Regulations last checked for updates: Nov 22, 2024

Title 40 - Protection of Environment last revised: Nov 20, 2024
Appendix Appendix V - Appendix V to Part 86—The Standard Road Cycle (SRC)

1. The standard road cycle (SRC) is a mileage accumulation cycle that may be used for any vehicle which is covered by the applicability provisions of § 86.1801. The vehicle may be run on a track or on a mileage accumulation dynamometer.

2. The cycle consists of 7 laps of a 3.7 mile course. The length of the lap may be changed to accommodate the length of the service-accumulation track.

Description of the SRC

Lap Description Typical accel rate
(MPH/s)
1(start engine) Idle 10 sec0
1Mod accel to 30 MPH4
1Cruise at 30 MPH for 1/4 lap0
1Mod. decel to 20 MPH−5
1Mod accel to 30 MPH4
1Cruise at 30 MPH for 1/4 lap0
1Mod. decel to stop−5
1Idle 5 sec0
1Mod accel to 35 MPH4
1Cruise at 35 MPH for 1/4 lap0
1Mod. decel to 25 MPH−5
1Mod accel to 35 MPH4
1Cruise at 35 MPH for 1/4 lap0
1Mod. decel to stop−5
2Idle 10 sec0
2Mod accel to 40 MPH3
2Cruise at 40 MPH for 1/4 lap0
2Mod. decel to 30 MPH−5
2Mod accel to 40 MPH3
2Cruise at 40 MPH for 1/4 lap0
2Mod. decel to stop−5
2Idle 5 sec0
2Mod accel to 45 MPH3
2Cruise at 45 MPH for 1/4 lap0
2Mod. decel to 35 MPH−5
2Mod accel to 45 MPH3
2Cruise at 45 MPH for 1/4> lap0
2Mod. decel to stop−5
3Idle 10 sec0
3Hard accel to 55 MPH4
3Cruise at 55 MPH for 1/4 lap0
3Mod. decel to 45 MPH−5
3Mod accel to 55 MPH2
3Cruise at 55 MPH for 1/4 lap0
3Mod. decel to 45 MPH−5
3Mod accel to 60 MPH2
3Cruise at 60 MPH for 1/4 lap0
3Mod. decel to 50 MPH−5
3Mod. accel to 60 MPH2
3Cruise at 60 MPH for 1/4 lap0
3Mod. decel to stop−4
4Idle 10 sec0
4Hard accel to 80 MPH3
4Coastdown to 70 MPH−1
4Cruise at 70 MPH for 1/2 Lap0
4Mod. decel to 50 MPH−3
4Mod accel to 65 MPH2
4Cruise at 65 MPH for 1/2 lap0
4Mod. decel to 50 MPH−3
5Mod accel to 75 MPH1
5Cruise at 75 MPH for 1/2 lap0
5Mod. decel to 50 MPH−3
5Lt. accel to 70 MPH1
5Cruise at 70 MPH for 1/2 lap0
5Mod. decel 50 MPH−3
6Mod accel to 70 MPH2
6Coastdown to 60 MPH−1
6Cruise at 60 MPH for 1/2 lap0
6Mod. decel to 50 MPH−4
6Mod. accel to 65 MPH1
6Cruise at 65 MPH for 1/2 lap0
6Mod. decel to stop−4
7Idle 45 sec0
7Hard accel to 55 MPH4
7Cruise at 55 MPH for 1/4 lap0
7Mod. decel to 40 MPH−5
7Mod. accel to 55 MPH2
7Cruise at 55 MPH for 1/4 lap0
7Mod. decel to 40 MPH−5
7Mod. accel to 50 MPH2
7Cruise at 50 MPH for 1/4 lap0
7Mod. decel to 40 MPH−5
7Mod. accel to 50 MPH2
7Cruise at 50 MPH for 1/4 lap0
7Mod. decel to stop−5

The standard road cycle is represented graphically in the following figure:

[71 FR 2837, Jan. 17, 2006]