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EPA Proposed Emissions Controls (Highway Motorcycle Section)Full Report (aka. the long-ass version (yeah it's longer than this)) IV. Highway Motorcycles In addition to the nonroad vehicles and engines noted above, today's ANPRM also reviews EPA requirements for highway motorcycles. The emissions standards for highway motorcycles were established twenty-three years ago. California recently adopted new emissions standards for highway motorcycles and new standards have also been proposed internationally. There may be opportunities to reduced emissions in a way that also allows manufacturers to benefit from harmonized requirements, which may reduce product lines and production costs. In addition, we believe it is important to consider the emissions standards for highway motorcycles in the context of setting standards for off-highway motorcycles. We are interested in providing regulatory programs for off-highway and highway motorcycles that are consistent, which may also allow for the transfer of technology across product lines for manufacturers. Consequently, we request comment on the appropriateness of examining and potentially revising the highway motorcycle emission standards in the same time frame, and in the same rulemaking, in which we plan to address emission standards for recreational vehicles. A. What Is a Highway Motorcycle, and Who Makes Them? Motorcycles come in a variety of two-and three-wheeled configurations and styles. For the most part, however, they are two- wheeled self-powered vehicles. Federal regulations currently define a motorcycle as ``any motor vehicle with a headlight, taillight, and stoplight and having: two wheels, or three wheels and a curb mass less than or equal to 680 kilograms (1499 pounds).'' (See 40 CFR 86.402- 86.478). Vehicles that otherwise meet the motorcycle definition but have engine displacements less than 50 cubic centimeters (cc) (generally, youth motorcycles, most mopeds, and some motor scooters) are currently not covered by federal regulations. Also currently excluded are motorcycles which, ``with an 80 kg (176 lb) driver, * * * cannot: (1) Start from a dead stop using only the engine; or (2) Exceed a maximum speed of 40 km/h (25 mph) on level paved surfaces' (e.g., some mopeds). Most scooters and mopeds have very small engine displacements and are typically used as short-distance commuting vehicles. Motorcycles with larger engine displacement are more typically used for recreation (racing or touring) and may travel long distances. Both EPA and California regulations further sub-divide highway motorcycles into classes based on engine displacement. Table IV-1 shows how these classes are defined. The currently regulated highway category includes motorcycles termed ``dual-use'' or ``dual-sport,'' meaning that their designs incorporate features that enable them to be reasonably competent on and off road. Dual-sport motorcycles generally can be described as street- legal dirt bikes, since they tend to bear a closer resemblance in terms of design features and engines to true off-highway motorcycles than to highway cruisers or sport bikes. However, another category of motorcycle, referred to as ``enduros,'' are very similar in appearance to dual-sport motorcycles, but are typically equipped with higher performance engines and have traditionally been categorized as nonroad motorcycles and not been subject to the highway emission standards. Therefore, we request comment as to how we can better determine which motorcycles are street-legal and which are not. Throughout this ANPRM the term ``highway motorcycle'' is intended to include all motorcycles covered by the current federal regulations; thus, dual-sport motorcycles are included in this definition. We currently believe that all highway motorcycle engines sold in the U.S., including those that power dual-sport motorcycles, are four-stroke engines. Table IV-1.--Motorcycle Classes ------------------------------------------------------------------------ Motorcycle class Engine displacement (cubic centimeters) ------------------------------------------------------------------------ Class I................................ 50--169. Class II............................... 170--279. Class III.............................. 280 and greater. ------------------------------------------------------------------------ Highway motorcycles are dominated by larger engines, with engine displacements exceeding 1000 cc for the most powerful ``superbikes.'' According to the Motorcycle Industry Council (MIC), in 1998 there were about 5.4 million highway motorcycles in use in the United States (only 565,000 of these were dual-sport), more than three-fourths of which had an engine displacement of over 449 cc.\``1999 Motorcycle Statistical Annual,'' Motorcycle Industry Council.\ Sixty percent had an engine displacement greater than 749 cc. Inclusion of the dual-sport motorcycles in this figure tends to skew the numbers somewhat, even despite the fact that their total numbers are relatively small, because their dirt bike heritage leads them to be weighted towards smaller engines. According to the MIC data, three-fourths of dual-sport motorcycles had an engine displacement of less than 350 cc, whereas two-thirds of the remaining motorcycles (those purely designed for road use) had a displacement of over 749 cc. Total sales in 1998 of highway motorcycles was estimated to be about 411,000, or about 72 percent of motorcycle sales. About 13,000 of these were dual-sport motorcycles. The remaining 28 percent of sales were strictly off-highway motorcycles, which are currently unregulated. We are aware of a half-dozen companies, Honda, Harley Davidson, Yamaha, Kawasaki, Suzuki, and BMW, which account for near 95 percent of all motorcycles sold. Dozens of other minor players make up the remaining few percent. Based on available information, over half of all motorcycles sold in 1998 were made by Honda and Harley Davidson, with the two companies maintaining almost equal market shares of about 25 percent each. B. What Is the Regulatory History? 1. Environmental Protection Agency Regulations In 1974 EPA issued an advance notice of proposed rulemaking that discussed the possible implementation of emission controls for highway motorcycles for the first time and requested comment on a number of issues. Taking into account the comments received on the ANPRM, EPA issued an NPRM the following year for the control of exhaust and crankcase emissions from new motorcycles. The proposal addressed standards for HC, CO, and NOX, proposing a set of interim standards for 1978 and 1979 and final standards equivalent to the light-duty vehicle standards in effect at that time. The NPRM was followed by a Final Rule promulgated in 1977 (42 FR 1126, Jan. 5, 1977) which established interim standards effective for the 1978 and 1979 model years and ultimate standards effective starting with the 1980 model year. The interim standards ranged from 5.0 to 14.0 g/km HC depending upon engine displacement, [[Page 76812]] while the CO standard of 17.0 g/km applied to all motorcycles. The 1980 standards, which were more lenient than those that were proposed and which lacked a NOX standard, are essentially those that remain in effect today. While the final standards did not differ based on engine displacement, the useful life over which these standards must be met ranged from 12,000 km (7,456 miles) for Class I motorcycles to 30,000 km (18,641 miles) for Class III motorcycles. These standards were updated in 1989 to include methanol-fueled motorcycles starting with the 1990 model year, then again in 1994 to include natural gas- fueled and liquefied petroleum gas-fueled motorcycles starting with the 1997 model year. Crankcase emissions from motorcycles are also prohibited. There are no current federal standards for evaporative emissions from motorcycles. The current federal standards are shown in Table IV-2. Table IV-2.--Current Federal Exhaust Emission Standards for Motorcycles ------------------------------------------------------------------------ Engine size HC (g/km) CO (g/km) ------------------------------------------------------------------------ All........................................... 5.0 12.0 ------------------------------------------------------------------------ 2. Regulation by the California Air Resources Board Motorcycle emission standards in California were originally identical to the federal standards that applied to the 1978 through 1981 model years. The definitions of motorcycle classes used by California continue to be identical to the federal definitions. However, California has revised their standards several times to bring them to their current levels. In 1982 the standards were modified to reduce the HC standard from 5.0 g/km to 1.0 or 1.4 g/km, depending upon engine displacement. California adopted an evaporative emission standard of 2.0 g/test for 1983 and later model year motorcycles. In 1984 California amended the regulations for 1988 and later model year motorcycles to further lower emission standards and provide additional compliance flexibility to manufacturers. The 1988 and later standards could be met on a corporate-average basis, and the larger (Class III) bikes (280 cc and above) were split into two separate categories: 280 cc to 699 cc and 700 cc and greater. These are the standards being met in California today. Like the federal standards, there are no currently applicable NOX standards for highway motorcycles in California. Under the corporate-averaging scheme, no individual engine family is allowed to exceed a cap of 2.5 g/km. Like the federal program, California also prohibits crankcase emissions. Table IV-3.--Current California Highway Motorcycle Exhaust Emission Standards ------------------------------------------------------------------------ Engine size (cc) HC (g/km) CO (g/km) ------------------------------------------------------------------------ 50-279.......................................... 1.0 12.0 280-699........................................ 1.0 12.0 700 and above............................... 1.4 12.0 ------------------------------------------------------------------------ In 1998 the California Air Resources Board (CARB) proposed new standards for Class III highway motorcycles that would take effect in two phases--a ``Tier 1'' to start with the 2004 model year, followed by a ``Tier 2'' that would take effect starting with the 2008 model year. These standards were finalized with minor modifications on November 22, 1999. Existing California standards for Class I and II motorcycles remained unchanged. As with the current standards, manufacturers will be able to meet the requirements on a corporate-average basis. Perhaps most significantly, this recent CARB action brings some level of NOX control to motorcycles by establishing a combined HC+NOX standard. No changes were made by the CARB action to the CO standard, which remains at 12.0 g/km. In addition, CARB is providing an incentive program to encourage the introduction of motorcycles compliant with the Tier 2 standard prior to the 2008 model year. This incentive program allows the accumulation of credits that manufacturers can use to meet the 2008 standards. Like the federal program, these standards will also apply to dual sport motorcycles. Table IV-4.--Tier 1 and Tier 2 California Class III Highway Motorcycle Exhaust Emission Standards ---------------------------------------------------------------------------------------------------------------- HC+NOX CO(g/km) Model year Engine displacement (g/km) (g/km) ---------------------------------------------------------------------------------------------------------------- 2004 through 2007 (Tier 1)..................... 280 cc and greater..................... 1.4 12.0 2008 and subsequent (Tier 2).................. 280 cc and greater..................... 0.8 12.0 ---------------------------------------------------------------------------------------------------------------- California also adopted a new definition of small volume that would take effect with the 2008 model year. Historically, California had a definition of small volume that applied to the 1984 through 1987 model years (5,000 units per model year), but no definition that has applied since. Thus, for the 1988 through 2007 model years, all manufacturers must meet the standards, regardless of production volume. Small volume manufacturers, defined in CARB's recent action as a manufacturer with combined California sales of Class I, Class II, and Class III motorcycles not greater than 300 units, do not have to meet new standards until the 2008 model year, at which point the Tier 1 standard applies. CARB intends to evaluate whether the Tier 2 standard should be applied to small volume manufacturers in the future.\ CARB, October 23, 1998 ``Proposed Amendments to the California On-Road Motocycles Regulation'' Staff Report: Initial Statement of Reasons.\ 3. European Regulations The European Commission recently proposed a new phase of motorcycle standards, which would start in 2003, and are considering a second in 2006. Whereas the current European standards make a distinction between two-stroke and four-stroke engines, the proposed standards would apply to all motorcycles regardless of engine type, leading to a technology- independent regulatory framework. The 2003 standards would require emissions to be below the values shown in Table IV-5, as measured over the European ECE-40 test cycle. The phase of standards being considered for 2006 are still in a draft form and have not yet been officially proposed, but in addition to taking another step in reducing motorcycle emissions, the 2006 standards are expected to incorporate an improved motorcycle test cycle, as noted in Section IV.D.2 below. Table IV-5.--European Commission Proposed 2003 Motorcycle Exhaust Emission Standards ------------------------------------------------------------------------ HC (g/km) CO (g/km) NOX (g/km) ------------------------------------------------------------------------ 1.2............................................. 5.5 0.3 ------------------------------------------------------------------------ C. Highway Motorcycle Emission Control Technology 1. Federal Standards While highway motorcycles have had to apply some low-level control technologies to meet the current standards, the current federal standards require a technology mix comparable to the pre-catalyst stage for passenger cars. The standards that took effect starting in the 1980 model year precipitated the elimination of highway two-stroke engines and a transition to a fleet composed entirely of four-stroke engines. In general, the standards prompted the use of leaner air-fuel mixtures, electronic ignition systems, improvements in manufacturing tolerances in the carburetor and fuel handling systems, PCV valves to control crankcase emissions, and some engine redesign and modifications (changes to the camshaft, valve and ignition timing, and combustion chamber design). 2. California Standards Despite the greater stringency of the current California standards (i.e., those that apply in the current model year), most manufacturers have been able to comply without the use of catalytic converters, and only a few expensive high-performance motorcycles have used fuel injection systems. The majority of motorcycles have been able to meet these standards by using, in addition to the measures noted above for the federal standards, engine modifications and more advanced calibration strategies, with air injection systems being commonly used in the larger motorcycle models. A few models have been certified with 3-way catalytic converters and fuel injection systems. The Tier 1 and Tier 2 standards taking effect in California in 2004 and 2008, respectively, will require some additional technologies.\California Air Resources Board, ``Final Statement of Reasons for Rulemaking,'' December 10, 1998.\ Many of the control technologies that have been applied successfully to four-stroke engines in passenger cars may have some potential application to four-stroke motorcycle engines. Some, such as fuel injection and catalytic converters, have already been successfully used on some motorcycle engines, as noted above. Other passenger car technologies may arrive on motorcycles soon due to the upcoming California requirements. However, California did not base the Tier 1 standard effective in 2004 on the widespread application of catalytic converters. California has determined the 1.4 g/km HC+NOX standard will be largely feasible by reducing engine-out emissions using mostly engine systems (e.g., fuel injection, pulse air injection, valve overlap changes), rather than relying on catalytic after- treatment. According to California, the Tier 2 standard will be more of a challenge to industry and existing technologies are likely to be modified and optimized for motorcycle application to achieve 0.8 g/km HC+NOX. They claim that such technologies could include computerized fuel injection, high-efficiency closed-loop two- or three- way catalytic converters, precise air-fuel ratio controls, programmed secondary pulse-air injection, low-thermal capacity exhaust pipes, and others which are available today or in the foreseeable near future. California has also suggested that some manufacturers may be able to meet the Tier 2 standards on some models without the use of catalytic converters. D. Standards and Program Approaches We have identified a number of key issues and decision points that may impact any action we may take regarding standards for highway motorcycles. We request detailed comments and data regarding the issue areas described in this section. 1. Exhaust Emission Standards In general we request comment on the technological feasibility, cost, and appropriateness of implementing new more stringent emission standards for highway motorcycles. We also request comment on technologies that might enable reductions in motorcycle emissions, and the potential magnitude of such reductions. We request comment on the appropriate time frame for implementing new emission standards for highway motorcycles. In addition, we request detailed comments on the following specific issue areas. Harmonization with California. In many program areas, including light-duty and heavy-duty vehicles and engines, harmonization with California has frequently been a significant objective, and is often a desirable outcome for industry. When federal and California compliance programs are harmonized, manufacturers are more easily able to produce engine families that comply with both programs, rather than having to consider whether or how to design and market engine families separately for California and the remaining 49 states. In addition, historically any time the California program is significantly more stringent than the federal program there is a possibility that some individual states will elect to enforce the California program (as several states currently do with light-duty vehicles), further complicating compliance, marketing, and distribution for the manufacturers. Given that California has recently put in place technologically challenging standards for Class III motorcycles in a time frame that we would be likely to consider for a possible federal program, we are likely to look very closely at the pros and cons of harmonizing the federal program with the recently finalized California standards. We request comment on all aspects of the California program and whether the California standards are appropriate for a nationwide federal program. Commenters should address technological feasibility, cost, corresponding potential emissions reductions, appropriate time frame, structure (e.g., a fleet average approach vs. something else), and potential advanced emission control technologies associated with California-level standards and with any other level of standards a commenter may consider appropriate. As noted earlier, the recent action by California did not address emissions from Class I and Class II motorcycles. We request comment on the need to consider emission reductions from all classes of motorcycles, including Class I and Class II. Harmonization with off-highway motorcycles. Since we will be promulgating emission standards for off-highway motorcycles for the first time, it may make sense to have standards that apply to both, off-highway and on-highway motorcycles. This could be beneficial for manufacturers that produce both types of motorcycles, since they could spread their resources across both programs. In addition, the experience and knowledge used in developing emission compliant highway motorcycles could possibly be transferred to off-highway motorcycle applications. However, we also acknowledge that many off-highway motorcycles use two-stroke engines, where two-stroke engines are no longer used in highway applications and some of the information used in meeting highway standards may not be applicable. Therefore, we request comment on the appropriateness of harmonization of highway and off-highway motorcycle emission standards and the costs and corresponding emissions reductions associated with this approach. 2. Test Cycle The test cycle currently used to for compliance with the motorcycle emission standards, in both the federal and California programs, is the FTP-75. Motorcycles are tested on a specialized motorcycle chassis dynamometer on the traditional FTP, the same cycle used for light-duty vehicles and trucks, although the driving schedule speeds and accelerations are reduced for Class I and II motorcycles. It is now widely acknowledged that the traditional FTP does not adequately represent some high-emission modes that vehicles experience in actual use. When the cycle was first adopted for passenger cars in the early 1970's, the limited capabilities of the chassis dynamometers at that time made it necessary to limit the speeds and acceleration rates of the driving cycle. Thus, the top speed and acceleration rates seen on the FTP are much less than most vehicles--especially motorcycles--can achieve on the road. Consequently, we request comment on whether the existing US06 driving cycle for light-duty vehicles and trucks--or some other more representative driving cycle--may be appropriate for highway motorcycles, and if so, what standards might be appropriate. We request data on how motorcycles are driven in actual use that might support or reject the appropriateness of a high-speed/high-acceleration driving cycle for motorcycles. In addition, there is an effort underway under the auspices of the United Nations/Economic Commission for Europe (UN/ECE) to develop a global harmonized world motorcycle test cycle (WMTC). The objective of this work is to develop a scientifically supported test cycle that accurately represents the in-use driving characteristics of motorcycles. The United States is also a participating member of UN/ ECE. EPA has stated that present levels of environmental protection will not be lowered in order to achieve regulatory harmonization. In its recent proposal, the European Commission has announced its intention to consider a global test cycle for the second phase of its proposed standards, expected to take effect in 2006. We request comment on all issues related to pursuing a globally harmonized test cycle. 3. Evaporative Emission Standards As noted earlier, the existing federal program does not require compliance with a limit on evaporative emissions from motorcycles, while California does. We request comments and supporting information on the appropriateness of harmonization with the California evaporative standards or whether other evaporative emission standards might be an appropriate element of the federal program. We also request comment on the costs and corresponding emissions reductions associated with adopting evaporative emission standards. E. Additional Program Considerations 1. Addressing Currently-Excluded Vehicles In addition, we may consider developing appropriate standards for those types of vehicles now excluded from compliance with emission standards. This would include mopeds and scooters that are under 50 cc or that otherwise can not meet the applicability criteria in the regulations (a mix of two-and four-stroke engines). As noted earlier, some of these vehicles do not meet the regulatory definition of motor vehicle by not being able to exceed 25 mph, thus it may be appropriate to consider such vehicles as nonroad vehicles and may be appropriate to regulate them under the recreational vehicle regulations. We request comment on the appropriateness, technological feasibility, and cost of implementing emission standards for these currently unregulated vehicles. We request comment on approaches to reducing emissions from these types of vehicles, and on the technologies that might be used to reduce emissions, both for two- and four-stroke models. 2. Consumer Modifications A significant issue that emerged in the context of the new California standards is the rate at which consumers make modifications to their motorcycles, often using aftermarket parts, to enhance performance, sound, and/or appearance. The Motorcycle Industry Council expressed a concern to California that standards which result in the widespread use of catalysts will achieve less benefits than projected due to consumer tampering with the exhaust systems. Such tampering, which can frequently involve the replacement of exhaust pipes that may include the removal of the catalytic converter, can clearly offset a significant portion of the emission benefits. We request comment on this issue, and in particular request any data that may demonstrate the magnitude of these consumer practices. We request comment on approaches to standard-setting that may mitigate this problem while also enabling motorcycles to take advantage of proven technologies such as catalytic converters. 3. Small Volume Manufacturers The issue of how to define a small volume manufacturer by regulation was also a significant one that arose in the context of the new California standards. Motorcycle manufacturers with fewer than 500 employees meet the current definition of a small business under the classifications established by the Small Business Administration. The current federal regulations define a small volume motorcycle manufacturer as one whose projected U.S. sales of motorcycles is less than 10,000 units. We request comment on how the existing federal definition may interact with the new California definition, and whether, in the context of the new California definition (described earlier), any inequities are created between the two motorcycle compliance programs. We request comment on the appropriateness of the existing federal definition, and, in the context of revised federal standards, what types of compliance flexibilities might be appropriate for those manufacturers defined as small volume. 4. Useful Life As noted earlier, the current federal standards were put in place more than twenty years ago. An important aspect of the overall emission standards, in addition to the numerical limits, is the vehicle useful life over which applicability with the standards must be demonstrated when the vehicle is certified. The current useful life definitions, like the numerical emission limits, were put in place twenty years ago. In conjunction with evaluating the possibility of revising emission standards for highway motorcycles, we believe it may be appropriate to reevaluate the useful life definitions in the context of current technology and driving habits. As is clearly the case with passenger cars, motorcycles may have evolved in the last twenty years to last longer and be driven more miles. Congress found it necessary to increase the useful life of passenger cars in the 1990 Clean Air Act Amendments from 50,000 miles to 100,000 miles based on the longevity of newer passenger cars. It may be time for a similar adjustment for highway motorcycles as design and manufacturing improvements may have extended the typical operating life of highway motorcycles. We request comments and supporting data that may support or refute the need to evaluate and possibly extend the useful life of highway motorcycles. The current useful life definitions are shown in Table IV-6. Table IV-6.--Useful Life Definitions for Motorcycle Classes ------------------------------------------------------------------------ Motorcycle class Useful life ------------------------------------------------------------------------ Class I................................... 5 years or 12,000 km (7,456 miles). Class II.................................. 5 years or 18,000 km (11,185 miles). Class
III................................. 5 years or 30,000 km (18,641 miles).
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