Gotta be a joke. Right? Elaborate if you can. The only tune for the rd28 with electronical pump, is a piggyback tuneup box. Loading that vehicle with luggage and then driving off, is wearing that clutch down every time you start, and it barely reaches a 100 km/t. Airing it down to 2kg, or bar, is like putting 200kg on the roof and a horse trailer behind it.