When would you upgrade the drivetrain on a road bike?

When you want to change (or upgrade).

Basically, many people probably follow this pattern.

The reasons vary from person to person, such as wanting to change the mood of the road bike they ride, or because a new product is released, or because a good one was on sale, but since road biking is probably a hobby for many people, “change when you buy” is in a sense correct.

Recently, more and more people are buying used road bike parts, so in some cases, if you cash in your unwanted parts at auctions or flea markets and replace them with new parts, you may be surprised at how little money you have to spend.

When gear shifting malfunctions occur that cannot be fixed by maintenance

Drivetrain parts made by major manufacturers such as Shimano and Campa are often made of highly durable materials, so they do not easily deteriorate or lose shifting performance.

However, if a part is physically damaged, such as by falling off a bicycle, it can cause gear shifting problems that cannot be corrected by maintenance adjustments.

Basically, the replacement of parts is the answer, but many people take the opportunity to replace the entire drivetrain area with parts upgrades, saying, “If I’m going to buy this anyway, I might as well take this opportunity…”.

Insufficient number of shifting gears

Even riders who initially find that an entry-level 8 or 9-speed bike is sufficient, as they train more and go for rides in various places, they will want to have more gear shifting options.

In particular, when a rider is able to cruise at speeds of 30 km/h or more on a cycling road, he or she will want a finer gear shift, such as a gear that allows the legs to rest or a gear that applies a little more load.

Basically, the front chainring and sprocket are used to make adjustments, but in a drivetrain with a small number of shifting gears, a cross-ratio sprocket weakens the low side options, and a wide ratio to strengthen the low side sacrifices fine adjustment.

Thus, if the problem cannot be solved by simply replacing the sprocket, increasing the number of speeds to 10 or 11 speeds will give you a whole range of options.

In addition, with 10-speed, not only the current TIAGRA but also older models of DURA-ACE, ULTEGRA, and 105 can be selected, which has the advantage of expanding the range of replacement parts.

Insufficient supply of parts

In the case of Shimano components, even if they are dropped from the official Shimano lineup, parts have been on the market for a long time. In addition, Shimano supplies replacement parts (small parts) even for old parts, so the service life of the parts can be considerably extended through maintenance.

Nevertheless, if Shimano’s supply of small parts ends, or if they are no longer available in the market, it may be considered time to upgrade the drivetrain.

If the parts are old enough (more than 10 years old) that the supply of small parts has stopped, you are well on your way, and the current model is about two generations ahead of you after 10 years for the same grade, so it is cost effective to upgrade.

When you upgrade your frame.

This is another case where you are faced with the need to replace the drivetrain.

Surprisingly, the same parts cannot be diverted when the frame is upgraded. For example, when upgrading from a caliper brake frame to a disc brake frame, basically the brake area cannot be diverted.

For example, if you upgrade from a W-lever frame to a current frame, you will need STI levers because you cannot use W-levers, or if you change the manufacturer, the BB standard may change.

Of course, when selecting a frameset, you should check the compatibility with the current drivetrain before purchasing, but with current model frames, there are cases where the drivetrain is also upgraded at the same time the frameset is replaced because some standards may not be compatible. However, with current model frames, there are cases where the drivetrain is also upgraded when the frameset is replaced.