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Discussion Starter #1
Hello all,

So I saw I few piston install video where they mention that the piston rings gaps have to be checked on each ring before putting it on the piston.
I have the english version of the kitaco install plan for the neo kit, but they don't mention that anywhere on it.

So, for those who installed the same kit:

Are the piston ring gaps pre cutted to the right size and I can just put them on the piston directly?
Or do I have to check those gaps before installing the rings?
 

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Check the end gap by putting the ring in the cylinder and pushing it down with the piston till it seems level all the way around the cylinder and measure the gap should be I think around .28mm for top ring and around .30mm for the second compression ring. Don't quote me but check what your kit recommends.

For me I line up the compression ring gap one on one side of the piston connecting rod pin hole and the other second compression ring on the other end of the piston connecting rod pin hole.

The oil rings just keep the ring ends at lease 120 degree away from each other's gap.

make sure to use a lot of engine oil on the cylinder wall and connecting rod pin. Don't ever install the piston in the cylinder dry.

good luck

 

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Discussion Starter #3
That's the thing. It s not mentionned at all on the kitaco installation guide from the kit itself. They just talk about that the gaps shouldn't be aligned on the same line. (see pic) so it's confusing
87166
 

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Its not explicitly mentioned, but if you look at the pictures, all the ring gaps are clocked correctly.
 

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I had to gap the top ring. The other two were in-spec. Ring gap is a standard part of building/blueprinting a motor and you need to do this. The spec. is not given by Kitaco because this is up to the builder.
 

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Discussion Starter #7
Yeah that's why I asked before installing them incorrectly
Thx for your reply's guys!
I'll look up ring gap specs and I'll check all the gaps before installing the rings.
 

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Discussion Starter #8 (Edited)
So here are the gaps spec I've found:

Top ring gap should be 0.279 mm (0.011" )
Second ring gap should be 0.376mm (0.014")

Is this correct ?
also, I couldn't find the info => Oil rings gap size doesn't matter?
 

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I think the oil ring overlaps itself, so no gap.
 

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So here are the gaps spec I've found:

Top ring gap should be 0.279 mm (0.011" )
Second ring gap should be 0.376mm (0.014")

Is this correct ?
also, I couldn't find the info => Oil rings gap size doesn't matter?
Where did you find this info?
 

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Discussion Starter #11
From the hardracing video about ring gap measurements, which were also done on a 180cc piston
Partzilla gave about the same measurements too for a 170cc piston

I couldn't find any precise info in mm, but my feeler gauge gives both mm and inch and those are the corresponding values.
 

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From the hardracing video about ring gap measurements, which were also done on a 180cc piston
Partzilla gave about the same measurements too for a 170cc piston

I couldn't find any precise info in mm, but my feeler gauge gives both mm and inch and those are the corresponding values.
Looks good enough for me, I set my top ring at .012 and the second ring between .013-.014 and this is on my Takegawa 181-4v engine.
 

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Piston install instructions are insider the piston box that kitaco provides. It isnt a kitaco part.. rings are marked
 
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