Table of contents
How to choose a frame that won’t give you trouble when building a road bike from scratch.
Let’s check the size carefully.
When you build a road bike from scratch, you will most likely be looking for the frame alone. As you can see when you are choosing a frame, it is very difficult to know what size you are looking for when you look at the frame alone.
Bicycles that are the wrong size are not only difficult to ride, but can also lead to an accident, so make sure you choose a frame that properly fits your body.
If the bike is originally a complete bike, search for it by the name of the complete bike and check it carefully because the geometry is often still available on the official website.
Choose the right frame for your purpose!
There are three major types of sports bicycle frames as follows
- for road
- for MTB
- for cyclo-cross
Each type of frame has different end widths and brake mountings, so if you don’t choose the right frame for your purpose, you will have a hard time choosing the right parts.
Also, if the frame is originally a cross bike frame, be aware that some frames are more road-oriented and some are more MTB-oriented. MTB-oriented frames tend to have V-brake pedestals for brakes, so check that area.
Choose a frame with many common standards
The higher the price of a frame for a road bike, the more likely it is to have its own standard. Small parts may not be available, and even if they are, the parts alone can be quite expensive.
The following are five of the most common proprietary standards. 1.
- seat post shape
- clamp shape
- wire routing
- head tube shape
- derailleur mounting (hanger)
If the shape of the seat post and derailleur is special, you will be stuck at that point if small parts are not available.
In this sense, it is safer to choose a frame with common standards for these parts, because the parts can be substituted.
Points to keep in mind when choosing a frame
End width and clearance
For road use, the standard is 100mm for the front and 130mm for the rear. If this is not the case, your wheel choices will be limited, and you may have trouble adjusting the shifting due to the change in chain line.
Tire clearance is also important. Frames designed for disc brakes often have a large clearance, while older models of road bikes designed for rim breaks often have a clearance limit of about 25C.
Be especially careful if you want to choose larger tires such as 28C.
How to install the brakes
Just as important as the end width is the way the brakes are installed.
There are four main types of brakes for sports bicycles.
- direct mount
Rim and disc brakes are the most common for road bikes, while V-brakes and disc brakes are the most common for MTB.
It is important to note that the combination of “STI lever x V-brake” is not recommended by Shimano.
It is not impossible, but the amount of pull on the brake does not match the amount of pull on the brake, so even if you fully grip the lever, you will not get enough braking force. It is best to avoid this combination for braking power.
It is easy to overlook the BB standard.
There are various standards such as JIS 68mm, ITA 70mm, and press fit. If the standard does not match, you will need to replace the BB or even the crank, which can be quite costly.
In the case of road and MTB frames, the column is usually designed for an a-head stem, but there are occasionally cases where a threaded stem is used on a budget road or cross bike frame.
It is possible to use an adapter to convert a threaded stem to an a-head stem, but the choice of parts is limited, so try to choose a frame with an a-head fork.
Cracks in the carbon frame
Carbon frames may have cracks when purchased used.
Cracks can range from a simple balding of the paint to something that seriously affects the strength of the frame, so if you are buying a frame with cracks, be sure to check the condition carefully, and if possible, check with the shopkeeper before buying.