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Federal regulations · Through 2026-08-25 · Newer source version available

40 CFR 86.508-78: -78 Dynamometer.

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Where this section sits in the code
  1. Title 40—Protection of Environment
  2. CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY
  3. SUBCHAPTER C—AIR PROGRAMS
  4. PART 86—CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES
  5. Subpart F—Emission Regulations for 1978 and Later New Motorcycles; Test Procedures

(a) The dynamometer shall have a single roll with a diameter of at least 0.400 metre.

(b) The dynamometer shall be equipped with a roll revolution counter for measuring actual distance traveled.

(c) Flywheels or other means shall be used to stimulate the inertia specified in § 86.529.

(d) A variable speed cooling blower shall direct air to the vehicle. The blower outlet shall be at least 0.40 m 2 (4.31 ft 2) and shall be squarely positioned between 0.3 m (0.98 ft) and 0.45 m (1.48 ft) in front of the vehicle's front wheel. The velocity of the air at the blower outlet shall be within the following limits (as a function of roll speed):

Actual roll speed Allowable cooling air speed

0 km/h to 5 km/h 0 km/h to 10 km/h.

5 km/h to 10 km/h 0 km/h to roll speed + 5 km/h.

10 km/h to 50 km/h Roll speed ±5 km/h.

50 km/h to 70 km/h Roll speed ±10 pct.

Above 70 km/h At least 63 km/h.

(e) The dynamometer shall comply with the tolerances in § 86.529.

Collected 2026-08-27T02:26:04Z. Source file · JSON

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