All current Aventon bikes come equipped with disc brakes as opposed to rim brakes. Disc brakes are more effective in a variety of conditions and can be more responsive (especially hydraulic disc brakes. Our Soltera 7, Soltera 2, and all Sinch models come with mechanical disc brakes. Mechanical disc brakes mean that the caliper is actuated by pulling a cable. Every other model includes a hydraulic disc brake setup which means that the caliper is actuated using the force of hydraulic fluid in the brake hose to push the brake pads when the lever is pulled, just like a car or motorcycle. Hydraulic brakes provide superior stopping power and are preferred on higher-end applications.
Excessive Brake Noise/ Contamination
If you are experiencing excessive brake noise, sometimes brakes need to be broken in by being properly bedded. The bedding process is shown below this section. Most Aventon bikes come equipped with metallic brake pads. By nature, metallic brake pads have better stopping power at the expense of being noisier. Resin and organic compound brake pads will usually run much quieter. Another cause of squealing or noise could be caused by some contaminants on your brake rotors or pads. Cleaning the brake rotors and brake pads with 91% rubbing alcohol and a clean towel can remove most fresh contaminants. Lightly resurfacing your brake pads with sandpaper can also help remove that first contaminated top layer as well.
This short video is a great example of steps that can be taken to remove contaminants: https://www.youtube.com/shorts/GomGfiAnRqY
If the cleaning process does not achieve the desired result, it is recommended to replace both the brake pads and rotors of the affected brake at the same time.
The video below is a general guide on replacing brake pads:
https://www.youtube.com/watch?v=Xqw0SaZl-jo
Changing Brake Pads
Brake pads on your ebike will need to be replaced in time for a variety of reasons, whether it's from standard wear and tear or from contamination. The effectiveness of your brake pads can and will deteriorate if they are contaminated or worn out. Luckily, replacing brake pads on an ebike with hydraulic disc brakes can be as simple as a DIY or a visit to your local bike shop!
Quick Tips
- A healthy brake pad material must be a minimum of 1 mm thick (the equivalent of 3 stacked business cards). Any thickness less is a sign for a replacement.
- It isn't easy to spot contaminated brake pads with the naked eye. If your brakes squeal or squeak or your rotor appears to be a darker color with oil smears, it's a sign that your brake pads may be contaminated.
Finding Replacement Pads
Purchasing the correct set of brake pads for your ebike can be done in one of few ways:
1. Check to see if the make and model of your current brake pad is available. If the current pad is removed, the part number will be marked on the back side of either brake pad. Aventon has used a variety of different brand brake assemblies including Bengal, Zoom, Tektro, and SRAM. Current Aventon bikes will either include Tektro or SRAM brakes depending on the model.
2. If you're unable to locate the exact brake pad make and model, you may also look for an alternatively compatible pad. Looking up your brake assembly model or asking your local shop can direct you to third-party compatible pads for your application.
-Brake Pad Model Numbers
Bengal: PH02 Helix
Zoom: A01S (Shimano)
Tektro: E10.11
SRAM: Avid, Code, DB8 compatible pads
3. There are 3 main brake pad materials: organic, semi-metallic, and metallic. The materials are not universally compatible, so check your components (like the rotor) for a warning stating which type of pads are recommended.
- Organic: Ideal for dryer climates. Organic brake pads make the least amount of noise and feel smoother. These brake pads will not feel as intense when grabbing initially contacting the rotor.
- Metallic: Better suited for harsher riding conditions, such as wet weather or mud. Metallic brake pads are commonly more noisy. however, they will have a stronger initial "bite" when braking, producing the most friction to reduce and control speeds.
- Semi-Metallic: Semi-metallic brake pads are suitable for any riding condition. Regarding noise and performance, they fall right in between the two.
Tools Needed
- Needle Nose Plier
- Hex and Torx compatible tools ranging from 3-5mm
- Hydraulic Brake Piston Press
- Wrench
- Bleed kit
Pad Removal
- Elevate the bike then remove the wheel.
Note: A bicycle repair stand is ideal for this service. - Since there are a plethora of brake pad types, especially if or when you've had any component replacements done, we've listed some of the most common and how to move forward below.
- Retaining Pin: If your brake caliper has a retaining pin that's holding the pads in place, simply remove it. Depending on the design, you may need to slightly bend one of the ends with a plier to release it. Then, slide the pads out from the bottom of the caliper.
- Pin Clip and Bolt: If your brake caliper has a pin clip, remove it before unthreading the retaining pin. Remove the retaining pin and either pull the brake pads up or push them down and out.
- Spring: If there is a spring in your pad system, it will need to be removed along with the pads (new pads will also come with a new spring!).
- Magnetic: If your brake caliper is magnetic, this means that a magnet holds the brake pads against the pistons. If there is a retaining pin and/or clip, remove it and then remove the brake pads.
Prepping the Caliper
The pistons will need to be fully retracted into the caliper. Hydraulic brakes use self-adjusting pistons, meaning as the brake pads wear out, they will slowly move. When you replace the pads, the pistons will have moved closer together, requiring a retraction to make room for the new pads. You will need a Hydraulic Brake Piston Press to retract them. It is recommended to clean the pistons before pressing them back into the caliper to avoid pressing grit into the assembly. Before pressing the pistons into the caliper, open the bleed screw at the lever end, attach the appropriate bleed cup or syringe to allow any excess fluid to be displaced and pressure equalized.
Pad Installation
Installing your new brake pads is essentially the removal process in reverse. Do not be concerned if your correctly and newly installed pads have some wiggle.
- Retaining Pin: Install the brake pads into the brake caliper then insert the retaining pin. If the pin used is a cotter pin, make sure you bend one of the ends with a plier to keep it retained.
- Pin Clip and Bolt: Install the pads into the brake caliper. Insert and thread the retaining pin in and then lastly replace the pin clip.
- Spring: Insert the pads into the spring by orienting the spring in the correct direction. Then hold the pads together with the spring and guide them back into the brake caliper. Do not force them in but instead carefully work them down into place. Some calipers can be a tighter fit compared to others.
- Magnetic: Insert the brake pads, typically inner first and then outer, and the magnet will hold the pads in place against the pistons. Ensure both pads are evenly aligned. If there is a retaining pin and/or clip, reinstall it.
Reinstall the Wheel
Reinstall the wheel and with the two caliper bolts loose, pump the brakes and allow the pistons to re-center the pads to the rotor. Once a firm lever feel is achieved, remove the bleed kit from the lever, close the system, and follow the brake caliper alignment procedure to ensure you achieve quiet and even brake application.
-Bedding Brakes
Below are some examples of uneven brake wear (Figure 6) vs new and even brake wear (Figure 7)
Figure 6 Figure 7
Below is a how-to video: https://www.youtube.com/watch?v=BWQxGzHQZVU&t=2s
-Brake Inefficiency
If your brakes are not stopping you effectively or you are pulling the lever and not getting any braking power, the cause of the issue can be a few different culprits. The first thing to check is if your brake pads are completely worn away. This would be visible by looking into the caliper "window" to see if there is any braking surface left on the pads or removing the pads to check. If they are completely worn, this would normally be paired with a very noisy brake application (scraping sounds) and the pads and rotor should be replaced. If the pads are new or show plenty of pad material left, the issue can either be resolved by adjusting cable tension for mechanical brakes OR a brake bleed for hydraulic brakes.
-Adjusting Cable Tension
If you are pulling the lever nearly or all the way to the handlebar and the brake is not effectively "biting", it is likely you do not have enough cable tension. As mechanical brakes work by pulling a cable, you can increase the effectiveness by simply "shortening" the amount of cable being pulled. This can be accomplished by loosening the pinch bolt on the caliper (shown in Figure 8) and retightening the pinch bolt slightly higher on the cable. This allows the brake to engage sooner and provides a better lever feel. The barrel adjuster on the lever (Figure 9) or caliper (Figure 8) can also be used for more fine adjustments to achieve the same result. If you want to have the brake become more sensitive, you will want to increase the cable tension by turning the barrel adjuster counter-clockwise as if you are unscrewing it or making it longer. If the pads are too close together and rubbing the rotor or if the brake is just too sensitive, you will want to decrease cable tension by turning the barrel adjuster clockwise as if you are screwing it in or making it shorter.
The video below is a brief guide on the adjustments mentioned above:
https://www.youtube.com/watch?v=EHifNC6F0UI
Figure 8 Figure 9
-Brake Bleed
If you have hydraulic brakes and the lever does not seem to perform when pulled or you experience a loss of brake pressure, you may need a brake bleed. Initially is it important to inspect the brake system for any leaks as this would need to be taken care of before any progress can be made. If a leak is spotted, please reach out to Aventon customer support or your local Aventon dealer for assistance on how to resolve this. If there are no leaks but the brake is not working, you will want to bleed the brake. Bleeding the brake is the process of removing trapped air bubbles out of the hydraulic system. Air bubbles can be trapped from assembly or can accumulate as you ride due to factors like component/ fluid heat and brake pad wear pulling air in over time. The reason the air causes an issue is that hydraulic fluid cannot compress but air can compress so it is only taking away from the brake's ability to perform.
To bleed the brake, you will access the bleed port on the lever and the caliper. Using a bleed kit linked HERE, remove the pads and install the proper included spacer. Remove the lever bleed port screw (Figure 10), and attach a syringe fitting to the lever. Then on the caliper, remove the bleed port screw (Figure 10), and with a full syringe, attach it to the caliper bleed port. Push the fresh fluid up through the system. It is important that the angle of the flow is upward (the direction air will accumulate) so that it may be moved out of the system. This means that sometimes you may need to remove a caliper or adjust the lever during this process to remove all of the trapped air. When done properly, you will visibly see air bubbles and/or old, dark fluid leaving the system. You can also tap the caliper with a non-metallic object and flick the brake lines to release more bubbles. Continue until you are no longer seeing any air bubbles leave the system and instead, only fresh fluid. When complete, close the caliper bleed port and remove the syringe from the caliper and then at the lever. Replace the lever bleed port screw and then spray the lever and caliper with 91% alcohol and wipe clean. Replace the pads and wheel, then test that the brake feel has firmed up and that the lever is effective.
Figure 10
The video below will guide you through the bleed process mentioned above:
Tekro
https://www.youtube.com/watch?v=hJfYiDSsjZ8
SRAM