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The unfortunate answer to my R69s problems

166926

New member
So, after barely holding 30 psi on the rider's left cylinder, and 60 pst on the right, I dug into the bike today. Here's the rider's left cylinder....
 

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  • Rider's Left Piston.jpg
    Rider's Left Piston.jpg
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Here's the rider's left cylinder head. I did an old fashioned leak down by putting gas in it, and after 10 min, it still held, so I may be OK there... The right side pics didn't come out, but it was carbon-y, not nicely polished by bits of piston. It also held the gas.

So, next stop, pulling pistons. You think the valves are OK? Supposedly they are brand new, with hardened valve seats....
 

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  • Rider's Right CH.jpg
    Rider's Right CH.jpg
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So, do I see that correctly in the left piston crown...something has blasted part of it away? I can see where the compression would be down...I'm surprised there wasn't a breach through to the inside.

As for the valves, I haven't seen many of them, but it sure looks like thoses valves are sunk a bit into the head. Usually, the valve sits a bit more proud of the seat...maybe it's just the picture. It might be wise to have a professional look at the surfaces.
 
You do see correctly. Burned away. The other side is harder to see, but it too has been burned up, just not as bad. I think it is the pics that make it look like the valves are sunken.
 
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