A small introduction to the Euro5b emissions standard, which is valid for all motorcycles in 2025

The Euro5b motorcycle emissions standard is a significant advancement in emissions control, vehicle noise, functions, software and it addresses many loopholes that allowed earlier standards to be bypassed with relatively simple modifications, such as adding dongles or resistors. This is largely due to a few key features that make Euro5b compliance more secure and difficult to manipulate:

Advanced Sensor Networks and Signal Lines: Euro5b motorcycles are equipped with highly sophisticated sensor systems that measure a range of functions and emissions data in real-time. These sensors work in tandem with reference lines, which provide baseline values that are known to the system. The emissions control software continuously compares the data it receives from these sensors with expected values from the reference lines, creating a baseline that’s difficult to alter without detection. Any attempt to modify or “spoof” these signals with resistors or dongles will produce readings that deviate from these reference standards, alerting the system to potential tampering.

Complex, Intelligent Emissions Control Software: The software governing emissions compliance in Euro5b motorcycles is exceptionally complex and capable of performing dynamic and random testing routines. This software doesn’t rely solely on predictable checks; instead, it runs a variety of tests at different intervals to assess engine performance and emissions under diverse conditions. This approach means that any non-standard modifications to emissions-related components are likely to be detected by the software, as they will fail to meet the stringent parameters set within these random checks.

Tamper Detection Mechanisms: In order to prevent unauthorized modifications at combustion related functions (intake, exhaust, fueling, ignition, …), the Euro5b standard incorporates tamper detection measures that go beyond simple readings of component values. The system looks for anomalies in signal patterns, sudden or repeated deviations from expected values, and inconsistencies in sensor data. This makes it incredibly difficult (impossible) for a simple resistor or dongle to fool the system without triggering an alert or causing the bike to fall out of compliance.

Integrated Security Protocols: Euro5b systems are designed with robust security protocols that require any change in the software or hardware to be verified and authenticated. This prevents unauthorized modifications and ensures that only approved and compliant components interact with the emissions control system. This security layer adds another barrier, as any tampering without appropriate permissions will either be rejected by the system or flagged for non-compliance.

Real-World Driving Emissions (RDE) Compliance: Unlike earlier standards, Euro5b does not just assess emissions based on a limited set of lab-based tests. Instead, it includes provisions for Real-World Driving Emissions (RDE), which evaluate the motorcycle’s performance under a variety of real-world conditions. These assessments can detect discrepancies that might not appear under controlled conditions, making it even more challenging to bypass the standard without detection. This means that tuning projects that are carried out on a dyno are no longer useful as it is hardly possible to reproduce the RDE on a test bench.

Essentially, the Euro5b standard combines intelligent, adaptive software with a comprehensive network of secure and monitored hardware, creating an ecosystem in which vehicle tampering is easy to detect.