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Old 06-12-2019, 02:39 PM
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Last Online: 06-14-2019 05:47 AM
Location: Idaho
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Usflag 04 YFZ 450 no compression

Back story:
So I started leaking some oil and decided to get a gasket kit. I have an Athena 98mm stroker kit fyi. Almost everything went back together nicely at first. When I initially started it the compression was too high to turn it over enough to start it. I assumed this was a timing issue not allowing that exhaust cam to auto decompress while starting. Then things went wrong apparently. I did break a bolt on the cam cover that I had to have drilled out (had to remove head) and the decompression plug fell out and got lost but I replaced that. When I started it back up after getting it together there was no compression at all. It just turns over. I flipped the cams just in case they were 180 off but no change. I rotated the crank and the lobes are compressing valves as they should. I know it's timed right per spec (exhaust marks at 9 and 11 and intake 1 and 3). I even took out the spark plug and made sure piston was TDC and lined up with timing mark. Still no compression. When I turn it over and stick my hand over exhaust pipe there is an alternating suck/blow corresponding with a complete cycle. Does this sound like a stuck valve to any of you? Or something else? Before I pull the head back off I thought I'd seek some advise. Thanks in advance.
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