when riding my dt125x if i ride it hard to the top of the revs thers a black oily substance oozing from the exhaust muffler also will a dep exhaust from a 2003 dt125 fit 2005 dt125r
if its got a dep pipe you cannot take the baffle out unless you drill out the rivets,using caustic soda is an option as peesian says but caustic soda is very corrosive and will mark and damage anything it touches including you,also its not that effective.the best thing to di is have it cut open and the blocked areas removed alltogether and then welded backup again.
adam bike doctor
June 2010
remove your exhaust and fill with caustic soda overnight to decoke and remove baffle first to wire brush
peesian
June 2010
its just burnt/unburnt oil dont worry about it ,if you rode it hard all the time you probably wouldnt see it but its basically a build up of mixed burnt and unburnt oil in the exhaust and when you really ride it hard it will blow it out through any gaps and also the tail pipe.
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