Federal, state and local agents yesterday arrested more than 80 members of the Bandidos motorcycle gang in eight states on narcotics, firearms and racketeering charges, the FBI announced.

The raids were described as a major crackdown on the illegal manufacture and distribution of methamphetamines, stimulants also called "speed" and "crank."

The operation was the largest combined effort mounted against such a gang, FBI Director William H. Webster said in an announcement. Federal law enforcement authorities have described motorcycle gangs as a new form of organized crime and say they are responsible for the major portion of manufactured drugs such as speed and PCP, known as "angel dust," distributed in the country.

The Bandido Motorcycle Club is one of the "big four" motorcycle gangs in the country, along with the Hell's Angels, the Outlaws and the Pagans, the FBI said. The Bandidos are believed to have about 300 members in 10 states, with a chapter in Australia.

The slang name "crank" for a methamphetamine reportedly comes from the gangs' practice of storing the contraband in the crank cases of their motorcycles.

Most of yesterday's arrests were in Arkansas, Louisiana and Texas, where the gang's membership is concentrated, according to FBI spokesman Lane Bonner. Arrests also were reported in Washington state, Colorado, Missouri, South Carolina and South Dakota.

Coordinated by the Justice Department's organized crime and drug enforcement task force, the raids involved agents of the FBI, the Drug Enforcement Administration, the federal Bureau of Alcohol, Tobacco and Firearms, and hundreds of state and local police, armed with 90 warrants.

The arrests were carried out without serious violence, Bonner reported, although "we had to break in a few doors."

Twenty-seven arrest warrants were issued in Arkansas, with 14 of the arrests made in the first hour of the raids, according to Ray McElhaney, special agent in charge of the FBI office in Little Rock.

More than a dozen people were arrested in Whatcom County and Puyallup, Wash., federal officials in Seattle said.

In the Houston-Corpus Christi area, where the club reportedly has its "mother chapter," officials reported 12 arrests.

Federal agencies intensified their investigations of major outlaw motorcycle gangs in 1981, as their numbers ballooned and they took on an international aspect, Webster said. Some were believed to have established a relationship with more traditional organized crime families, he said.

Last July, 22 members and associates of the Pagans gang were indicted on charges of large-scale drug trafficking.

The outlaw gangs are at a stage of evolution comparable with that of La Cosa Nostra in the 1920s and 1930s, according to federal officials, lacking in experience and sophistication but with a taste for violence. Like La Cosa Nostra, they are said to operate under a code of silence.

The FBI estimates that there are 600 to 800 motorcycle gangs in the country. They distinguish between these and more than 100,000 Americans who ride motorcycles for sport.

Officials use the term "outlaw" in referring to the gangs because that is how the gangs refer to themselves, Bonner said. The American Motorcycle Association in the 1960s asserted that only 1 percent of bikers were outlaws. The gangs "picked up on the term and called themselves 'one percenters' or 'outlaws,' " Bonner said.