Doppler pulley Open disc clutch Peugeot 103

Doppler Open moped racing pulley

The Doppler pulley from the Open series offers an innovative clutch for classic mopeds, namely a motorcycle multi-plate clutch for vintage mopeds. The concept is completely new, the performance is outstanding - a revolution for the moped racing scene.

For Peugeot 103 MVL / SP / Vogue.

Doppler Open - The motorcycle clutch for mopeds

The conventional centrifugal clutch with clutch shoes is replaced by clutch discs. Basically, it is a disk clutch like on a motorcycle, but the Doppler Open works 100% automatically, as there are roller weights like in a CVT. The result is an extremely efficient and compact clutch unit. Throttle response is direct and progressive.

Note: The more torque and power the engine has, the heavier the rollers should be to prevent the disks from slipping.

The vehicle is started by engaging a bolt; three points offset by 120° accommodate the bolt and thus shorten the distance required for starting. The mechanism is disengaged automatically after the engine has been started.

This technical solution makes it possible to dispense with a freewheel bushing in favor of mounting on bearings. This has two advantages:

• The ability to move the vehicle in both directions when stationary without engaging the engine.
• Reduction of play-induced deformation.

Doppler's revolutionary clutch system is perfect for racing or hybrid engines (conversions with Derbi or Aerox cylinders), for dynamic stars and acceleration with optimum performance even when the engine is warm.

Doppler Open - Best materials and optimum design

The pulley is made entirely of high-quality aluminum. The anodized surface ensures high resistance to oxidation.

The 12 screws on the pressure plate ensure even pressure. The milled heads are designed in such a way that automatic loosening is virtually impossible.

Scope of delivery Doppler Open clutch:

• 1 aluminum pulley D. 213mm
• 2 friction disks / 3 plain disks
• 1 steel sprocket
• 1 pedal shaft
• 2x 12 rollers (10g for original setups / 16.9g for racing setups)
• 6 push springs
• Bearings and needle bearings, screws, nuts, pins etc.