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Discussion Starter #1
I have this plan to build a 107" motor using the stock 4" stroke and 4-1/8" bore and am wondering if it's possible to use the SE 4.060 cylinders and bore them to 4.125". Does anyone know if they have enough metal in the liner to do this? Or do I need to look at S&S or Axtell or somebody's cylinders? Not that I'm in a hurry; this will be next winter's project, assuming I have the $$ in order for it.
 

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I have talked to Randy at Hyperformance about this before, and he said he wouldnt bore them that far. I went with S&S.
 

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.015 over is the max,I built a 104 with 4.075 bore x 4" stroke using the HD cylinders,It ended up being a very good combo:)
 

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you can use the SE clys to do a 104 all bore. custom pistons. from Randy at hyperperformance or from axtell. both have the SE clys also.
but if you want to go 107 then look at Axtell or S&S

OOPS DURWOOD covered the 104
 

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Been some talk of doing this and believe it or not you would actually end up with a thicker spigot than a stock cylinder over bored for a 98, I have a set in my shop and will have to see how the liner compares to a stock cylinder, the problem as I see it would be that the cylinders are relieved for the piston oilers and for spigot to spigot clearance at the middle, this leaves a thin area of the spigot between the two that would kind of just be hanging there.
You could be the one to break new ground on this if you try but I hardly feel it is worth the risk.
S&S should be shipping their new 4.125 cylinders with a close to stock appearance any time now, maybe already doing it. Those all bore motors are really nice.
 

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Discussion Starter #6
Thanks, all for the responses. Doesn't sound all that promising; I want to make sure the spigots are strong enough and that there's enough meat for the cylinders to be servicable. I guess I'll be looking at S&S or Axtell. I have plenty of time, but I like to have a clear idea what I'm going to do in advance and then collect parts as funds allow. This is going to be a next winter project, but I'm sure looking forward to it!
 

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Keep in mind also that the S&S or Axtell cylinders aren't done a 4.125" either. Meaning there's more there if you need/want to over-bore those as well.


K.
 

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Keep in mind also that the S&S or Axtell cylinders aren't done a 4.125" either. Meaning there's more there if you need/want to over-bore those as well.


K.
o yeah 114 all bore. now were talking :woohoo:
 

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I do have 4.080" pistons available now.
Sounds like a good alternative as well, the difference of the 4.125 bore to the 4.080 bore is only 2.32, hardly worth nearly double the cost of cylinders and pistons not to mention the Harley cylinders have been VERY reliable and the extra spigot length is definitely a plus.
 

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Discussion Starter #11
That is an interesting option. I was really liking the 4.125" bore, as forged, coated skirt KB 4.125 pistons can be had for $165 shipped; I thought if I can get into a pair of the SE cylinders and bore to fit I'm well on my way to a low-buck all-bore 107". I may take a good look at the 4.080 idea.
 

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That is an interesting option. I was really liking the 4.125" bore, as forged, coated skirt KB 4.125 pistons can be had for $165 shipped; I thought if I can get into a pair of the SE cylinders and bore to fit I'm well on my way to a low-buck all-bore 107". I may take a good look at the 4.080 idea.
Who sells these pistons?
 

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Discussion Starter #14 (Edited)
Who sells the KB 4.125 pistons? RPM Machine in Utah. 877-354-3812. No affiliation whatsoever, just stumbled across them while looking for reasonably priced pistons.

The KB part numbers for these are:

9.5:1 (9.4cc dish) KB910C
10.0:1 (3.6cc dish) KB911C
10.5:1 (1.5cc dome) KB912C

All the above assume 85cc heads.

I've gotten a set of 95" pistons from them already, come with everything you'd expect to get.
 

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If you are going to buy cylinders, I would not consider anything but S&S or Harley!! Just saying.
 

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I would tend to agree with that. R&R too maybe? -Tutt
 

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Discussion Starter #18
I spoke to S&S today and they tell me they don't have an off the shelf cylinder that will work, but can "special order" a pair. The guy gave me a special order part number and a suggested retail price; all I gotta do is have an S&S dealer order the cylinders and in 5 days or so they'l be ready. Not bad! And the price is reasonable as well. More than the retail price of the SE cylinders but far better than I expected. When I get some $$ together this is the route I'll take, for sure.
 

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I spoke to S&S today and they tell me they don't have an off the shelf cylinder that will work, but can "special order" a pair. The guy gave me a special order part number and a suggested retail price; all I gotta do is have an S&S dealer order the cylinders and in 5 days or so they'l be ready. Not bad! And the price is reasonable as well. More than the retail price of the SE cylinders but far better than I expected. When I get some $$ together this is the route I'll take, for sure.
I didnt think they had that cly.
so that means a custom piston from S&S as well?
think I would just stay with a tried and true all bore 107 myself.
 

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Discussion Starter #20
No, not custom pistons. KB has an off the shelf 4.125 bore piston for the '99-'06, 4" stroke TC88. So I'd use this piston and the S&S cylinder with a 4.125" bore and stock length.

Larry, you say yu'd use a tried and true all-bore 107"... is there a tried and true 107" setup for the 4" stroke motor? I know there is for the later 4-3/8" stroke TC96 but haven't heard of any such thing for the earlier motors.

I'm really liking this idea... somebody talk me out of it if you think I'm insane, but I can't really see a good reason not to do it. Not that I'm in a hurry, mind you; like I said, this will be next winter's project. But I like to start lining my ducks up way ahead...
 
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