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Main bolt

The main bolt holds the primary cover.

34957-52


Sportster_Engine_Primary_Primary-cover_34957-52_main-bolt_1952-1956 Sportster_Engine_Primary_Primary-cover_34957-52_main-bolt_1952-1956_Colony CAD
Blueprint
The main bolt in the K-model installs in the middle of the primary cover. It secures to a threaded boss in the primary cover. Problems: Straight slots get torn up by screwdrivers. Image credit: Jan Willem Boon - parts for your Harley-Davidson - database.

34957-57

Sportster_Engine_Primary_Primary-cover_34957-57_main-bolt_1957-1966 Sportster_Engine_Primary_Primary-cover_34957-57_main-bolt_1957-1966_Colony
The main bolt used on the Sportster is longer since the primary cover is deeper. This is because the clutch in the Sportster uses more plates and is deeper as well. Image credit: Jan Willem Boon - parts for your Harley-Davidson - database.

1369

Sportster_Engine_Primary_Primary-cover_1369_main-bolt_1958-1969 Sportster_Engine_Primary_Primary-cover_1369_main-bolt_1958-1969_Colony
Bolt, 1/4"-20 x 11/16" fillister head. The steel primary takes these screws. Problems: Straight slots get torn up by screwdrivers. Image credit: Jan Willem Boon - parts for your Harley-Davidson - database.

2350W

Sportster_Engine_Primary_Primary-cover_2350W_main-bolt_1967-1970 Sportster_Engine_Primary_Primary-cover_2350W_main-bolt_1967-1970
Bolt, 1/4"-20 x 1 3/4" countersunk head. Problems: Straight slots get torn up by screwdrivers. Image credit: Jan Willem Boon - parts for your Harley-Davidson - database.

2351W

Sportster_Engine_Primary_Primary-cover_2351W_main-bolt_1971-1976 Sportster_Engine_Primary_Primary-cover_2351W_main-bolt_1971-1976
Bolt, 1/4"-20 x 2" Phillips head/ Pozidriv fillister head. Problems: Pozidriv not real mate for Phillips head. Image credit: Jan Willem Boon - parts for your Harley-Davidson - database.

1370W

Sportster_Engine_Primary_Primary-cover_1370W_main-bolt_1977-1978 Sportster_Engine_Primary_Primary-cover_1370W_main-bolt_1977-1978
Bolt, 1/4-20 x 2-1/4 Phillips fillister head. Problems: I can't find a real picture of this bolt.

1381

Sportster_Engine_Primary_Primary-cover_1381_main-bolt_1979-1980 Sportster_Engine_Primary_Primary-cover_1381_main-bolt_1979-1980
Bolt, 1/4"-20 x 2 1/2" Pozidriv fill. head. Problems: Pozidriv not real mate for Phillips head.Image credit: Jan Willem Boon - parts for your Harley-Davidson - database.

914

Sportster_Engine_Primary_Primary-cover_914_main-bolt_1979-1980 Sportster_Engine_Primary_Primary-cover_914_main-bolt_1979-1980
 Bolt, 1/4"-20 x 2 1/4" Pozidriv head. Problems: Pozidriv not real mate for Phillips head.Image credit: Jan Willem Boon - parts for your Harley-Davidson - database.

3479

Sportster_Engine_Primary_Primary-cover_3479_main-bolt_1981-1984 Sportster_Engine_Primary_Primary-cover_3479_main-bolt_1981-1984
Bolt, 1/4"-20 x 2 1/4" socket head.Image credit: Jan Willem Boon - parts for your Harley-Davidson - database.