Squish 250yz to tight?

ezmoto
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ezmoto
Hello,

So i just changed piston in my 250yz to a Vertex. The Vertex base gasket is 0.5 mm and i dont know what the OEM was. But i measured the squish to be at 1.14 mm (0.0045 inches) and im worried that this is to tight with the Rinaldi head i have on. It pulls like CRAZY, but should i go with a thicker base gasket? Or should i be happy with this squish? Smile

Bikes done 75 hours total
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Melicar
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Melicar 7/9/2020 5:59am
7/9/2020 5:59am
Yes
ezmoto
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ezmoto 7/9/2020 10:59am
7/9/2020 10:59am
Melicar wrote:
Yes
Sooo, i should be happy with the squish?
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motox11
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motox11 7/10/2020 4:49am
7/10/2020 4:49am
That squish is fine.
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40
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40 7/12/2020 11:14am
7/12/2020 11:14am
ezmoto wrote:
Hello, So i just changed piston in my 250yz to a Vertex. The Vertex base gasket is 0.5 mm and i dont know what the OEM...
Hello,

So i just changed piston in my 250yz to a Vertex. The Vertex base gasket is 0.5 mm and i dont know what the OEM was. But i measured the squish to be at 1.14 mm (0.0045 inches) and im worried that this is to tight with the Rinaldi head i have on. It pulls like CRAZY, but should i go with a thicker base gasket? Or should i be happy with this squish? Smile

Bikes done 75 hours total
Be aware that 1.14mm converts to 0.045". Thats 45 thousandths of an inch. Very good squish number.
You have posted 0.0045". Thats 4 1/2 thousandths of an inch. Way, way too tight.
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H4L
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H4L 7/12/2020 6:18pm
7/12/2020 6:18pm
Yes, as mentioned above the engine should be fine. That is actually an ideal squish # to shoot for.
digger
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digger 7/12/2020 7:52pm
7/12/2020 7:52pm
That 1.14mm squish will be fine, from a mechanical stand point. Just be aware that you are more than likely going to need to use some race fuel, depending on what the heads combustion chamber volume is.
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