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Big bore

   
Old Jan 31, 2015 | 01:18 PM
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Default Big bore
I have 88" twin can b model motor for a 2001 FatBoy and am wanting to know it I can bore the jugs out to a 97" and just buy new Pistons for the bike? Has anyone ever done this or know if it's possible
 
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Old Jan 31, 2015 | 01:33 PM
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we bore to 98" all the time with stock HD cylinders,not a problem.
 
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Old Jan 31, 2015 | 01:51 PM
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Default Case or not....
When boring an 88" to 98" do you have to bore the case as well or is it just the max you can do to the jugs without touching the cases?
 
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Old Jan 31, 2015 | 02:07 PM
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3.937 is as big as you can go. This yields the 98."
Kirby, above, or Scott at Hillside are the guys to talk to. Got mine from Hillside. Love every "inch" of it.
 
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Old Jan 31, 2015 | 02:08 PM
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Originally Posted by 98hotrodfatboy
When boring an 88" to 98" do you have to bore the case as well or is it just the max you can do to the jugs without touching the cases?
No to case bore; yes to max bore without case boring.
 
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Old Jan 31, 2015 | 02:19 PM
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Default Thanx
I am trying to learn a little about the twinkies incase some day that I might own one, Thanx...
 
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Old Jan 31, 2015 | 03:36 PM
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no case boring for the 3.937 bore (98" off a 88" and 107" off a 96")
 
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Old Jan 31, 2015 | 11:57 PM
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So I can bore the jugs to a 98 and what size Pistons do I need to get?
 
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Old Feb 1, 2015 | 06:20 AM
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we use either wiseco or CP.you can get the pistons from either.just make sure who ever is doing the boring has the right equipment & knowledge.having the cylinder perfectly centered & straight is VERY important when doing the 3.937" bores
 
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