Squish clearance 250yz

ezmoto
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ezmoto
After piston change my bike started pinging. I measured the squish and it’s at 1,14mm, and I run with a Rinaldi head which makes better compression... should I get a bigger head gasket?? I heard 1,3 mm is minimum for a 250 2 stroke, but can’t find much about it. But this would explain the pinging.
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FGR01
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FGR01 7/5/2020 7:43am
7/5/2020 7:43am
Don't think you can do a thicker head gasket since the YZ250 uses o-rings. Unless your Rinaldi head eliminated the o-rings and now uses a flat gasket.

When you changed the piston, is it the same type piston as before?

That squish does not sound overly tight, but you also have to consider head chamber volume. It sounds like your total volume is probably low.
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ezmoto
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ezmoto 7/5/2020 8:34am
7/5/2020 8:34am
FGR01 wrote:
Don't think you can do a thicker head gasket since the YZ250 uses o-rings. Unless your Rinaldi head eliminated the o-rings and now uses a flat...
Don't think you can do a thicker head gasket since the YZ250 uses o-rings. Unless your Rinaldi head eliminated the o-rings and now uses a flat gasket.

When you changed the piston, is it the same type piston as before?

That squish does not sound overly tight, but you also have to consider head chamber volume. It sounds like your total volume is probably low.
Im putting in a new gasket.. i heard 1,14 mm is very tight, and the rinaldi doesnt help it :/ Im running a vertex now

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