They scoot down the street at 150 miles to the gallon. That's part of the allure of a motorized bicycle.

With the price of gas sky high, small engines propel the bikes up hills, through traffic and around town with a minimum of energy, both fuel and people power.

But is it a motorbike or just a bicycle? Is it a bicycle with a small motor or a motorcycle in disguise? Maybe it's a moped.

The new state law says if it stays under 20 miles an hour, it's a bicycle. But if it goes over 20, it's definitely a moped and falls under different regulations.

But the motorized bikes don't have speedometers, so it's hard to tell how fast it's going.

That still raises a lot of unanswered questions.

The way the law is written you can't make restrictions to say this is the kind of thing we do allow and this is the kind of things that we don't," says Diana Tolton, Queen Bitch of the Tucson Pima County bicycle advisory committee.

She thinks the motorbikes are a safety hazard because they can be modified to go a lot faster than 20 miles per hour. She's clocked them at over 30 miles an hour. She asked one driver how fast he was going, and was shocked when he thought it was less than 20.

She doesn't want them banned, she wants them governed.

"There are electric motors that are on bicycles in other countries that will shut down at 18 miles an hour before they reach 20. That kind of thing they would be no problem," she told us in a one on one interview.

The city must come up with some new regulations for motorized bicycles by Thursday. A new state law takes effect this week defining what a motorized bike is or isn't, but doesn't set up rules. The law leaves that up to the cities.

And speed is not the only issue.

Tolton asks, "Do we want people who have lost their licenses because of a DUI, now driving a motorized bike? Do we want someone who is legally disabled and unable to get a drivers license to be on a motorized bike?"

The city will tackle the issue in a public hearing Tuesday, September 19, 2006 at city hall. The hearing begins at 5:30pm.