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Technical Forums => Twin Cam => Topic started by: aharp on May 14, 2020, 07:47:52 AM

Title: SE120 piston compression height
Post by: aharp on May 14, 2020, 07:47:52 AM
Anyone have this figure?
Title: Re: SE120 piston compression height
Post by: Ohio HD on May 14, 2020, 08:00:37 AM
120r 4.062 x 4.625 - 0.906"  0.960" 1.050"
Title: Re: SE120 piston compression height
Post by: Ohio HD on May 14, 2020, 08:11:54 AM
Bore Inch: 4.060
Comp. Ht. IN: .960  1.050"
Cylinders: V2
Eng. Disp Liters: 1966.0
Eng. Disp. IN.: 120
Ex Val Depth/Dia: .180/1.846
Int Val Depth/Dia: .221/2.230
OE Deck Height: 6.000
Title: Re: SE120 piston compression height
Post by: aharp on May 14, 2020, 08:19:10 AM
Quote from: Ohio HD on May 14, 2020, 08:11:54 AM
Bore Inch: 4.060
Comp. Ht. IN: .960
Cylinders: V2
Eng. Disp Liters: 1966.0
Eng. Disp. IN.: 120
Ex Val Depth/Dia: .180/1.846
Int Val Depth/Dia: .221/2.230
OE Deck Height: 6.000

Thanks. Havent had to think outside the box for a while lol. In the first reply the 4.062 is that bore? Cylinders are 4.92 I measured
Title: Re: SE120 piston compression height
Post by: Ohio HD on May 14, 2020, 09:33:49 AM
Quote from: aharp on May 14, 2020, 08:19:10 AM
Quote from: Ohio HD on May 14, 2020, 08:11:54 AM
Bore Inch: 4.060
Comp. Ht. IN: .960 1.050"
Cylinders: V2
Eng. Disp Liters: 1966.0
Eng. Disp. IN.: 120
Ex Val Depth/Dia: .180/1.846
Int Val Depth/Dia: .221/2.230
OE Deck Height: 6.000

Thanks. Havent had to think outside the box for a while lol. In the first reply the 4.062 is that bore? Cylinders are 4.92 I measured

Standard bore is 4.062". I thought that maximum was something like 4.125"?

And I thought that is risky.
Title: Re: SE120 piston compression height
Post by: Don D on May 14, 2020, 09:55:57 AM
The shorter rods, -.112, stock cylinder height.
Title: Re: SE120 piston compression height
Post by: Ohio HD on May 14, 2020, 10:31:18 AM
Quote from: Ohio HD on May 14, 2020, 08:11:54 AM
Bore Inch: 4.060
Comp. Ht. IN: .960 1.050"
Cylinders: V2
Eng. Disp Liters: 1966.0
Eng. Disp. IN.: 120
Ex Val Depth/Dia: .180/1.846
Int Val Depth/Dia: .221/2.230
OE Deck Height: 6.000

I went by this KB info, but it doesn't add up.
https://uempistons.com/series-3809-kb-v-twin-super-duty-harley-davidson-120-1966-kb715lca.html


1.050" height come back as good with my calculator.

[attach=0,msg1346890]
Title: Re: SE120 piston compression height
Post by: Don D on May 14, 2020, 10:49:19 AM
Bingo.
UEM has a .960 124 piston dished.  Nothing I use
Title: Re: SE120 piston compression height
Post by: Ohio HD on May 14, 2020, 04:19:29 PM
Quote from: aharp on May 14, 2020, 08:19:10 AM
Quote from: Ohio HD on May 14, 2020, 08:11:54 AM
Bore Inch: 4.060
Comp. Ht. IN: .960 1.050"
Cylinders: V2
Eng. Disp Liters: 1966.0
Eng. Disp. IN.: 120
Ex Val Depth/Dia: .180/1.846
Int Val Depth/Dia: .221/2.230
OE Deck Height: 6.000

Thanks. Havent had to think outside the box for a while lol. In the first reply the 4.062 is that bore? Cylinders are 4.92 I measured

Aaron, I got home and looked in my verified info     :embarrassed:

1.050" is what CP lists and is correct. Sorry for the detoured info.


[attach=0,msg1346936]


Title: Re: SE120 piston compression height
Post by: TorQuePimp on May 14, 2020, 07:13:56 PM
Quote from: HD Street Performance on May 14, 2020, 10:49:19 AM
Bingo.
UEM has a .960 124 piston dished.  Nothing I use

Those pistons I cannot figure out why they exist
Title: Re: SE120 piston compression height
Post by: aharp on May 15, 2020, 02:39:23 AM
Quote from: Ohio HD on May 14, 2020, 04:19:29 PM

Aaron, I got home and looked in my verified info     :embarrassed:

1.050" is what CP lists and is correct. Sorry for the detoured info.


[attach=0,msg1346936]
No sweat at all my friend. Thanks for the help