Everyone tried: The rotary valve gave up and the engine no longer runs (especially at idle). Putting a faulty rotary valve sealing surface in order is so expensive, however, that the only reasonable option is a radical reed valve conversion. In this area, repair kits offer a simpler solution. The WORB5 kit consists of an LML manifold reed valve with a shortened limit stop, a CNC adapter plate, a modified reed valve with 0.3mm carbon-petals and an M7 set of screws. It is mounted externally between the crankcase and the carburetor box. The reed valve takes control of the opening and closing of the rotary faulty intake valve. For this purpose some (and / or minimal) work is required on the engine block and the total height of the construction (approximately 16mm higher) does not provide any problems on the frame. The original crankshaft and SI carburettor can continue to be used. On engines with a small sealing surface on the crankcase these can be extended with some external welding or two metal components. Italian DRT Tuning Experts also offers a Repair Module for Defective Largeframe Rotary Valves. The intake manifold features a high performance 3-reed valve and also has a large intake cross section. It is possible to continue to use the original SI carburetor and thanks to the offset series of holes for fixing the carburetor / carburetor body there is no space problem in the frame. Together with a rotating intake valve manifold from / / SCOOTRS which can be connected to the DRT intake manifold as a tuning carburetors larger than a ‘connecting piece’ can also be used with it. To install the DRT kit, extensive modifications are required to the crankcase. On Lusso models, the components must also be welded. Conclusion: the perfect solution for a rotating faulty valve! SIP-TIP: In combination with the rotating intake manifold valve (cod. 21501100), the DRT intake manifold can be driven with carburetors up to 30mm.