New here! 50cc build

DAMIEN1307

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Damien I’m not over the hill yet but the view is pretty good from here!
My old joke was always, "I'm not over the hill yet, but i can certainly see the top"...lol.

Also, they always like to call these, "The Golden Years"...I don't know about you, but what i see doesn't exactly pass for gold, if ya know what i mean...:poop: :poop: :poop:...lol...It's more like the Midas touch in reverse...lol.
 

DAMIEN1307

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Don't worry about old-age, it doesn't last very long.👴
Climbing the hill to 50 is the hard part, then It's all down hill from there :LOL:
YEP...I call it "sliding down the razor blade of life"...lol...Just be careful as your hind end is sliding down that razor, that you don't make an extra slit so that your farting in stereo...lol...lol.
 

Risk Man

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Oct 28, 2021
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330
Is that piston flat on the top? @DieselTech that gasket looks like it was sealing all the way around to me, there is a little oil seepage from removal on one side. The up side has a good impression of the cylinder all the way around, shows good even torque. Half the time the gasket will be crushed on one side and not the other, the crushed side had the big kid on the production doing the torque on that side.
The piston was not "flat". there was a raised "rim" as you can see. I did a bit of honing with glass and sandpaper with the head and the jug, but when I tightened it down the first time with the new aluminum gasket, I could see light at the corners of the head. It seemed like that rim was leaving a gap (Teetering) because it is raised. So I loosened the nuts and tried to make sure I made it sit flat by rotating the torque around the head and while doing so (with a cheap digital torque wrench at 7 lbs) one of the nuts stripped at the top of the stud on the side that had the light coming through. So I am going to the hardware store today and see if I can get some 10mm threaded rod to replace that one stud.

Can I sand the raised area flat or will that change the compression too much?

I am about to toss this cheap engine and put my BBR engine I bought originally when I had no clue what I was buying or doing back in October.
 

Greg58

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Jun 3, 2012
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The head should have a raised area that seals, you will be able to see light at the corner. The head below shows the raised area.
 

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Risk Man

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Oct 28, 2021
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The head should have a raised area that seals, you will be able to see light at the corner. The head below shows the raised area.
Thanks.... I have a lot to learn!! Other than perhaps the inaccurate torque issue, that is why I stripped the stud trying to get rid of the gap :mad:
 

Atvrunner2

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Mar 18, 2021
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60
Maybe someone who knows the rod type/length will jump in and help, both of my larger engines are high pin piston, even though one is a 38mm stroke and the other is 40mm. I’ve got 3 different cylinders and all seem to be better suited for a 40mm stroke crank, I tried all on the 38mm stroke lower and port opening wasn’t near the original cylinder.
I will just make sure I have both pistons on hand. Sounds like the way to go
 
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