WJ-Tuning is a specialist retailer and tuning workshop focused on performance parts for Piaggio and Gilera Maxi scooters, particularly 125–180cc models. The brand develops and tests its own components, alongside products from other manufacturers, with an emphasis on helping riders build and refine complete scooter setups. Its catalogue covers engine and drivetrain parts, including cylinders, crankshafts, CVT components, clutches, gears, bearings and ignition parts. Customers can also find intake and fuel-system components, cooling parts, bodywork, suspension, brakes, tools, fluids, custom exhaust products, software and tuning files.

Beyond selling parts, WJ-Tuning offers practical services and planning tools. Its Setup Builder helps customers assemble a compatible configuration, while the exhaust designer supports custom exhaust planning. The workshop provides tuning and setup assistance, including one-to-one tuning sessions, as well as services such as cylinder honing, engine rebuilding, welding and blasting. WJ-Tuning says its products are developed, tested and used by its own team, with testing both on a dynamometer and on the road. The business ships on Mondays, Wednesdays and Fridays.