piston to bore clearance

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handofdave
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would an excessive piston bore clearance of 0.3mm cause my bike not to start from cold?
bristolmod
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I would think so as its twice the max allowable clearance. I assume the ring gap is also excessive as well? Is there rather a lot of piston slap when you get it to run?

Whenever I get a cylinder rebored, I go for 3 thou (in old money)

Chris
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handofdave
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new rings but gap is excessive,would the wear stop the engine from sucking the fuel in,when i finally get it running and warmed up it starts first kick when hot,by the way it is a short rod suzuki
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ArmandTanzarian
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handofdave wrote:would an excessive piston bore clearance of 0.3mm cause my bike not to start from cold?

You probably know this but I'll mention it anyway because I didn't. If you check the clearance with a feeler gauge, remember to halve the value because the other side of the piston will be touching the cylinder.
Meus Lambretta est non infractus. Is est quietus.
Muppet
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so im lookin at 12 thou feeler for 6 thou cleerence?
C’est la vie
handofdave
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ArmandTanzarian wrote:
handofdave wrote:would an excessive piston bore clearance of 0.3mm cause my bike not to start from cold?

You probably know this but I'll mention it anyway because I didn't. If you check the clearance with a feeler gauge, remember to halve the value because the other side of the piston will be touching the cylinder.
no i didnt know that,thanks for the info,so the clearance is 0.15 would that stop it from starting?
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wack 63
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The cold weather certainly wont help.Once the fuel hits the cold engine parts it's likely to condense and introduce water moisture into the cylinder which won't help starting.
camel
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ArmandTanzarian wrote:
handofdave wrote:would an excessive piston bore clearance of 0.3mm cause my bike not to start from cold?

You probably know this but I'll mention it anyway because I didn't. If you check the clearance with a feeler gauge, remember to halve the value because the other side of the piston will be touching the cylinder.
Why would you half the value?the clearance is the difference between piston and barrel.not half the difference
camel
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Muppet wrote:so im lookin at 12 thou feeler for 6 thou cleerence?
No a 12 thou feeler gives you 12thou clearance
Muppet
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camel wrote:
Muppet wrote:so im lookin at 12 thou feeler for 6 thou cleerence?
No a 12 thou feeler gives you 12thou clearance
are u sure :? what if I hold the pot upside down and measure it left handed :ugeek:
C’est la vie
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