Posted at: May. 16, 2022
A valve extender, which extends the valve, is an essential item for operating deep-rim wheels on road bikes and other vehicles. The following is a summary of the different types of valve extenders, their differences, and how to select one.
Table of contents
Sponsored Link
A valve extender is an accessory used to extend the length of the valve on a tube (or tire in the case of tubular tires).
On normal wheels, this is not necessary because the valve is long enough, but on deep-rimmed wheels, the valve must be extended due to the height of the rim to connect the valve to the inflator.
Valve extenders solve these problems.
There are several types of valve extenders based on the method of attachment to the valve.
In the “Interlocking type”, the valve core is removed from the valve, the extender is inserted in place of the valve, and finally the valve core is attached. It is called “jointing” because it is simply extended.
The Kabusei-shiki type is used by covering the valve from the top, while the valve core remains attached to the valve. Since it is installed by loosening the screw at the end of the valve, if the extender and valve are incompatible, air will escape.
The synchro type (also called synchro extender) is also covered in the same way, but the extender itself has the same function as the valve core because it has a push pin at the tip of the synchro extender to release air.
So which type of extender should you choose?
Here is a comparison of each type.
| Type | Valve core | Special tool | Adjustment of air pressure |
|---|---|---|---|
| Interconnecting type | Need to remove | Necessary | Possible with extender |
| Covered type | No need to remove | Not Required | with extender removed |
| Synchronization type | No need to remove | Not Required | Possible with extender |
The first point is whether the valve core can be removed. The valve core must be able to be removed to use the joint type, but both the cover type and synchronized type can be used even if the valve core cannot be removed (even if the type can be removed).
Next is whether or not a special tool is required. Again, the joint type requires a special tool to remove the valve core, but the cover type and synchro type do not require a tool because they are simply inserted into the valve threads. For the joint type, the extender often comes with a tool, so this is not a problem, but it is necessary to carry a tool for repairing a puncture.
As for adjusting the air pressure, the joint type, which can use a valve core, and the synchronized type, which has a piston at the tip, can be easily adjusted. On the other hand, in the case of the cover type, the air pressure cannot be adjusted with the extender, so the valve core is used to adjust the air pressure. Keep in mind that it is difficult to adjust the valve core if it gets stuck in the rim.
How much to extend the valve depends on the height of the rim and the length of the valve, so manufacturers sell valve extenders in a variety of lengths.
are the major ones.
When selecting a valve extender, first check whether the valve core of the tube (or tire in the case of tubular tires) to be used can be removed. In many cases, this is not mentioned in the specifications of the tube or tire, but it may be mentioned in user reviews, so use that as a starting point, or contact the retailer for more information.
Next, check how much extension is needed. The length to be extended is
The length of the valve can be calculated approximately as follows: “(rim height + 30mm) - length of the valve.
The extra 30mm is the margin for connecting the valve to the inflator.
For example, if you are using a 40mm valve tube on a 50mm height semi-deep rim wheel
(50mm + 30mm) - 40mm = 40mm
so you would choose a valve extender that extends the valve by 40mm.
After all this has been decided, the last step is to decide on the installation method.
If you choose a cover type or synchronized type, you can remove the valve extender and operate it, or leave it installed and simply replace the extender by hand if you get a flat tire. However, if the valve and extender are incompatible, the valve may be pushed inside the extender, causing air to escape.
The advantage of the joint type is that it can be fixed firmly and has almost no compatibility problems, but its disadvantages are that you need to choose a tube whose valve core can be removed and you need to carry a tool. However, the relay type is the most reliable and can be used with confidence.
Which is better depends on the tube/tire and wheel you are using, so try to find the standard and method of operation that suits you best.
Sponsored Link
Tubeless is reassuring to have! Summary of air pumps with booster/boost function
The booster simplifies bead raising, which is the most difficult part of tubeless installation. We have compiled a list of air pumps with booster(boost functions) that are reassuring to have one.
What is hookless rim? Advantages, Disadvantages and Points to Consider When Choosing
Many "hookless rim" wheels are lightweight and cost-effective. What is hookless? We have compiled a list of advantages and disadvantages of hookless, as well as points to keep in mind when choosing.
What is the ASTM standard for bicycle wheels?
What is the ASTM standard for bicycle wheels? We have compiled a list of points to note when choosing a wheel.
What to do when you get a flat tire with a tubeless or tubeless ready tire
Tubeless tires have seen a dramatic increase in the number of users over the past few years. Even with tubeless and tubeless ready tires, punctures cannot be reduced to zero. The following is a summary of the causes of punctures and how to deal with them.
How to check compatible tires from wheel specs
When trying to change tire thickness on a road bike or other sport bicycle, it is important to know what tire size the wheel will allow. In this article, we will show you how to find out which tires are compatible with your wheel based on its specifications.
What is a tubeless valve? Types and How to Choose
The tubeless valve is an essential item for tubeless use. What is a tubeless valve, tubeless valve types, and how to select one are summarized below.
What is SRAM's XDR and XD? What is the difference from Shimano?
The following is a summary of SRAM's proprietary XD and XDR standards, what makes them different from Shimano's, and what to look for when purchasing.
Summary of Shimano wide ratio sprockets for road bikes
Shimano wide-ratio sprockets for road bikes are listed here, including compatibility by step number.
Summary of 12-speed chains for use with Shimano road bike and MTB components
We have compiled a list of 12-speed chains that can be used with Shimano road bike and MTB components. Also about chain compatibility with chains from manufacturers other than Shimano.
Types of bicycle disc brake mounts, how to recognize them, and how to choose an adapter.
Mounting adapters for bicycle disc brakes are essential when changing calipers with different standards or rotor sizes. This section explains the types of mount adapters, how to recognize them, and the model numbers of Shimano's mount adapters.
Inside, outside serrations? Types of center lock locking rings
There are two types of lock rings for center locking disc brakes, inner serration and outer serration. The following is a summary of the differences and how to select the right one.
Summary of mechanical disc brake calipers for road use
Mechanical (mechanical) disc brake calipers are ideal for ease of maintenance and as an upgrade from rim brake components. Models from major manufacturers are listed below.
What is a Through Axle? Types and How to Choose
Through-axle is becoming a major fixation method for disc brake wheels. What is a through-axle? Here is a summary of what types are available.
Difference between 700C and 650B, advantages and disadvantages
With the popularity of gravel road bikes and the spread of disc brakes, the choice of road bike wheel size has become not only the standard 700C, but also 650B. In this issue, we will look at the differences between 700C and 650B, and the advantages and disadvantages of each.
Types of disc brake rotors and how to select them
Disc brake rotors are an unassuming part, but they have a significant impact on the effectiveness of disc brakes. We have compiled a list of the different types of rotors, how to select one, and the lineup of rotors from major manufacturers.
Disc brake pad types and selection
Brake pads are installed on the calipers of disc brakes. In fact, there are multiple types in terms of material and shape. The following is a summary of disc brake pad types and how to select the right one.
Summary of hex wrench sizes to prepare for road bike maintenance.
For those who will be servicing their road bikes, we have compiled a list of hex wrench sizes that are commonly used for road bike maintenance and that you should have available.
Latex Butyl? Different tire tube materials and how to choose the right one.
There are two types of bicycle tire tubes, latex tubing and butyl tubing. The following is a summary of the differences between the two and which one you should choose.
Guide to Choosing Binding Pedals for Road Bikes
Binding pedals allow you to ride faster and more efficiently on your road bike. In this article, we will thoroughly explain what to look for when choosing binding pedals.
Summary of binding pedal cleat types and their respective characteristics
Cleats are the parts that connect binding pedals to shoes. Cleats are only one part, but each manufacturer has its own characteristics and differences. They are actually important parts that are linked to usability and their merits and demerits.