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chopp124
10-12-2011, 07:39 PM
i have had a hybrid since 99 with the yz400 motor so im not completely retarded but this is a 426 dirtbike im working on new plated cyl used but mint piston checked everything tor it apart twice tailpipe smokes like its on fire and oil drips from it any ideas anybody? i cant find anything wrong no cracks nothing

josborn
10-14-2011, 03:41 AM
valve seals are shot

chopp124
10-14-2011, 11:53 AM
im trying those first have head torn down cant imagine this much oil getting past new plating and piston with 1/2 hr on it

chopp124
10-20-2011, 08:02 PM
was bad seals