Here’s how to mount an additional battery, also called a range extender, for the Mahle X35 motor.
The Mahle X35 motor is one of the most widely used hub motors by bicycle manufacturers in recent times. Especially on lightweight city bikes, gravel bikes and electric racing bikes. This motor has many advantages; however, its autonomy is limited, which might bother some of you a little. In most cases, the motor is equipped with a battery integrated into the down tube.
This has a capacity of 248 Wh, enough to ride around a hundred kilometers. Of course, it always depends on the profile of the route, the type of terrain, the level of assistance used, etc. A range that some of you may consider too limited. However, thanks to the Mahle X35 range extender you will be able to have an additional power of 208 Wh, which is equivalent to a remarkable 70% of the capacity of the main battery integrated in the tube. Enough energy therefore to be able to easily extend your outings.
Contents of the installation kit
- The battery and its support that we will attach to the frame.
- A small rubber tab that will secure the battery and prevent it from slipping off the support.
- The battery integrates the cable for the socket located in the frame. Practical and smart.
How to install the Range Extender X35
- Before using the range extender, first detach the cable from its mount and pass it through the small opening, so that you can easily plug the connector into the charging socket integrated into the frame.
- In the Mahle app we now see that the integrated battery is almost fully charged and displays a range of 121 kilometers without the additional battery. Let’s see what will be displayed after installing the range extender.
- The charger is plugged into the top of the battery, into its socket. You can therefore connect this charger and charge your battery wherever you want, in your apartment, garage, etc.
- First, we will unscrew the screws of the bottle cage on the down tube. The bike moves a little, as you can see, and the handlebars turn around. This happens quite often when the bike is on a work stand, as is the case here. To fix this, you can simply tie two rubber bands together, passing them around the valve and then around the frame, see images below.
- When removing the screws from the bottle cage, we found that the ones that came standard were very short and would not be suitable for mounting the Mahle range extender bracket. So we bought slightly longer screws. You may need to do the same. Be aware that 10 millimeter screws are more than enough. It is advisable to carefully measure the thread, length and pitch, checking whether the head of each screw is countersunk, flat or round, avoiding wood screws, in order to buy completely compatible screws from one of the many online screw shops, or DIY stores. To calculate the pitch, divide the length of the thread by the number of threads. For example, if a screw has a thread length of 10 mm and 5 threads, the pitch is 2 mm.
- To get an idea of the optimal position of the support, do not hesitate to present it on the frame and test different options. We have an intermediate position because the cable comes out here, because there is the charging socket at the bottom and because the cable is not very long. But we should be able to make the connection without problems.
- Monté dans une position intermédiaire
- Elles sont hélas trop courtes !
- Enlever les vis du cadre
- Now let’s take the two screws that we bought. The first one will allow us to roughly place the support without tightening too much. With the second one we will fix everything. Tighten the two screws well.
- Then take your battery and place it in the support. Pay attention to the cable passage. Insert the battery from the side and turn it slightly. The cable passes correctly at the bottom. Under the bottle cage, there is also a groove in which the cable can pass.
- Inserting the connector into the charging socket is a little tricky. To make it easier, take a few moments to look at how the connector is made. Then match its insertion into the charging socket so that it fits perfectly. Then lower the safety ring and turn it so that it engages. Once the connection is secure, the Mahle range extender is connected.
- Now that the battery is installed, you can turn the bike on. It takes a few seconds for it to connect to the app. You see that it is now connected and we see the same display as before.
- Now turn on the additional battery which is immediately recognized in the app, in order to see the remaining capacity of the range extender, and the remaining capacity of the main battery, which is integrated in the down tube. But unfortunately we no longer see the estimated range in kilometers. This is one of the small drawbacks of the Mahle app.
- Finally we will place the small rubber tab on the range extender holder. This will secure the battery when you ride.
- Match the connector insert into the charging socket
- Turn on the additional battery
- Place the small rubber tab on the range extender support