['Air Programs']
['Mobile Emission Sources']
12/22/2025
Copyright 2026 J. J. Keller & Associate, Inc. For re-use options please contact copyright@jjkeller.com or call 800-558-5011.
...
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.
| Lap | Description | Typical accel rate (MPH/s) |
|---|---|---|
| 1 | (start engine) Idle 10 sec | 0 |
| 1 | Mod accel to 30 MPH | 4 |
| 1 | Cruise at 30 MPH for 1/4 lap | 0 |
| 1 | Mod. decel to 20 MPH | −5 |
| 1 | Mod accel to 30 MPH | 4 |
| 1 | Cruise at 30 MPH for 1/4 lap | 0 |
| 1 | Mod. decel to stop | −5 |
| 1 | Idle 5 sec | 0 |
| 1 | Mod accel to 35 MPH | 4 |
| 1 | Cruise at 35 MPH for 1/4 lap | 0 |
| 1 | Mod. decel to 25 MPH | −5 |
| 1 | Mod accel to 35 MPH | 4 |
| 1 | Cruise at 35 MPH for 1/4 lap | 0 |
| 1 | Mod. decel to stop | −5 |
| 2 | Idle 10 sec | 0 |
| 2 | Mod accel to 40 MPH | 3 |
| 2 | Cruise at 40 MPH for 1/4 lap | 0 |
| 2 | Mod. decel to 30 MPH | −5 |
| 2 | Mod accel to 40 MPH | 3 |
| 2 | Cruise at 40 MPH for 1/4 lap | 0 |
| 2 | Mod. decel to stop | −5 |
| 2 | Idle 5 sec | 0 |
| 2 | Mod accel to 45 MPH | 3 |
| 2 | Cruise at 45 MPH for 1/4 lap | 0 |
| 2 | Mod. decel to 35 MPH | −5 |
| 2 | Mod accel to 45 MPH | 3 |
| 2 | Cruise at 45 MPH for 1/4> lap | 0 |
| 2 | Mod. decel to stop | −5 |
| 3 | Idle 10 sec | 0 |
| 3 | Hard accel to 55 MPH | 4 |
| 3 | Cruise at 55 MPH for 1/4 lap | 0 |
| 3 | Mod. decel to 45 MPH | −5 |
| 3 | Mod accel to 55 MPH | 2 |
| 3 | Cruise at 55 MPH for 1/4 lap | 0 |
| 3 | Mod. decel to 45 MPH | −5 |
| 3 | Mod accel to 60 MPH | 2 |
| 3 | Cruise at 60 MPH for 1/4 lap | 0 |
| 3 | Mod. decel to 50 MPH | −5 |
| 3 | Mod. accel to 60 MPH | 2 |
| 3 | Cruise at 60 MPH for 1/4 lap | 0 |
| 3 | Mod. decel to stop | −4 |
| 4 | Idle 10 sec | 0 |
| 4 | Hard accel to 80 MPH | 3 |
| 4 | Coastdown to 70 MPH | −1 |
| 4 | Cruise at 70 MPH for 1/2 Lap | 0 |
| 4 | Mod. decel to 50 MPH | −3 |
| 4 | Mod accel to 65 MPH | 2 |
| 4 | Cruise at 65 MPH for 1/2 lap | 0 |
| 4 | Mod. decel to 50 MPH | −3 |
| 5 | Mod accel to 75 MPH | 1 |
| 5 | Cruise at 75 MPH for 1/2 lap | 0 |
| 5 | Mod. decel to 50 MPH | −3 |
| 5 | Lt. accel to 70 MPH | 1 |
| 5 | Cruise at 70 MPH for 1/2 lap | 0 |
| 5 | Mod. decel 50 MPH | −3 |
| 6 | Mod accel to 70 MPH | 2 |
| 6 | Coastdown to 60 MPH | −1 |
| 6 | Cruise at 60 MPH for 1/2 lap | 0 |
| 6 | Mod. decel to 50 MPH | −4 |
| 6 | Mod. accel to 65 MPH | 1 |
| 6 | Cruise at 65 MPH for 1/2 lap | 0 |
| 6 | Mod. decel to stop | −4 |
| 7 | Idle 45 sec | 0 |
| 7 | Hard accel to 55 MPH | 4 |
| 7 | Cruise at 55 MPH for 1/4 lap | 0 |
| 7 | Mod. decel to 40 MPH | −5 |
| 7 | Mod. accel to 55 MPH | 2 |
| 7 | Cruise at 55 MPH for 1/4 lap | 0 |
| 7 | Mod. decel to 40 MPH | −5 |
| 7 | Mod. accel to 50 MPH | 2 |
| 7 | Cruise at 50 MPH for 1/4 lap | 0 |
| 7 | Mod. decel to 40 MPH | −5 |
| 7 | Mod. accel to 50 MPH | 2 |
| 7 | Cruise at 50 MPH for 1/4 lap | 0 |
| 7 | Mod. decel to stop | −5 |
The standard road cycle is represented graphically in the following figure:
[71 FR 2837, Jan. 17, 2006]
['Air Programs']
['Mobile Emission Sources']
UPGRADE TO CONTINUE READING