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Old 12-29-2017, 05:02 PM
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Default Bore size

More confusion :71 shovel
Manual states 3 7/16 bore but I can only find rings for a 3 5/8 What am I missing?
I'm showing 3.430 bore Thanks for info to set me straight
 
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Old 12-29-2017, 06:04 PM
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first your numbers are incorrect - stock bore is 3.4375 you number is .0075 smaller then that

you want moly rings not full cast -- measure the piston bottom about an inch up between and below the rist pin not 180 from it
 
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Old 12-29-2017, 07:25 PM
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I was hoping you would chime in , so thank you .
What about bore size of 3 5/8 ? Seems to be the only ones I ca find and also seem very popular. Is that an 80 in. ?
Hope you don't mind but in my head I keep calling you Joisy John. Must be from something in my past.
 
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Old 12-29-2017, 08:51 PM
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74 inch motor - 3-7/16 bore 3 -31 /32 stroke

80 inch motor -3 -1/2 bore 4-1/4 stroke

3-5/8 bore requires an over size engine block as the cylinders do not just slide in - but the 74 and the 80 use the same block, as the bore on the 80 inch is a .060 over piston bore in a 74 cylinder, but the rods have a different length so it all goes

if you clean the top of your piston carefully, it will have the over bore size on it, and I can give you the correct hastings ring set numbers to get
 
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Old 12-30-2017, 06:05 AM
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John , you are the man. Thank You. Top of piston has a zero . I believe it should all be stock as its under 10k miles. Must have loaned out all of my stuff over the years and it didn't come back. Ridge reamer ( although there isn't a ridge) cyl. hone , but do have the ring compressor. I was in automotive for many years but haven't done a Harley since my '47 Knuck. I really do appreciate all your help.
 
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Old 12-30-2017, 07:24 AM
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I like Jerzey John, but that's just me.

Good luck with your project.
 
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Old 12-31-2017, 09:27 AM
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the hastings ring series number is as follows -- 2M6482 < then it will be marked std - .005 - .010 kind of thing

v twin catalog on line as a guest -- # 11-1368 is what you want
 
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Old 01-01-2018, 01:18 PM
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Thank you John, I ordered through my local indie. I do have the V Twin catalog. Its been almost as useful as you have been.
 
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