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Old 05-07-2017, 11:53 AM   #1
spldart
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Nod Just pulled all the China engine parts (see puked guts out)

Pictures will follow shortly

That rapping sound from inside the engine got so loud that you could hear it echoing
off of cars stopped in traffic with yah so a tear down was imperative.

New China gaskets, rigged, and all the old parts got cleaned up and cyl got quick hone.
Rigged means I stacked to cylinder base gaskets and I added two shims to the head
gasket as to maintain reasonable deck height. *see issue in 'puked her guts out' thread*

What I found during tear down...
1) Gasket was starting to blow out in the same place.
I'm not surprised as I had seated it 3 seperate times. That's a no no.

2) Piston pin was a tiny bit loose in connecting rod in a rocking fashion.

3) Piston pin retainer clips lost most of their tension. I was able to pull them with a
fingernail!

4) More carbon buildup than expected and mostly around intake side.
Guess I'll use my stem seals on the intake valves sometime soon.

5) The head crack hasn't grown any. I'm very fortunate the cracks terminus's both end
in large radius's.
Any structural engineers out there will know what I'm talking about

Old pin is very snug on rod and piston. Old clips are very high tension. New gasket
went in with one shim on top and one on bottom which should help sealing.
Bike started on first try. No bad noises.
Later took it a few blocks test ride and it was still sounding great.
Later today I'll put some miles on it.

Pictures coming in minutes.



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Old 05-07-2017, 11:55 AM   #2
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Chinese cylinder top. You can see at the front where the gasket was starting to blow
gasses through.

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Old 05-07-2017, 11:57 AM   #3
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For only a couple thousand miles or so I sure got a lot of carbon built up on the chinese
piston.
Rings were starting to get to much gap movement too

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Old 05-07-2017, 11:58 AM   #4
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Old 05-07-2017, 11:59 AM   #5
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The infamous CRACK!!!

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Old 05-07-2017, 12:01 PM   #6
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I found that this journal upper half and the other cam journal lower half had some slight
wear marks showing. Dunno how normal that is for this many miles.

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Old 05-07-2017, 06:40 PM   #7
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Put ten miles on it.
Minor oil leak. Fixed that just now.
Slightly down on power. Betcha my mileage goes back down to 68 mpg too. meh

But!
It sounds perfect. Absolutely perfect.
Like new.
Wonder how long this will last XD
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Old 05-08-2017, 12:12 AM   #8
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Hope this is the last time for you. You are due for some success.
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Old 05-08-2017, 10:04 PM   #9
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I'll put it aside the gremlin bell already there.

The marks are new since the rebuild a couple thousand miles ago.
Since the noise is gone I've dismissed them at this time as a problem.

Now I'm gonna obsess about the carb.
Cold start and running for the first 2 or three miles is a 6!7ยข#!
Used to run better long time ago.
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Old 05-09-2017, 09:42 PM   #10
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Update.
I was having a ball today.
Squirting through traffic on a motor I finally trust again.
Fun?
IT'S BACK!1!!1
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