You Need to Build a Complete Road Bike

Purchasing a new bike from one of the numerous factory-built motorcycles offered by dozens of companies is the most practical option. These off-the-shelf products are quite affordable, and potential customers may test the bike before choosing. But the buyer has no input over the choice of parts or the color of the frameset. This is something you can only do when building your bike.

To build a complete road bike, you’ll first need a frameset, keeping in mind the individual components. Then, it’s time to choose the fork, bottom bracket, crank, seat tube, groupset, and all components at the points of contact.

Before we discuss this further, let us talk about whether it’s cheaper to purchase a bike or build it yourself.

parked road bike

Is It Cheaper to Build Your Own Road Bike

Generally speaking, if your budget is less than $1000 or even $1300, you will receive a far better value by purchasing a built bike, particularly if it’s a model from the prior year. Building a bike yourself makes sense if your budget is far more than that.

99% of the time, buying a pre-built bike will be less expensive than doing it yourself. Why is this so? for several reasons.

First, the bike industry is extremely competitive. Although there are relatively low margins, the market is nevertheless very large. However, selling certain components is a specialty industry where margins are greater. What’s the outcome? For instance, a groupset bought separately will cost 30–40% more than the identical groupset mounted on a whole bike.

Second, manufacturers purchase thousands of sets of these parts in bulk quantities. Shimano, SRAM, and Campagnolo are three of the major producers of important components; as a result, the rate they receive from one of them is far less than what individual retailers can charge you if you purchase the same parts independently.

How to Build a Bike Step by Step

In this section, we’ll describe what you’ll need to build a road bike step-by-step. Keep reading below to find out!

For more detailed instructions on how you can build your own bike, watch this video below:

The Frameset

The frameset is where any construction should logically begin. It serves as the foundation of the bike and acts as a model to direct construction. It is much simpler to choose bike components that fulfill the requirements of a frameset rather than the other way around since many bike parts lack standards and have a limited number of possibilities with minimal redundancy.

Another important advantage of starting with the frame is that doing so gives the consumer the most freedom to select the ideal frame size and suitable geometry. This is possibly the most compelling argument in favor of bespoke construction since it allows the consumer to select a frameset that they know will meet their requirements.

Finding potential candidates by looking through internet geometry charts for standard framesets shouldn’t be difficult for riders who have a strong awareness of their position, fit, and handle tastes. Additionally, detailed specs are frequently included so that potential customers may compare all of their alternatives before deciding which one to choose.

A custom frame can be a better option for people who have unique demands. A frame builder will be able to create a frameset that not only precisely fits the consumer, but also takes into account any preferences the customer may have for the overall design (such as a sloping vs straight top tube) and particular parts. 

The client frequently has the discretion to decide on the frameset’s features, such as the fittings for extra bidon cages, fenders, and/or racks.

Keep the Components in Mind

Road bikes have expanded in variability in recent years, resulting in specific models that were developed for off-road riding, convenience, varied terrain, and aerodynamics. Disc brakes, 1x gearboxes, and electronic shifting have all been introduced at the same time, leading to a variety of specialized fittings with minimal overlap or interchangeability. 

For instance, it is impossible to change a frameset from rim brakes to disc brakes (or vice versa), and it is also impossible to add the ports needed to internally channel the wiring for an electronic groupset to a frame that already has fittings for mechanical derailleurs. 

Therefore, it is virtually impossible to choose or purchase a frameset without first considering the other parts that would be required to finish the project.

The Fork

Many purchasers won’t have to choose the frame’s fork. This is especially the case with modern carbon framesets, in which the fork is frequently integrated into the structure of the frame, and it may not be possible to utilize a different brand or model. 

The rider has more choices with frames made to order or with a standard head tube and axle-to-crown measurement.

Most aftermarket road forks are constructed of carbon fiber, and although there are some aesthetic variations, purchasers should only focus on one major aspect: the degree of rake, which will influence the bike’s handling and the level of contact with the front wheel.

In this situation, it’s important to note that even small changes to the fork rake can change the way a bike turns. To produce an appropriate amount of steering trail, frame builders always plan the frame’s geometry based on a particular fork rake, so customers should be aware of both before taking on this task.

Specifications for the Key Frame and Fork

Although there are no set standards for frames and forks, and some components, like bottom bracket shells, appear to change with time, there are still only a limited number of discrete possibilities. 

Because of this, an expert eye (like that of a mechanic) may be able to figure out some of the parameters. Otherwise, a vernier caliper will be needed to measure the internal and/or external diameter of the head tube, fork steerer, bottom bracket shell, and seat tube.

The Bottom Bracket and Crank Compatibility

With road bikes, there are roughly a dozen distinct bottom bracket designs, and when off-road bikes and fat bikes are included, the variety only increases. It may be broken down into two general categories, threaded and threadless (or press-fit), which are additionally separated according to the internal diameter and shell width.

When constructing the bike, fitting the bearings to the bottom bracket shell is only a single part of the puzzle since they also need to fit the cranks. There are currently no set regulations, and the internal diameter of the bearings should fit the diameter and design of the crank axle. 

Instead, the majority are exclusive designs available only from particular companies. While those companies may provide complementary bearing sets, none are equipped to accommodate all of the bottom bracket shells now in use.

The Seat Tube

The front derailleur and saddle both depend on the seat tube’s specs. As with the former, most frames contain a seat tube within which a seatpost is placed to connect the saddle. In this case, the size (and form) of the seatpost is determined by the seat tube’s internal diameter (as well as shape). 

Although there are a few standard seatpost sizes, such as 27.2mm and 31.6mm, there are many other options, and they all need to be properly matched (e.g., a 27.0mm seatpost cannot be used for a 27.2mm post).


For many purchasers, a groupset—which includes all of a bike’s shifting, braking, and transmission components—is the most practical and economical method to get the bulk of the parts needed to finish a customized build. 

Shimano, SRAM, and Campagnolo are the three main manufacturers to pick from, and each has a variety of choices to fit various setups and price ranges. A smaller variety of groupsets or transmission/braking components is offered by other companies such as Rotor, FSA, Miche, SunRace, and MicroShift.

In a nutshell, a groupset needs to meet two types of requirements: firstly, it must adhere to the requirements for the frameset so that each of the components can be installed; and secondly, it must meet the demands of the cyclist, which may be dependent on weight, performance, and/or price.

Points of contact

While selecting a handlebar, stem, saddle, and pedals for a custom bike is mostly a matter of taste, there are some considerations to make:


First of all, the stem should work with the fork of the bike. A threadless fork needs a threadless stem, while a threaded fork needs a quill stem. In both situations, the fork steerer’s diameter is crucial; however, for quill stems, it’s the internal diameter (22.2/25.4/28.6mm), and for threadless stems, it’s the external diameter (1 in./25.4mm, 1.125 in./28.6mm, and 1.25 in./31.8mm).


As was already noted, the handlebars should fit the stem’s clamp diameter. The bars’ total width, as well as their reach and dip, are the remaining crucial parameters. While individual taste (and maybe flexibility) can play a part in determining the degree of width and drop for the handlebars, the selection of each mostly relies on the rider’s fit.


Choosing a saddle is a very subjective decision. The overall breadth and shape of the saddle affect how well it fits, but there is no quick method to determine a good match without experimenting with it.

The dimensions of the saddle rails must be taken into consideration. Carbon rails feature a 7x9mm rectangular cross-section, whereas all-metal rails have a 7mm diameter. A new set of fittings will be needed for carbon rails with certain seatposts (such as those made by Enve and Specialized, as well as Trek seat mast toppers).


As previously indicated, the internal diameter of the seat tube should be perfectly matched for frames that employ a flexible seatpost. The length and degree of offset for the saddle clamp on posts may differ. 

The degree of the offset will determine how many setbacks could be supplied for the saddle, and frames with a sloping top tube would need a longer post (up to 400mm) than those with a horizontal top tube. 

For riders who require a bit of saddle setback, a post with a 25mm offset will be preferable to a post with zero offsets, but the decision will ultimately depend on the angle of the seat tube.


The selection of a pedal is mostly a question of taste. All road cranksets have a single thread size, but some manufacturers (like Shimano and Speedplay) provide extended axle lengths for riders that want a broader stance.


The wheel fittings for road frames remain mostly stable in comparison to other components of the bike, such as the bottom bracket, although there have been a few alterations in recent years. Modern road frames (with rim brakes) and forks can accommodate 9 mm quick-release axles with 100 mm front hub spacing and 130 mm rear hub spacing. 

The spacing for the rear hub used to be 120 mm (5/6-speed) or 126 mm in former times (preceding the 8-speed era), resulting in the sole change (7-speed).

Road cyclists can choose among three tire systems: clinchers, tubulars, or tubeless tires. Although clinchers and tubeless tires can be interchanged to some extent, the selection of a tire system largely depends on the rims.

There are a lot of different tire brands and models to choose from, and customers must pay close attention to both the wheel’s diameter and the tire’s width. Most modern road framesets can accept tires up to 28 mm wide, although some older road framesets may have had tire clearance as low as 23 mm. 

For bikes with disc brakes, particularly all-road, cyclocross, and gravel bikes, this may be more of an issue.

Putting Everything Together

The logical plan of action for putting the bike together when all the parts have been gathered (or delivered) is to locate a reliable mechanic. It would be worthwhile contacting around and obtaining a few quotations first as many bike shops won’t accept a new client with a package full of parts obtained from internet sources. 

As an alternative, look for a service-only establishment where you can speak with the professional who will perform the job for you; you may even be able to observe how the bike is made.

Final Thoughts

In general, constructing a bike from scratch is not a tough task. After all, there are only a relatively limited number of components, and a thriving sector offers a wide selection of goods to meet different demands. Since online shopping and easy access to international dealers have made the world smaller, the only big problem with getting parts for a custom build is knowing what each part of a road bike needs.