Key Sensors for eBikes: Boosting Functionality and Safety

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For an eBike to achieve maximum performance and safety, whether on the city streets or mountain trails, maintenance of optimal tire pressure is critical. Cutting-edge technologies produced by Merit Sensor empower cyclists to monitor tire pressure in real time, enabling dynamic adjustments to optimize the riding experience.

The Rise of Electric Bicycles

The world experienced a significant “bicycle boom” during the COVID-19 pandemic as the public looked to engage in outdoor exercise and avoid public transportation. To this end, eBikes (bicycles with an electric motor integrated to aid propulsion) emerged as an alternative to traditional manual bicycles, especially in China, the United States, and Germany. 1,2

eBikes have since become more than just an avenue for exercise or a green alternative to transport. Using eBikes allows riders to overcome challenges faced by traditional cyclists, such as incline, distance, and physical exertion, opening cycling to a broader demographic of people, including those with limited fitness and those navigating difficult terrains.3

Tire Pressure

eBike users must ensure optimal tire pressure, which ensures smooth and efficient movement, whereas inadequate pressure can increase resistance, making pedaling more difficult and reducing the distance a user can cycle.

Improper tire pressure also compromises braking and cornering ability, affecting safety and increasing the risk of tire blowouts or punctures.

Standard eBike users may be accustomed to inflating tires to 70 PSI, the standard recommendation, but recommended tire pressures actually vary according to the type of bicycle and tire:

  • Children’s bikes: 20 to 40 PSI
  • Narrow tires (e.g., those used for road bikes) 80 to 130 PSI
  • Medium tires (e.g., hybrid bikes) 50 to 70 PSI
  • Thick tires (e.g., mountain bikes) 30 PSI off-road, 50 PSI on-road

There are other factors that must be considered when determining ideal time pressure, such as riding conditions, rider weight, and personal preference. For example, trail terrain conditions demand pressures from 40 to 70 PSI, while 80 to 130 PSI is optimum for smooth roads.

In addition, for effective distribution of weight, riders should inflate rear tires to two PSI above the front tire, compensating for the extra weight on the rear of most bikes.4,5

Devices for Measuring Pressure

Merit Sensor has manufactured two sensor series to aid eBike users in determining optimum tire pressure: the RS and CMS series.

These devices, compliant with the Restrictions on the Use of Certain Hazardous Substances in Electrical and Electronic Equipment (RoHS), integrate a chemically etched silicon diaphragm with a piezoresistive Wheatstone bridge to provide pressure readings for enhanced safety and performance.

RS Series

Developed in the US, the RS series has been designed to handle a range of pressures from 0 to 500 PSI and represents an uncompensated packaged pressure sensor and transducer.

The RS series is intended for surface-mount devices (SMD) and can be connected to wires or tubes. Its pressure port facilitates a straightforward connection to the tire, ensuring accurate pressure readings for enhanced safety and performance. With its outstanding media compatibility, the RS Series is a versatile and reliable solution for tire pressure monitoring. 6

CMS Series

The CMS Series has an application-specific integrated circuit (ASIC) for calibrating and compensating thermal and non-linearity effects and a compact piezoresistive pressure sensor.

At 6.8 mm by 6.8 mm, it has a wide operational voltage range, exceptional burst pressure, and an energy-efficient mode. This US-manufactured, sensor is ideal for small devices such as tire-pressure monitors and can measure pressures from 2 to 150 PSI. 7

eBike Integration

Merit Sensor technology has been successfully integrated into various tire pressure monitors, as described below.

Real-Time Tire Pressure Sensor

Merit Sensor’s technology can be used inside of a tire pressure sensor device to provide highly accurate pressure data directly to a smart device. The product is easy to install on tube or tubeless tires and allows riders to make informed decisions impacting tire wear, traction, ride comfort, and rolling resistance.8

This application can provide an exceptional accuracy of ± 2 % (total error, 0 – 50 °C) and a resolution of < 0.1 PSI.

Tire Pressure and Temperature Monitor

Dual-function pressure and temperature monitors can be mounted easily onto the tire valve of an eBike and deliver important insights to any smartphone device.

Merit Sensor technology allows for real-time monitoring of pressure, ensuring optimized battery life and rider comfort. Additionally, an early warning system alerts cyclists of slow punctures, reducing the risk of rim damage and maximizing rider safety.

Revolutionizing eBike Riding

The value of efficient and accessible modes of transportation and exercise has been emphasized by the rise of eBikes, which offer a favorable alternative to traditional bicycles. The expanding eBike market has brought with it a need for accurate tire pressure management, which is vital to ensuring rider safety and optimal riding conditions, particularly at fast riding speeds.

The CMS and RS Series of pressure sensors from Merit Sensor typify the recent improvements in cycling technology, catering to the diverse needs of riders. These technologies allow cyclists to enjoy smoother and safer rides with reduced risk of tire and rim damage, improved traction and enhanced comfort, ushering in an exciting new era for electric cycling.

For more information, contact a specialist at Merit Sensor today.

References and Further Reading

  1. Son, J., et al. (2022). Highly reliable triboelectric bicycle tire as self-powered bicycle safety light and pressure sensor. Nano Energy. doi.org/10.1016/j.nanoen.2021.106797
  2. Technavio. [Online] E-Bike Market Analysis APAC, Europe, North America, South America, Middle East and Africa – US, China, Japan, Germany, The Netherlands – Size and Forecast 2024-2028. Available at: https://www.technavio.com/report/e-bike-market-industry-analysis (Accessed on 07 February 2024).
  3. Rérat, P. (2021). The rise of the e-bike: Towards an extension of the practice of cycling? Mobilities. doi.org/10.1080/17450101.2021.1897236
  4. Electric Bike Owner. [Online] eBike Tire Pressure (Best PSI For Every Riding Condition). Available at: https://electricrideowner.com/ebike-tire-pressure/ (Accessed on 07 February 2024).
  5. Spokester. [Online] Bike Tire Pressure – Quick Guide to the right PSI for Bike Tires. Available at: https://spokester.com/blogs/news/bike-tire-pressure-quick-guide-to-the-right-psi-for-bike-tires (Accessed on 11 March 2024).
  6. Merit Sensor. Data Sheet: RS Series. Available at: https://meritsensor.com/assets/documents/pdf/RS-series.pdf
  7. Merit Sensor. Data Sheet: CMS Series. Available at: https://meritsensor.com/assets/documents/pdf/CMS-Series.pdf
  8. Backcountry. [Online] Quarq TyreWiz Air Pressure Sensor – Pair. Available at: https://www.backcountry.com/quarq-tyrewiz-air-pressure-sensor (Accessed on 07 February 2024).

This article is also published on  AZo Sensors.com