Blast variator fixed half-pulley for Minarelli 50 Booster, Aerox, F12, F10, Ark

The Blast variator half-pulley is the fixed half of the drive pulley for Minarelli 50 engines fitted to the Booster, Aerox, F12, F10 and Ark. It comes with the variator plate and is the part to fit when the original half-pulley is worn or damaged.

Together with the moving half-pulley, rollers and belt it forms the scooter's variator: a half-pulley in good condition keeps the belt sliding smoothly and the drive fluid, from take-off to top speed.

Features

• Fixed half-pulley with variator plate
• For Minarelli 50 type engines
• Silver finish
• Diameter 95 mm, centre bore 13 mm
• Blast (BCR) brand
• Replacement for the scooter CVT drive

Applications

This half-pulley is listed for the following 50 cc scooters with Minarelli engines:

• Yamaha Aerox 50
• MBK Booster 50
• Malaguti F10 and F12 (air and liquid cooled)
• Beta Ark 50 (air and liquid cooled)

Check your scooter's model and version: if in doubt, compare the fitted half-pulley with the one on this page before ordering.

What the fixed half-pulley does

The fixed half-pulley sits on the crankshaft and, with the moving half-pulley, determines how the belt slides in the variator. The belt faces wear with mileage: a scored or marked surface damages the belt and worsens acceleration.

When to replace it

Replace it when the surface the belt runs on is scored, marked or worn, or when you find the plate or seat damaged during a variator overhaul. It is worth checking the belt and rollers too.

Fitting and tips

• Remove the variator cover and the belt following the workshop manual for your model
• Lock the crankshaft with the proper tool and undo the pulley nut
• Replace the half-pulley and check the variator plate, then refit to the specified torque
• Check the belt and rollers before closing the cover

Frequently asked questions

Which scooters does this half-pulley fit?

50 cc scooters with Minarelli engines: Yamaha Aerox, MBK Booster, Malaguti F10 and F12, Beta Ark.

Is the variator plate included?

Yes, it is a fixed half-pulley with variator plate.

Should it be replaced with the belt?

If the half-pulley is worn it is worth checking the belt and rollers too.

Is a special tool needed?

You need a tool to lock the crankshaft, as shown in the workshop manual.