1 Scope
This document describes the measurement methods of maximum torque and maximum net power of engines for motorcycles and mopeds.
This document is applicable to engines for motorcycles and mopeds (hereinafter referred to as "engines").
2 Normative references
The following documents contain provisions which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB 14622 Limits and measurement methods for emissions from motorcycles (China Stage IV)
GB 18176 Limits and measurement methods for emissions of pollutants from mopeds (China IV)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
net power
power obtained from the crankshaft end of the engine (with the accessories listed in Table 2) on the test bench at rotating speed specified by the manufacturer
Note: If the power can only be measured through the engine's gearbox, the transmission efficiency of the gearbox shall also be taken into account.
3.2
maximum net power
maximum output power of the engine measured at full load
3.3
maximum torque
maximum value of the torque of the engine measured at full load
3.4
series-mounted equipment
equipment designated by the manufacturer for specific purposes
3.5
accessories
components installed on the engine in the torque and net power tests
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Test methods
5 Correction coefficients of power and torque of spark ignition engines
6 Correction coefficients of power and torque of compression ignition engines
7 Permissible measurement error of maximum torque and maximum net power
8 Test method for maximum torque and maximum power of hybrid synergy drive systems
Annex A (Normative) Measurement of maximum torque and maximum net power of engines (by controlling the engine temperature)
1 Scope
This document describes the measurement methods of maximum torque and maximum net power of engines for motorcycles and mopeds.
This document is applicable to engines for motorcycles and mopeds (hereinafter referred to as "engines").
2 Normative references
The following documents contain provisions which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB 14622 Limits and measurement methods for emissions from motorcycles (China Stage IV)
GB 18176 Limits and measurement methods for emissions of pollutants from mopeds (China IV)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
net power
power obtained from the crankshaft end of the engine (with the accessories listed in Table 2) on the test bench at rotating speed specified by the manufacturer
Note: If the power can only be measured through the engine's gearbox, the transmission efficiency of the gearbox shall also be taken into account.
3.2
maximum net power
maximum output power of the engine measured at full load
3.3
maximum torque
maximum value of the torque of the engine measured at full load
3.4
series-mounted equipment
equipment designated by the manufacturer for specific purposes
3.5
accessories
components installed on the engine in the torque and net power tests
Contents of GB/T 20076-2021
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Test methods
5 Correction coefficients of power and torque of spark ignition engines
6 Correction coefficients of power and torque of compression ignition engines
7 Permissible measurement error of maximum torque and maximum net power
8 Test method for maximum torque and maximum power of hybrid synergy drive systems
Annex A (Normative) Measurement of maximum torque and maximum net power of engines (by controlling the engine temperature)
