Twin cam, 88 1450, bore 3.750 strock 4.000
Bath tub shaped ccombustion chambers
3.7500 X 3.750 = 14.06 X 4.000 = 56.24 X .7854 = 44.17
X 2 =88.34 88.34 X 16.39 = 1447.89
1447
÷
2 = 723 + 85 Lcc head area +
11 Lcc head gasket
area + 4
Lcc piston value pockets and piston- cylinder
ring area
and piston not flat with cylinder top.
1447 ÷
2 = 723 + 100 Lcc = 823 ÷ 100 = 8.23 to 1
Harley manuel
specification is 9-1 standard.
If necessary
deck head .010 at a time and recheck Lcc.
Have value
job done before necessary checking.
The grinding
of value and seats can add 1-2 Lcc to formula.
Engine at
different rpm will strech rod and pistons .040,
if it happens
it will just go into head gasket area.
Average
1450 & 1550 stock gasket is .055 to .060 thick.
Installed
head gasket is a little less .005 to .010.
Install
HD adjustable pushrods and cover kit it will make the job easyier,
and all
lifter will have the same preload.
Install
S&S HL2T spacer in hydraulic lifter, spacers will stop lifter
bleed down
at high rpm and engine starting up easyier.
Always use
oil marked motorcycle oil.
TWIN CAM
Twin cam 95 1550 bore 3.875 strock 4.000
3.875 X 3.875 =15.02 15.02 X 4.000 =60.08 60.08 X .7854
=47.19 X 2 =94.38, 94.38 X 16.39 = 1546.89
1546.89 ÷ 2 = 773.45 + 100Lcc ÷ 100 = 8.73-1
98Lcc ÷ 98 = 8.89-1
96Lcc ÷ 96 = 9.06-1