TPU inner tubes are gaining attention as the third force in bicycle tires. We summarize its features, advantages and disadvantages of using it on Road bikes and MTBs, and major manufacturers.
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What is Shimano’s GRX series of components for gravel?
Features of GRX
Shimano’s GRX is a component grade for “gravel road bikes,” a new genre following road bikes and MTBs.
The difference between gravel road and regular road bikes is the expected riding environment.
While road bikes are designed to be ridden on painted roads and MTBs are designed to be ridden on rough roads such as mountains, gravel road bikes are designed to be ridden on both “painted roads” and “some rough roads. It is positioned between a road bike and a MTB.
GRX is a component optimized for such gravel, so it features a good combination of road features and MTB features.
Shimano’s road bike composite currently has seven grades, including DURA-ACE, ULTEGRA, and others.
On the other hand, as of 2021, Shimano’s only gravel component is the GRX grade, and within GRX,
- GRX Di2 (electric component)
- GRX 11 speed
- GRX 10 speed
There are three lines of Shimano gravel components: GRX Di2 (electric component), GRX 11-speed, and GRX 10-speed.
The differences between the three lines are the “number of speeds,” “electric component,” “single front,” and “dropper post operation.” All lines use hydraulic disc brakes, and there are no caliper brakes, which are standard on road bikes, or V-brakes, which are common on MTBs and other types of bikes.
|dropper post operation
|RX-400（Some parts are RX-600 series）
Difference between GRX and composites for road
What is the difference between GRX and road bike components?
- tire size
- compatible sprocket and chainring teeth STI lever shape
The difference between GRX and road bike components is as follows.
GRX supports larger tires than road bikes, wide-ratio sprockets and chainrings, and lever shapes optimized for rough roads.
However, GRX can be mixed and matched with road bike components, and Shimano’s compatibility chart shows that the GRX series is basically compatible with current road bike components as long as they have the same number of gear shifts.
In addition, sprockets and BBs are shared with those for road bikes,
- incorporating GRX parts into road bike components
- incorporate road bike parts into GRX
This means that it is possible to use road bike parts with GRX.
The wide compatibility with road bike components allows for a high degree of flexibility.
Advantages of choosing GRX
A wide range of riding options
All GRXs have hydraulic disc brakes and are compatible with wide ratio sprockets, making them closer to MTB components than to road bikes. However, the riding style is based on the assumption that the bike is used with the same drop handlebars as a road bike, so the riding comfort is that of a road bike, not an MTB.
The shape of the STI lever, compatibility with dropper posts, and chainring spcket gear settings are optimized for rougher roads than road bikes, and the ability to cruise faster on paved roads than MTBs is a major advantage, allowing for a wider range of riding styles.
Front single support reduces shifting problems
GRX is compatible with front single (front single speed), which makes it easy and reduces shifting problems such as chain drop.
In addition, front single is easy to maintain and easy to shift gears, making it easy to ride.
Disadvantages of choosing GRX
Narrow choice of components
Since GRX is still a new “gravel road” genre component, there are only three options in the GRX series, and the disadvantage is that it does not cover a wide range of “entry to pro use” like a road bike.
In terms of parts prices, it is a little below 105 grade, so it is not a grade that hobby users can hardly afford like DURA-ACE, but users who want an entry-level bike may feel their choices are a little limited.
Requires a frame and wheels compatible with disc brakes
All GRX STI levers are hydraulic disc brake models, so the frame and wheels on which they are mounted must also be disc brake compatible models.
Of course, it is possible to integrate GRX into a current caliper brake-oriented road bike to make it gravel-spec, but if you want to have everything GRX, you will need to replace the frame and wheels, and the upgrade cost will be high.
We have looked at Shimano’s GRX.
Gravel road itself is a genre that has been gaining momentum in the past few years, so Shimano’s GRX is in a sense “the grade of the future”.
There is a lot of freedom in customization, such as turning a road bike into a gravel spec bike, or having GRX components from the start, so we are looking forward to the future.