Malossi MHR Contrast Spring (white, reinforced) – clean variomatic tuning for Minarelli

With the Malossi MHR contrast spring in white (reinforced), you can specifically tune the variomatic of your Minarelli setup. Malossi offers various hardness levels – because the art of tuning is finding the correct combination of contrast spring, variator weights, and clutch springs. Especially for scooters like Yamaha Aerox, MBK Booster, or Aprilia SR 50 (depending on the engine/variant), a suitable spring often makes the difference between "running somehow" and clean power transmission.

Important: If your V-belt is slipping, you should definitely choose a harder contrast spring. At the same time, however: Too hard can in turn have a negative effect on the power output. The white, reinforced Malossi MHR spring is therefore ideal if you want to bring your setup towards better tuning and more reliable shifting behavior – without overdoing it blindly.

If you are stuck while tuning, feel free to check an online community: almost every conceivable combination of springs and weights has already been tested there.

Advantages & Features

• Reinforced contrast spring (white) for Minarelli setups
• Helps with slipping V-belts through higher clamping pressure
• Enables finer tuning together with variator weights and clutch springs
• Proven Malossi MHR quality for reliable function
• Suitable for many popular scooters, e.g., Yamaha Aerox, MBK Booster, and various Minarelli models

Technical Details

• Type: Contrast spring / Contrast spring / Variomatic spring
• Version: MHR
• Color: white
• Version: reinforced
• OEM numbers (for comparison purposes only): 29 7047.W0, 297047.W0, 297047W0

Compatibility (Vehicle List)

Fits many vehicles with a suitable Minarelli setup, such as Yamaha Aerox / Jog, MBK Booster / Nitro, Aprilia SR 50, as well as numerous other models from the following manufacturers:

• Aprilia (e.g., Amico 50, Scarabeo 50 2-stroke, Mojito 50 Morini engine, SR 50 LC/Stealth/Funmaster, Rally 50, Sonic 50, Gulliver 50)
• Generic (e.g., XOR 50, XOR2 50, Ideo 50, Jump 50, Vendetta 50, ROC 50)
• Hyosung (e.g., SF B 50, Super Cab 50, Avanti 50, SB 50 Cab)
• Italjet (e.g., Velocifero 50, Dragster 50, Formula 50 AC/LC, Torpedo 50 2-stroke)
• KTM (e.g., Tempo 50, Go 50, Ark 50 AC/LC, Chrono 50)
• Keeway (e.g., Matrix 50, Focus 50, Hurricane 50, RY6 50, F-ACT 50, Venus 50)
• Longjia (e.g., LJ50QT-K, LJ50QT-H, LJ50QT-F, Zero One 50 2-stroke)
• MBK (e.g., Booster Spirit, Booster X, Nitro 4, Mach G 50, Stunt, Target 50)
• Malaguti (e.g., F10, F12 Phantom, F15 Firefox, Centro 50 Minarelli engine, Ciak 50 2-stroke)
• PGO (e.g., Star II 50, Comet 50)
• Rieju (e.g., First 50, Windy 50)
• Suzuki (e.g., Katana 50 AC/LC, Address 50, Sepia 50, Street Magic 50)
• TGB (e.g., Laser 50, 303R 50, Delivery 50, Acros 50, 101S 50)
• Yamaha (e.g., Aerox / Aerox R 50, Jog / Jog R, Neos 50 4-stroke, Slider 50, BWS/BWs 50)

Why Malossi?

Malossi has stood for precisely developed tuning and adjustment parts for decades. Especially with CVT setups, a suitable Malossi spring ensures reproducible behavior – ideal if you don't want to ride your scooter (e.g., Yamaha Aerox or MBK Booster) "roughly," but cleanly tuned.

Note: The OEM numbers serve for comparison purposes only.