| Year/Type/part
number: |
|
|
Running
clearances: |
|
|
|
|
| 1954
R cams |
intake
opens |
37d. BTC
|
.006 clearance |
| (25
499-53R) |
intake
closes |
64d. ABC |
|
| .395
lift |
exhaust opens |
60d. BBC |
.008 clearance |
|
exhaust closes |
37d. ATC
|
cold engine |
|
|
|
|
| 1956
R cams |
intake opens |
55d. BTC
|
.006 clearance |
| (25
499-55R) |
intake closes |
72d. ABC |
|
| .395
lift |
exhaust opens |
62d. BBC |
.008 clearance |
|
exhaust closes |
48d. ATC
|
cold engine |
|
|
|
|
| 1959
A cams |
intake opens |
80d. BTC
|
.006 clearance |
| (25
499-59R) |
intake closes |
66d. ABC |
|
| .395
lift |
exhaust opens |
60d. BBC |
.008 clearance |
|
exhaust closes |
42d. ATC
|
cold engine |
|
|
|
|
| 1961
C cams |
front intake opens |
80d. BTC |
.006 clearance |
| (25
499-61R) |
rear intake opens |
75d. BTC |
|
| .395
lift |
exhaust opens |
60d. BBC |
.008 clearance |
|
exhaust closes |
42d. ATC |
cold engine |
|
|
|
|
| 1962
E cams |
intake opens |
70d. BTC |
.006 clearance |
| (25
499-62R) |
intake closes |
66d. ATC |
|
| .395
lift |
exhaust opens |
56d. BBC |
.008 clearance |
|
exhaust closes |
42d. ATC |
cold engine |
|
|
|
|
| 1964
F cams |
intake opens |
70d. BTC
|
.006 clearance |
| (25
499-64R) |
intake closes |
66d. ABC |
|
| .420
lift |
exhaust opens |
58d. BBC |
.008 clearance |
|
exhaust closes |
42d. ATC
|
cold engine |
|
|
|
|
| 1967
J cams |
intake opens |
66d. BTC
|
.006 clearance |
| (25
499-67R) |
intake closes |
66d. ABC |
|
| .395
lift |
exhaust opens |
65d. BBC |
.010 clearance |
|
exhaust closes |
40d. ATC
|
cold engine |
|
|
|
|
| 1966
H cams |
intake opens |
66d. BTC
|
.006 clearance |
| (25
499-66R) |
intake closes |
66d. ABC |
|
| int.
.446 lift |
exhaust opens |
58d. BBC |
.010 clearance |
| exh.
.415 lift |
exhaust closes |
42d. ATC
|
cold engine |
|
|
|
|
| 1969
J & K cams |
intake opens |
66d. BTC
|
.006 clearance |
| (25
499-69R) |
intake closes |
66d. ABC |
|
| .395
lift |
exhaust opens |
58d. BBC |
.010 clearance |
|
exhaust closes |
42d. ATC
|
cold engine |
|
|
|
|
| 1969
J & L cams |
intake opens |
66d. BTC
|
.006 clearance |
| (25
498-69R) |
intake closes |
66d. ABC |
|
| .395
lift |
exhaust opens |
65d. BBC |
.010 clearance |
|
exhaust closes |
40d. ATC
|
cold engine |
|
|
|
|
| Head
Clearances: with valves fully opened: |
| Intake |
.110 |
|
|
| Exhaust |
.040 |
|
|
|
|
|
|
| Cam
timing:
check at .010 lift with no tappet clearance |
|
| Cams
tolerances: most were made with plus or minus 2 degrees
tolerance |
|
| Shim
valve springs within .080 to .090 of being coil bound |
|
|
|
|
| spring
pressures: |
inner |
81lbs @ .86" |
|
|
outer |
126 lbs @ .94" |
|
Thanks to Jim Haubert for most of
the info on this
page, from original H-D racing spec sheet |
