Malossi Primary Gear Ratio 16/40 (1:2.50) for Minarelli – more top speed, less "over-revving"

When you modify your Minarelli engine or install a tuning cylinder, significantly more power is produced – and this can (and should) translate into a higher top speed. The problem: the original final drive ratios are usually chosen so short that the stock engine can pull them easily. With more horsepower, the engine quickly "over-revs" at higher speeds; the RPMs shoot up, but the top speed barely increases.

This is exactly where this Malossi Primary Gear Ratio comes in: the gears and intermediate shafts are manufactured to a first-class standard and help you bring the final RPMs to a manageable level – while simultaneously allowing the top speed to increase noticeably. Such a setup is particularly popular on, for example, the Yamaha Aerox 50, MBK Nitro, or Aprilia SR 50 (and many other Minarelli models).

And don't worry about typical myths: a longer ratio does not automatically mean that your scooter will have worse acceleration from a standstill. In practice, slightly stiffer clutch springs are usually sufficient to compensate for this. On the contrary – if the gearbox is too short for the available horsepower, you are wasting valuable power because the engine could actually pull much more.

Advantages / Features

• Longer primary ratio for more top speed with tuned setups
• Reduces high final RPMs – the engine no longer revs up unnecessarily
• First-class workmanship of gears and intermediate shafts
• Ideal as a supplement for tuning cylinders and power increases
• Suitable for daily use: acceleration behavior can usually be easily balanced with slightly stiffer clutch springs

Technical Details / Specifications

• Dimensions: CW + MY + MA
• Ratio: 16 / 40
• Ratio: 1:2.50
• OEM Numbers (Comparison): 67 3677, 673677

Compatibility (Excerpt)

Fits many vehicles with Minarelli drives, such as Yamaha Aerox 50, MBK Nitro, Aprilia SR 50 – but also numerous other models from the list.

• Aprilia: Scarabeo 50 2-stroke (1999-2009), Area 51 50, Gulliver 50 LC water, SR 50 Racing LC water (2000), Amico 50 GL, SR 50 Stealth LC water, SR 50 Netscaper LC water, Gulliver 50 AC air, Rally 50 AC air, SR 50 LC water (1994-1997)
• Italjet: Pista 50, Scoop 50, Dragster 50, Pista 2 50, Yankee 50
• KTM: Tempo 50, Go 50, Quadra 50, Chrono 50, Ark 50 LC water, Ark 50 AC air
• MBK: Flipper 50, Booster Naked 50 13 inch, Booster 50 12 inch (2004), Nitro Naked 50, Sorriso 50, Stunt Naked 50, Booster 50 NG (1999), Mach G 50 AC air, Mach G 50 LC water, Booster 50 One 2DW
• Malaguti: Yestarday 50, F15 Firefox AC air (2004), F12 Phantom 50 AC air (2003-2006), F15 Firefox LC water (2004), F12 Phantom 50 LC water (2000, 2004), F12 Phantom R 50 AC air, F12 Phantom R 50 LC water
• Yamaha: Aerox 50 (1999), Spy 50, Slider 50 (2004), YE Zest 50, BWS Bump 50, Breeze 50, Jog R 50 AC air, BWs 50 Original SA231 (2011), BWS 50 NG (1999), Jog RR 50 LC water

Why Malossi?

Malossi stands for sophisticated technology and cleanly manufactured components in scooter tuning. With this primary ratio, you get exactly what is often missing after a cylinder upgrade: usable gearing for real top speed instead of just RPMs.