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Big Bore gaskets

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Old Mar 29, 2015 | 05:57 PM
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Default Big Bore gaskets

I have a 1993 fxlr with big bore kit installed. I have no information on the work that was done as it was already done when I purchased the bike last year. I am wondering how to find out what size kit was installed and how to purchase the correct gaskets. I will be doing base gaskets and up.

Thank you in advance
 
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Old Mar 29, 2015 | 06:14 PM
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The only gasket that will be different for your big bore will be the head gaskets. Determine your displacement by measuring your cylinders and order a Cometic or James top end gasket kit with the proper head gasket size and thickness.
 
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Old Mar 29, 2015 | 06:28 PM
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Thanks for your reply. That sounds simple enough. Just so I'm clear, use a dial caliper to measure the widest part of the cylinder opening on get the gasket that is for that size?

Thanks again
 
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Old Mar 29, 2015 | 07:39 PM
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That will work, and order a gasket as close to the opening as you can without being smaller - do not want an overhang.
 
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Old Mar 29, 2015 | 07:43 PM
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What is the stock piston size. Just so I know how much bigger mine is than stock.
 
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Old Mar 29, 2015 | 10:20 PM
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Looks like 3.46": http://www.mbike.com/harley-davidson...er-custom/1993
 
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Old Mar 30, 2015 | 07:06 AM
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Originally Posted by dfwhockey17
The only gasket that will be different for your big bore will be the head gaskets. Determine your displacement by measuring your cylinders and order a Cometic or James top end gasket kit with the proper head gasket size and thickness.

not true,base & head gaskets will be different for a EVO big bore.when you get the heads off,measure the bore & order gaskets(it will be either 3.625 or 3.812) then just order gaskets
 
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Old Mar 30, 2015 | 07:28 AM
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Thank you!
 
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Old Mar 30, 2015 | 02:11 PM
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S&S is 3.625", Sputhe Engineering is 3.780", and Axtell or Hyperformace is 3.812", unless it is a custom bore size.
Scott
 
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Old Mar 30, 2015 | 02:43 PM
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Thank you. Is there usually any identifying marks on the jugs to show brand, size or kit? Obviously that would be to convenient.

This may be a dumb question, but forgive me because i have never been inside any part of a Harley engine - Yet. I remember hearing once that they had oval pistons or cylinders. Is this true?

Thanks again.
 
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