any idear where

[davesatan]

i can get a baffle tube to fit down a reliant tail pipe i think the internal diameter is 30mm

[Blackjack]

Usually, exhaust pipe is in inch sizes including most jap bikes. So you're probably looking for either 1 1/4" (about 31.75mm) or 1 3/8" (about 34.925mm). Probably get a VW baffle up there, which is available from most exhaust centers and VW specialists fo a couple of quid or so.