does your peugeot 103 not idle? does it die when you slow down? here's the problem: your clutch is dirty, or broken, and must be reassembled.
stuff your cylinder with nylon rope fed through the spark plug hole to keep it from turning over
take off the clutch cover
take off that giant bolt
take apart the clutch (it's the big disk next to the engine, not the variator. the variator is the smaller disk.)
take notes to make sure you reassemble it correctly
clean everything with brake cleaner EXCEPT the blue-gray disk with teeth around the outside (drive disk). that disk may actually be shattered. if it is, call moped warehouse and get a new one for $22
grease the roller bearings that surround the drive shaft. do not grease the ball bearings.
lightly oil everything exept the drive disk.
reassemble using your notes.
everyone who has a peugeot has probably had idle problems. this is why. everything will work fine when you fix the clutch, and you'll feel like a kid again. post your results. 9-6 bitch.