what does dual clutch multi plated in a motorcycle without a clutch lever means?

Question

cub type motorcycles without clutch levers ranging from 100-150 cc

Answer 1

If you're talking about automatic clutches on scooters.
It's a CVT clutch.
The engine drives the rear wheel via a belt.
The clutch "sheaves" spread apart due to centrifugal force of the engine RPMs increasing, which changes the diameter the belt rides on.
Here's a video of it in action.
http://auto.howstuffworks.com/cvt2.htm

Edit
After reading some of the other answers, I got a better idea of what you might be asking.
The first clutch looks like a drum brake on a car.
The engine spins the shoes.
Centrifugal force spreads the shoes apart and they grab the drum.
When the drum starts turning, it turns the conventional clutch (they're connected to each other by gears).
The conventional clutch (the 2nd one), clutch friction plates are locked together by springs, which turns a transmission shaft (I'll call that the input shaft).
The transmission gears on that shaft, turn the gears on the output shaft.
The output shaft turns the F sprocket, which turns the rear wheel, via the chain (chain & sprockets).
When shifting gears (with the shift lever - at the L foot peg), the transmission gears are moved.
In order to move the transmission gears without them colliding into each other at high RPMs of the transmission shafts, the second clutch is activated.
The clutch plates of that clutch are seperated by a ball and ramp set-up, when the shift lever is moved.
That action disconnects the transmission's input shaft from the engine.
Here's a picture of the 2 clutches.
It'll give you and idea of what they look like and how they work.
http://www.mrcycles.com/
Go to - Kawasaki ATV Parts - 1990 - KLF220 - Clutch

Answer 2

It has a centrifugal clutch connecting engine primary drive to a second multi plate clutch activated by the foot lever(conventional type) As you change gear the foot lever disengages clutch
It also means you can pull wheelies by holding foot lever down and revving engine, slip foot sideways and bike can flip over on top of you.
So, only take foot off lever at idle after putting it into first gear.

Answer 3

is simillar to auto transmission in cars.
this bike can start with gear engaged.beware
You are advised to engage your gears at idle speed or you will be thrown off from the bike.
be carefull with this bikes.
easy to handle but also dangerous if mishandled.