[Code of Federal Regulations]
[Title 40, Volume 30]
[Revised as of July 1, 2004]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR1051.115]

[Page 605-606]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 1051_CONTROL OF EMISSIONS FROM RECREATIONAL ENGINES AND VEHICLES
--Table of Contents
 
          Subpart B_Emission Standards and Related Requirements
 
Sec. 1051.115  What other requirements must my vehicles meet?

    Your vehicles must meet the following requirements:
    (a) Closed crankcase. Design and produce your vehicles so they 
release no crankcase emissions into the atmosphere throughout their 
useful life.
    (b) Emission sampling capability. Produce all your vehicles to allow 
sampling of exhaust emissions in the field without damaging the vehicle. 
Show in your application for certification how this can be done in a way 
that prevents diluting the exhaust sample with ambient air. To do this, 
you might simply allow for extending the exhaust pipe by 20 cm; you 
might also install sample ports in the exhaust (downstream of any 
aftertreatment devices).
    (c) Adjustable parameters. If your vehicles have adjustable 
parameters, they must meet all the requirements of this part for any 
adjustment in the physically adjustable range. Note that parameters that 
control the air-fuel ratio may be treated separately under paragraph (d) 
of this section.
    (1) We do not consider an operating parameter adjustable if you 
permanently seal it or if ordinary tools cannot readily access it.
    (2) We may require you to adjust the engine to any specification 
within the adjustable range during certification testing, production-
line testing, selective enforcement auditing, or in-use testing.
    (d) Other adjustments. This provision applies if an experienced 
mechanic can change your engine's air-fuel ratio in less than one hour 
with a few parts whose total cost is under $50 (in 2001 dollars). 
Examples include carburetor jets and needles. In the case of carburetor 
jets and needles, your vehicle must meet all the requirements of this 
part for any air-fuel ratio within the adjustable range described in 
paragraph (d)(1) of this section.
    (1) In your application for certification, specify the adjustable 
range of air-fuel ratios you expect to occur in use. You may specify it 
in terms of engine parts (such as the carburetor jet size and needle 
configuration as a function of atmospheric conditions).
    (2) This adjustable range (specified in paragraph (d)(1) of this 
section) must include all air-fuel ratios between the lean limit and the 
rich limit, unless you can show that some air-fuel ratios will not occur 
in use.
    (i) The lean limit is the air-fuel ratio that produces the highest 
engine power output (averaged over the test cycle).
    (ii) The rich limit is the richest of the following air-fuel ratios:
    (A) The air-fuel ratio that would result from operating the vehicle 
as you produce it at the specified test conditions. This paragraph 
(d)(2)(ii)(A) does not apply if you produce the vehicle with an unjetted 
carburetor so that the vehicle must be jetted by the dealer or operator.

[[Page 606]]

    (B) The air-fuel ratio of the engine when you do durability testing.
    (C) The richest air-fuel ratio that you recommend to your customers 
for the applicable ambient conditions.
    (3) If the air-fuel ratio of your vehicle is adjusted primarily by 
changing the carburetor jet size and/or needle configuration, you may 
submit your recommended jetting chart instead of the range of air-fuel 
ratios required by paragraph (d)(1) of this section if the following 
criteria are met:
    (i) Good engineering judgment indicates that vehicle operators would 
not have an incentive to operate the vehicle with richer air-fuel ratios 
than recommended.
    (ii) The chart is based on use of a fuel that is equivalent to the 
specified test fuel(s). As an alternative you may submit a chart based 
on a representative in-use fuel if you also provide instructions for 
converting the chart to be applicable to the test fuel(s).
    (iii) The chart is specified in units that are adequate to make it 
practical for an operator to keep the vehicle properly jetted during 
typical use. For example, charts that specify jet sizes based on 
increments of temperature smaller than 20 [deg]F (11.1 [deg]C) or 
increments of altitude less than 2000 feet would not meet this criteria. 
Temperature ranges must overlap by at least 5 [deg]F (2.8 [deg]C).
    (iv) You follow the jetting chart for durability testing.
    (v) You do not produce your vehicles with jetting richer than the 
jetting chart recommendation for the intended vehicle use.
    (4) We may require you to adjust the engine to any specification 
within the adjustable range during certification testing, production-
line testing, selective enforcement auditing, or in-use testing. If we 
allow you to submit your recommended jetting chart instead of the range 
of air-fuel ratios required by paragraph (d)(1) of this section, adjust 
the engine to the richest specification within the jetting chart for the 
test conditions, unless we specify a leaner setting. We may not specify 
a setting leaner than that described in paragraph (d)(2)(i) of this 
section.
    (e) Prohibited controls. You may not design your engines with 
emission-control devices, systems, or elements of design that cause or 
contribute to an unreasonable risk to public health, welfare, or safety 
while operating. For example, this would apply if the engine emits a 
noxious or toxic substance it would otherwise not emit that contributes 
to such an unreasonable risk.
    (f) Defeat devices. You may not equip your vehicles with a defeat 
device. A defeat device is an auxiliary emission-control device or other 
control feature that reduces the effectiveness of emission controls 
under conditions you may reasonably expect the vehicle to encounter 
during normal operation and use. This does not apply to auxiliary 
emission-control devices you identify in your certification application 
if any of the following is true:
    (1) The conditions of concern were substantially included in your 
prescribed duty cycles.
    (2) You show your design is necessary to prevent catastrophic 
vehicle damage or accidents.
    (3) The reduced effectiveness applies only to starting the engine.
    (g) Noise standards. There are no noise standards specified in this 
part 1051. See 40 CFR Chapter I, Subchapter G, to determine if your 
vehicle must meet noise emission standards under another part our 
regulations.