moin boys, have an urgent problem.. front off,I drive a piaggio nrg mc3. I drove today for the first time with an ori.runner exhaust as they have no throttles from the factory.. after a stretch of c.a 5-10km the exhaust gets warm and it starts to exaggerate from the exhaust to smoke.. it is a white smoke, but it smells quite after burnt rubber b.z.w plastic. it gets really extreme only when I drive faster so from 60kmh.. actually have only the ring can you help me? I really don’t know what it can be that the exhaust after a while really starts to smoke.. achja the exhaust sit also not new,have it from ebay and it has already set rust.. please help me further. mfg