New York's battle of the bikes is heating up again.

On Tuesday, activists with the environmental group Times Up! were crowing victory over the City's decision to quietly drop its lawsuit seeking to ban the monthly Critical Mass bike rides.

While that's no doubt a big relief for Times Up! and the four volunteers named in the suit, who were facing possible contempt of court charges for helping to promote the mass rides, city lawyers aren't conceding defeat.

Rather they say the lawsuit was simply "mooted out" by the NYPD's new parade rules, which went into effect February 25.

"The suit was premised under the old parade permit rules, which are no longer in effect," city attorney Gabriel Taussig explained.

But Taussig would not rule out filing a whole new injunction against Times Up! and other Critical Mass fans if they don't abide by the NYPD's new regs, which require any procession of 50 or more pedestrians, bikes, or other "human-powered" vehicles to obtain a permit to be on the street.

"We can enforce the new rule in a whole host of ways, including injunctions, arrests, and summonses and whatever else is appropriate under the circumstances," Taussig told the Voice.

When asked to elaborate, Taussig sent us this:

A person who fails to comply with an order to disperse after parading without a permit can be charged with a misdemeanor, which is punishable by a fine up to $1,000 and imprisonment up to one year. A person participating in a parade for which a permit has not been issued can also be issued a notice of violation to be heard at the Environmental Control Board, which can result in the imposition of a civil penalty of up to $25.

So expect something of a showdown at this Friday's Critical Mass – the first ride since the new regs went into effect.

Times Up! members and many other bikers say they're undaunted by the new "50 or more" scheme and plan to ride anyway. They insist "bikes are traffic too" and don't need permits, regardless of how many folks choose to pedal together.

Also riding is Lower East Side Councilwoman Rosie Mendez, who plans to roll in a pedicab to protest both the NYPD's parade rules and the restrictive new pedicab law that the City Council passed last month. (Mayor Bloomberg has until Friday to either accept or veto the Council's pedicab curbs, which critics say fly in the face of his administration's new green agenda.)

Mendez says she's drafting a bill to replace the NYPD's parade scheme with something more free-speech friendly.

"I believe that the NYPD's continued attempt to regulate our free speech is unnecessary and continues to infringe on our First Amendment rights," she wrote in a press statement. "We are clear that these regulations are drafted solely to target Critical Mass, but in doing so the NYPD goes so broadly it will having a chilling effect on all New Yorkers."

Mendez will be speaking out in Union Square right before Friday's ride with Norman Siegel and members of Assemble for Rights NYC.

Meanwhile, the Five Borough Bike Club filed suit in federal court Tuesday to prevent the NYPD from enforcing the new parade rules at all.

There's a hearing scheduled for Thursday afternoon, when the judge will decide whether to grant a preliminary injunction that would preempt any ticketing or arrests at Friday's Critical Mass.

5BBC members said they felt compelled to intervene to safeguard the group rides they host throughout the city. Writes 5BBC prez Ed DeFreitas on the 5BBC website:

"Suing city government is not one of the ordinary roles of the 5BBC. But organizing group bicycle rides is. The NYPD's parade rules essentially outlaw large bike rides, under the dubious claim that bicycle rides are a danger to public health and safety . . .

"We could have stood by, ignored the new rules, and let the police arrest bicyclists at Critical Mass and hoped that they wouldn't come for us. But the 5BBC board decided that we could not do that, not when the civil rights of all bicyclists in New York City and indeed group bicycling itself was under attack."

In the lawsuit, 5BBC members take issue with having to lay out the exact street route and destination of their often "open route" rides, and say they've found the process for getting permits "hopelessly cumbersome and disorganized."

They also object to language in the regs barring large processions from streets "ordinarily subject to great congestion and traffic,"—i.e. just about everywhere in New York.

Among the plaintiffs is Kenneth Jackson, a Columbia University prof who leads a popular "History of New York" bike tour through Manhattan and Brooklyn that draws as many as 250 students each fall. (They ride three-abreast at night when traffic's down). Jackson and others say group riding is safer and fear the new rules could put a crimp in their currently unpermitted "urban explorations."

Left out of this street fight is the whole question of whether Critical Mass's headlong clash with the NYPD has in effect prompted the City to write a bad rule for everyone. Unable to get an injunction to stop one kind of ride, the NYPD has now expanded its rule-making to cover all sorts of activities.

"The City is confidant that the new rules accommodate the needs both of individuals who seek to participate in parades, including group bicycle rides, and of those who wish to use the streets for travel," responded senior attorney Sheryl Neufeld in a press statement.

Yeah, but aren't group bike rides a form of travel?