Peugeot Elyseo, Trekker, Vivacity, Speedfight, Buxy & Squab Scooters
These motors are basically identical except for water-cooled cylinders and water pump driven from the flywheel right-hand side of the motor, replacing the fan on the air-cooled engine and approximately 10% higher gearing in the water-cooled motors.

Derestricting
Despite the many differences in the bodywork and exhaust styling, they are all restricted in the same way

By the exhaust being fitted with a resonant tube (a blind pipe attached to the front pipe) that should be cut off and welded up. This improves power and rev-on.
By a gearing restrictor in the variator body. This takes the form of a large diameter plate next to the roller drive plate in the rear of the front pulley. It just requires removal of the variator body cover and removal of the plate and reassembly.

If these derestrictions are done correctly the differences shown in the dyno curves will be apparent.

Dyno photo Fitting a 70cc Cylinder Kit Dyno graph showing the different stages carried out on the same Peugeot 50cc scooter.

We would normally fit a slightly larger main jet, approximately size 76/78 if size 72/74 was originally fitted.
To improve power output further the next stage is to fit a 70cc cylinder kit. These are available very cheaply for the air-cooled and water-cooled motors.
The DR air-cooled cylinder kit comes complete with a size 80 main jet for the carb and fits using the original head. Power is improved as shown on the dyno graph.