The long road.

In July 1950 the limits became 3.00 m long and 1.30 m wide, with 350 cc for a four-stroke and 200 cc for a two-stroke, and the rules began to tell two-wheelers from three-wheelers and four-wheelers.

In 1951 the engine limits moved to 360 cc and 240 cc, the year the Road Transport Vehicle Law and its safety standards came into force.

That body size, 3.00 m by 1.30 m by 2.00 m, held until 1976.

On 1 April 1955 the same 360 cc ceiling began to apply to two-stroke and four-stroke engines alike, because four-stroke engines had improved enough that the old split was dropped.

The body stayed at 3.00 m by 1.30 m by 2.00 m, and Subaru's own Sambar history lists this standard, 360 cc or less from April 1955, as the one its first Sambar launched under.

In May the Ministry of International Trade and Industry announced its outline for a national car, and in October Suzuki began selling the Suzulight, a small passenger car in the class.

In November 1960 Daihatsu put its first kei four-wheeler on sale, the Hijet, a bonnet truck with a 356 cc two-stroke twin of 17 horsepower.

It followed the Midget, a three-wheeled kei truck of August 1957 that small shops and delivery businesses had bought in numbers.

A feature on Daihatsu's own Hijet history page says the three-wheeler handled only so well and put the driver astride the engine, and that the four-wheeler was made for people who disliked that.

In February 1961 Subaru put the Sambar truck on sale.

It was a cab-over with a rear mounted 360 cc air-cooled two-stroke engine driving the rear wheels, a layout Subaru kept for about forty years.

Subaru's own release says it chose the cab-over for the best loading efficiency in a kei cargo market of bonnet trucks, and its timeline sets the Sambar under the kei standard of 360 cc or less in force since April 1955.

In October 1961 Suzuki put the Suzulight Carry FB on sale.

Suzuki says it was built as a proper kei four-wheeled truck at a time when commercial vehicles were moving from kei three-wheelers to kei four-wheelers.

It was a semi cab-over with a 359 cc air-cooled two-stroke twin of 21 horsepower and a bed of 1.502 square metres, which Suzuki calls the largest in its class.

American frozen chicken had won a growing share of the West German market by the early 1960s, nearly a quarter of its poultry imports by 1962 against about one percent in 1956.

In 1962 the European Economic Community, the six nation Common Market, brought in Regulation 22 of its common farm policy, which Cato says tripled West Germany's duty on poultry from 4.5 cents a pound to about 13.5 cents.

Time reported that France pressed for the higher tariff and won West Germany's support, hoping to win more of that market for its own farmers.

In August 1963 Honda began selling the T360, the first four-wheeled vehicle it sold, and it was a kei truck with a twin cam engine of 30 horsepower that turned up to 8,500 rpm.

Honda says its management chose a truck because most of the demand was for commercial vehicles, and the S500 sports car followed in October.

A Japanese bill to promote chosen industries, which Honda says threatened its entry into cars, was put to the Diet in 1963 and again in 1964 and never passed.

Talks between Washington and Brussels failed to settle the matter.

On 28 October 1963 the GATT Council set up a panel of experts, at the request of both sides, to measure the harm from Germany's higher poultry tariff, and on 21 November the panel put it at $26 million of American trade.

That was below the American estimate of $40 million and above the European Community's $16 million, and the United States took the figure as the amount of European trade it could tax in return.

On 17 December 1963 Congress rewrote the 1955 air pollution research law as the Clean Air Act, a program of federal grants and leadership with the states and cities responsible for control at the source.

Its findings name the growing use of motor vehicles among the causes of rising pollution, and a section on automotive vehicle and fuel pollution told the Secretary of Health, Education and Welfare to encourage industry work on exhaust devices and to report to Congress every six months.

It set no limit on what a car could emit.

On 20 October 1965 Public Law 89-272 added a title to the Clean Air Act, the Motor Vehicle Air Pollution Control Act.

It told the Secretary of Health, Education and Welfare to set emission standards for new motor vehicles and engines as soon as practicable, with regard to technology and cost.

It also barred the sale or importation of a new vehicle that did not meet them.

A new vehicle offered for import in breach was to be refused admission, or admitted under bond on terms that would bring it into conformity.

On 30 March 1966 the Department of Health, Education and Welfare published Part 85 of its rules, which set crankcase and exhaust limits for new gasoline vehicles from the 1968 model year.

An engine of more than 140 cubic inches was held to 275 parts per million of hydrocarbons and 1.5 percent carbon monoxide, with looser limits for smaller engines.

As first published the exhaust rule left out motorcycles, commercial vehicles of more than half a ton and any vehicle with an engine under 50 cubic inches, which is about 820 cc and so more than twice the size of a 360 cc kei engine.

In August 1966 Mitsubishi began selling the Minicab truck, a cab-over with an air-cooled 359 cc two-stroke twin of 21 horsepower.

Mitsubishi's own history says trucks of every size were moving to the cab-over form and that its kei commercial vehicles followed.

Its earlier kei commercial vehicle, the bonnet type Mitsubishi 360, had gone on sale in April 1961.

On 9 September 1966 Public Law 89-563, the National Traffic and Motor Vehicle Safety Act, told the Secretary of Commerce to set Federal motor vehicle safety standards stated in objective terms.

A vehicle made after a standard took effect could not be sold or imported unless it conformed, and an importer who sold the vehicle on counted as a manufacturer under the Act.

A non-conforming vehicle offered for import was to be refused admission or let in on a bond that it would be brought into conformity, and the Act set up a National Traffic Safety Agency, which became the National Highway Traffic Safety Administration.

The first nineteen standards were issued on 31 January 1967, published in the Federal Register on 3 February and effective on 1 January 1968, with the seat belt assembly standard a year earlier on 1 March 1967.

They applied to new motorcycles and to new vehicles over 1,000 pounds of curb weight, from whatever country they came.

From that date a vehicle built abroad to another country's rules had to meet them to be imported, and a vehicle that did not was refused entry.

The Environmental Protection Agency was created on 2 December 1970, and on 31 December Public Law 91-604, the Clean Air Amendments of 1970, gave its Administrator the job of setting emission standards for new vehicles and wrote the target into law.

Light vehicles of the 1975 model year had to emit at least 90 percent less carbon monoxide and hydrocarbons than the 1970 standards allowed, and those of 1976 at least 90 percent less oxides of nitrogen than 1971 vehicles averaged.

The Act also made it unlawful for any person, and not only a manufacturer, to import a new vehicle without an EPA certificate of conformity, unless the Administrator's rules said otherwise.

The 1966 Safety Act and the Clean Air Act let an importer bring in a car not built to US rules if it was modified to meet them and a bond was posted until it was.

EPA and Customs wrote joint rules for this in 1972, and NHTSA and Customs added theirs in 1978.

A foreign carmaker told GAO the aim had been to spare returning servicemembers and diplomats from selling a car bought abroad, and GAO found no sign that Congress meant to limit it to them.

On 1 January 1976 the limit rose from 360 cc to 550 cc, the length to 3.20 m and the width to 1.40 m, with height held at 2.00 m.

The ministry says stricter exhaust and noise rules had taken power out of small engines, so displacement was raised to win it back.

The ministry also says the body grew with the larger engine, while the association gives the larger body as a safety measure.

In July 1977 Honda's TN-Acty replaced the TN-V as its kei truck, and the Acty name that Honda still uses began.

Honda's archive lists the line below, and by then the kei class had been 550 cc for a year and a half.

Mercedes-Benz told GAO that no modifier could properly convert its European models, and BMW and Ford and Jaguar and Volvo said it could be done only at a prohibitive cost.

Dealers said they carried design, service and warranty duties that gray market importers did not, and a dealer survey reported in the press found that only 5 percent of the cars brought to them met emission rules and 1 percent met every safety standard.

A press account says Mercedes-Benz of North America and a dealers' association backed a 1985 bill to bar such imports.

An importers' association told a House subcommittee on 30 April 1985 that NHTSA had received no safety complaints about these cars and that most safety changes were straightforward.

It also said every car had to be tested for emissions while a carmaker's imports needed only a prototype tested.

NHTSA counted about 400 firms in the trade, the association said it employed about 10,000 people, and the Department of Transportation objected to an outright ban.

GAO sampled 50 cars imported in 1984 and found papers late for 21 and none of 5 examined in depth fully compliant.

EPA could not find emissions papers for 26 of the 50 and had granted age exemptions in 12 of the other 24, and a 1984 EPA and California check found that 1 of 27 approved cars passed every part of the test.

Bills to tighten the program passed both houses in the 99th Congress without final action, and imports had fallen to about 23,900 in 1986.

EPA's rule of 25 September 1987 let only independent commercial importers bring in cars not built to US emission rules and ended a 1981 policy that had let a person import one car five model years old or older.

The age exemption that still stands in 40 CFR 85.1511(f)(2) covers vehicles 'greater than twenty OP years old', the year of import less the year of production.

EPA's 2010 CFR traces that section to this rule, but the rule's own text was not read, so when the twenty year line first appeared and why is not confirmed.

On 31 May 1988 the Court decided K mart Corp. v.

Cartier, Inc., 486 U.S. 281, about trademarked goods bought abroad and sold here without the US owner's consent.

It upheld Customs' rule that lets in goods made by the trademark owner or an affiliate under common control and struck down its rule for goods made by an independent maker the owner had authorized, each by 5 to 4.

It was a trademark case and not a car safety case.

New section 108(i) of the Safety Act, added by Public Law 100-562, said the import bar and the refusal of entry 'shall not apply to any motor vehicle that is 25 or more years old'.

So the exemption dates from 1988 and not from a later amendment, as some commercial pages say.

The statute gives no reason for 25, and a commercial page quotes a bill summary calling such cars classic or antique that was not read at its source.

On 1 January 1990 the limit rose to 660 cc and the length to 3.30 m, with the width kept at 1.40 m.

The ministry says the extra length was for absorbing a front collision, and both it and the association say the extra displacement was to keep performance as safety and pollution equipment added weight.

Daihatsu's own history prints the 660 cc Hijet for March 1990 and Subaru's release dates the 660 cc Sambar to the same month.

NHTSA's records show permanent gray market imports at more than 65,000 in 1985 and under 300 in 1992.

The grandfather clause that let some cars be converted by firms other than registered importers ended on 31 October 1992.

NHTSA and industry officials told GAO the main cause was the exchange rate, with the dollar at more than 3 marks in 1985 and 1.7 in August 1993.

Public Law 103-272 of 5 July 1994 restated the transportation laws in Title 49, and the old section 108(i) became 49 U.S.C. 30112(b)(9), 'a motor vehicle that is at least 25 years old'.

The words changed from '25 or more years old' to 'at least 25 years old', and the code's table of sources lists 15 U.S.C. 1397(i).

NHTSA counts the 25 years from the date of manufacture, and its rule at 49 CFR 591.5(i)(1) says '25 or more years old'.

On 1 October 1998 the class took the size it has now, 3.40 m long and 1.48 m wide, with 660 cc and 2.00 m unchanged.

Kei crash standards were brought level with those of regular and small cars, with a faster front crash test and a new side impact test, so the body grew 10 cm in length and 8 cm in width to carry the structure.

The class still costs its owner less than a small car, as the ministry's 2013 table and the association's 2025 table show.

Kansas defined a micro utility truck in a 2008 law and Oklahoma wrote a mini truck class that took effect on 1 November 2008.

Minnesota followed with a law signed on 21 May 2009 that defines a mini truck as a four wheeled vehicle of 660 cc or less not built to federal safety standards and lets a county or city permit it on chosen roads, and Arkansas wrote its class in 2009 as well.

Nebraska and Louisiana passed theirs in 2010, Kentucky's 2013 act names a 'lightweight Japanese kei class utility vehicle', and Indiana in 2015 and Tennessee in 2016 added their own.

EPA's rule of 8 October 2008, effective 8 December 2008, required a certificate for the engine of a motor vehicle converted to nonroad use before it reached Customs.

EPA's February 2009 guidance says the Japanese kei class trucks limited to 25 mph were the most popular vehicles affected, and its own examples include uncertified trucks converted in 2003 and 2007.

A dealer told NPR in 2025 that the first buyers were large factories and universities and zoos, with enthusiasts coming later, and no source read dates those first arrivals.

EPA-420-F-09-014 of February 2009 says that only a mini truck permanently modified so its speed is 25 mph or less is a nonroad vehicle and every other mini truck is a motor vehicle.

A governed truck needs a certified engine before it reaches Customs, an importer may certify as a small volume manufacturer and an independent commercial importer cannot certify nonroad engines.

Removing the governor from a certified truck is tampering under the Clean Air Act.

EPA data show mini truck engine families from model year 2010, the first model year after certification became required for imported mini trucks.

Seventeen distinct three and four cylinder families were certified from 2010 to 2026, nine of them for model year 2026, with maximum engine power from 14.46 to 29.9 kW against stock ratings of 34 to 47 kW for the same engines.

The lane serves newer trucks governed to 25 mph, and a kei truck built after the 25 year line and before model year 2010 has no federal door until it turns 25.

EPA's heavy duty rule at 88 FR 4296, published 24 January 2023 and effective 27 March 2023, removed the exemption in 40 CFR 1068.315(i) for nonroad engines first made at least 21 years earlier.

EPA said it was no longer appropriate now that part 1068 covers many long lived machines, and that importers could misuse it to bring in high emitting engines.

The twin rule for road vehicles, 40 CFR 85.1511(f)(2), was left alone.

Since a 2021 law Maine treats any motor vehicle not built to federal safety and emission standards as an off road vehicle that cannot be registered, and the state's BMV table names mini trucks.

LD 63, to clarify that certain imported vehicles are not off road, ended on 28 February 2024 when the committee's ought not to pass report was accepted.

LD 875, to allow mini trucks on roads, ended in leave to withdraw on 21 March 2024.

The 1963 truck duty never came off, and the Commerce Department wrote in 2021 that the United States has taxed light trucks at 25 percent since 1964 under Proclamation 3564.

Customs and Border Protection ruled in June 2024 that a 1993 Subaru Sambar falls in tariff line 8704.31.01 at 25 percent, and in February 2026 it ruled the same for a 1990 Honda Acty.

Age does not change the rate, because the 25 year rule decides whether a truck may enter and not what it pays.

The Massachusetts Registry of Motor Vehicles announced on 17 September 2024 that kei vehicles could be registered from 18 September, after a halt earlier in 2024 that the press reported, and it said it was still reviewing safety.

In Michigan the press reported in October 2024 that the state had cancelled some owners' road titles and then began sending reinstatement letters after a lawsuit, and the Department of State's titles FAQ now says kei class vehicles 25 years and older can be titled for the road.

Both are agency policy and not a new statute.

In December 2024 the press reported a proposed Colorado DMV rule that would have held that Japanese kei vehicles and mini trucks are not motor vehicles under state law and so would not be titled or registered for road or off road use, with no exception for vehicles 25 years or older.

By 19 December the press reported a DMV email saying the agency had decided to cancel the rulemaking, to be published in the Colorado Register on 25 December.

A DMV spokeswoman had said the rule aimed to clarify how state law classifies vehicles.

Georgia's Department of Revenue applies a bar on unconventional motor vehicles, O.C.G.A. 40-3-30.1(f), to refuse title and registration to kei trucks at any age, in its bulletin MVD-2023-05.

House Bill 1239 in 2024 and House Bill 308 in 2025 would each have let such vehicles be registered, and HB 308 passed both chambers and was vetoed on 14 May 2025 over a separate provision on speed assistance devices.

House Bill 957 in 2026 passed the House on 9 February and was tabled in the Senate on 31 March by bill tracker accounts, so a new bill would be needed in 2027.

Senate Bill 1816 passed the Senate on 2 April 2025 and the House on 21 May 2025, and the governor signed it on 20 June 2025 with effect that day.

It lets a miniature vehicle that complies with applicable federal law be titled and registered as a motor vehicle and driven on any public highway where it can obey the traffic laws.

The Senate research analysis says the state DMV had reversed a ban on registering them in April 2024, and the enrolled act carries no 25 year clause.

Arizona's rule R17-4-206, amended effective 1 February 2026, exempts a foreign made vehicle 25 years or more from its manufacture date from the federal conformity certificate and still asks for an MVD inspection and an emissions test.

Vermont's Act 153 was signed on 16 June 2026 and took effect on 1 July 2026, defining a kei vehicle and registering it as a pleasure car or a farm truck with no kei speed limit.

Alaska's SB 239 was signed on 24 June 2026 with no vote against it and lets the DMV title and register a legally imported vehicle at least 25 years old as an ordinary motor vehicle.

By the engine file the Suzuki Carry DA62T and the Mazda Scrum DG62T reach 25 from September 2026 with their last units in April 2027, and the Every DA62V and Scrum DG62V vans turn 25 from the same month.

The Carry DA63T and Scrum DG63T follow from May 2027, with their last units turning 25 in August 2038.

Each truck's own date of manufacture decides to the day, and only DA62T trucks built from 4 September to 28 October 2001 are 25 on 28 October 2026.

By the engine file the Daihatsu Hijet cargo S320V turns 25 from December 2029, the Suzuki Every DA64V from August 2030, the Mazda Scrum van DG64V from September 2030 and the Carry DA65T from November 2030.

The Hijet truck S201P and cargo S321V, the generation with the KF-VE engine, turn 25 from December 2032.

Until a chassis reaches that line the file classes it as newer and nonroad only.