BSF Fasteners

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BSF (British Standard Fine) is a fine-pitch alternative to British Standard Whitworth (BSW) thread. It was used for steel bolts and nuts on much of Britain's motorcycle industry, prior to adoption of Unified standards. Used extensively on pre-WWII BSA and other brands, where Triumph and Norton tended more towards the use of the finer threaded CEI (Cycle Thread) fasteners.

21-5662 Bolt

Diameter ⌀: 5/16 inch
Length UH: 5/8 inch
Thread Form: BSF 22tpi
Head: Tallish
Spanner Size: 1/4W 5/16BS
Finish: Plated

NZ$ 6.60
NZ$ 5.95
21-5669 Bolt

Diameter ⌀: 5/16 inch
Length UH: 1&1/2 inch
Thread Form: BSF 22tpi
Spanner Size: 1/4W 5/16BS
aka: S5669

NZ$ 2.15
NZ$ 1.90

Out Of Stock
21-5687 Bolt

Diameter ⌀: 5/16 inch
Length UH: 6 inch
Thread Form: BSF 22tpi
Head: Standard
Spanner Size: 1/4W 5/16BS
Finish: Plated

NZ$ 5.35
NZ$ 4.80
21-5712 Bolt

Diameter ⌀: 3/8 inch
Length UH: 3/4 inch
Thread Form: BSF 20tpi
Head: Standard
Spanner Size: 5/16W 3/8BS
Finish: Plated

NZ$ 2.70
NZ$ 2.45
21-5713 Bolt

Diameter ⌀: 3/8 inch
Length UH: 7/8 inch
Thread Form: BSF 20tpi
Head: Standard
Spanner Size: 5/16W 3/8BS
Finish: Plated

NZ$ 3.20
NZ$ 2.90
21-5727 Bolt

Diameter ⌀: 3/8 inch
Length UH: 2&1/4 inch
Thread Form: BSF 20tpi
Head: Standard
Spanner Size: 5/16W 3/8BS
Finish: Plated

NZ$ 4.85
NZ$ 4.35
57-1778 Bolt

Diameter ⌀: 5/16 inch
Length UH: 1&1/8 inch
Thread Form: BSF 22tpi
Head: Small Hex
Spanner Size: 3/16W 1/4BS

NZ$ 2.85
NZ$ 2.55
57-1779 Screw

Diameter ⌀: 5/16 inch
Length UH: 1&3/4 inch
Thread Form: BSF 22tpi
Head: Allen Cap
aka: T1779

NZ$ 6.35
NZ$ 5.70
68-0013 Stud

Crankcase Stud
BSA
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 1&1/2 inch

NZ$ 2.70
NZ$ 2.45
68-0033 Stud

Stator Mounting Stud
BSA A50 A65
End 1: 1/4 CEI/BSF 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 3&5/8 inch

NZ$ 24.15
NZ$ 21.75

Out Of Stock
68-0036 Stud

Stator Mounting Stud
BSA a50 & A65 models
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 3&1/4 inch

NZ$ 8.05
NZ$ 7.25
68-0066 Stud

Manifold Stud
BSA
End 1: 1/4 CEI/BSF 26tpi
End 2: 1/4 CEI/BSF 26tpi
Overall Length: 2&5/8 inch

NZ$ 2.70
NZ$ 2.45
68-0067 Stud

Manifold Stud
BSA
End 1: 1/4 CEI/BSF 26tpi
End 2: 1/4 CEI/BSF 26tpi
Overall Length: 2 inch

NZ$ 1.60
NZ$ 1.45
68-0081 Stud

Cylinder Head Stud
BSA A50 & A65 models
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 3&1/4 inch

NZ$ 5.35
NZ$ 4.80
68-0087 Stud

Rocker Cover Stud
BSA A50 & A65
End 1: 1/4 CEI/BSF 26tpi
End 2: 1/4 CEI/BSF 26tpi
Overall Length: 29/32 inch
aka: 76-0013

NZ$ 1.60
NZ$ 1.45
68-0222 Stud

Manifold Stud
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 1&1/4 inch

NZ$ 10.75
NZ$ 9.65
68-0237 Nut

Adjuster Nut
Thread: BSF 7/16 inch 18tpi
Spanner Size: 3/8W 7/16BS
Height: Thin
Style: 1 flat side
aka: NM23384

NZ$ 2.70
NZ$ 2.45
68-0272 Bolt

Oil Union Bolt
Diameter ⌀: 5/16 inch
Length UH: 3/4 inch
Thread Form: BSF 22tpi
Spanner Size: 1/4W 5/16BS
BSA A50 & A65 models

NZ$ 3.20
NZ$ 2.90

Out Of Stock
68-0531 Stud

Locating Stud
Cylinder Barrel
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 1&7/16 inch
BSA A50 & A65 models

NZ$ 8.05
NZ$ 7.25
68-0605 Screw

Fork Drain Screw
Diameter ⌀: 1/4 inch
Length UH: 5/16 inch
Thread Form: CEI BSF 26tpi
Head Style: Slotted Button
BSA A50 & A65 models

NZ$ 1.60
NZ$ 1.45
68-0876 Stud

Rocker Cover Stud
End 1: 1/4 CEI BSF 26tpi
End 2: 1/4 CEI BSF 26tpi
Overall Length: 1&1/2 inch
BSA A50 & A65 models

NZ$ 2.15
NZ$ 1.90
68-0952 Stud

Stepped Stud
Cylinder Locating
BSA A50 & A65 models
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 1&7/16 inch

NZ$ 10.75
NZ$ 9.65
68-3060 Stud

Gearbox Cover Stud
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 1&1/4 inch
BSA A50 & A65 models

NZ$ 3.20
NZ$ 2.90
68-4568 Nut

Thumb Nut
Battery Box
Thread: CEI BSF 1/4 inch 26tpi
BSA A50 & A65 models

NZ$ 5.35
NZ$ 4.80

Out Of Stock
70-3799 Bolt

Crankcase Bolt
Triumph Unit 350 500
Diameter ⌀: 5/16 inch
Length UH: 1&5/8 inch
Thread Form: BSF 22tpi
aka: E3799

NZ$ 3.75
NZ$ 3.40

Out Of Stock
70-3803 Stud

Crankcase Stud
Triumph Unit 350 500
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 3&3/4 inch
aka: E3803

NZ$ 6.05
NZ$ 5.45
70-3819 Stud

Cylinder Base Stud
End 1: 3/8 CEI 26tpi
End 2: 3/8 BSF 20tpi
Overall Length: 1&3/4 inch
Triumph Unit 350 500
aka: E3819

NZ$ 5.35
NZ$ 4.80
70-3820 Stud

Cylinder Base Stud
End 1: 3/8 CEI 26tpi
End 2: 3/8 BSF 20tpi
Overall Length: 1&1/2 inch
Triumph Unit 350 500
aka: E3820

NZ$ 4.05
NZ$ 3.60
70-3880 Stud

Inlet Manifold Stud
Triumph Unit 350 500
End 1: 5/16 CEI/BSF 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 1&1/4 inch
aka: E3880

NZ$ 4.85
NZ$ 4.35
70-3980 Stud

Alternator Stator Stud
Triumph Pre Unit
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 1&13/16 inch
aka: E3980

NZ$ 4.30
NZ$ 3.90

Out Of Stock
70-4098 Bolt

Crankcase Bolt
Diameter ⌀: 5/16 inch
Length UH: 1&7/8 inch
Thread Form: BSF 22tpi
aka: E4098

NZ$ 7.20
NZ$ 6.45
70-4123 Stud

Alternator Stator Stud
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 1&7/16 inch
aka: E4123

NZ$ 5.15
NZ$ 4.65
70-4145 Stud

Alternator Stud
Triumph Unit 650
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 3&9/16 inch
aka: E4145

NZ$ 5.35
NZ$ 4.80
70-4154 Plug

Primary Drain Plug
Triumph Unit 350 500
Diameter ⌀: 7/16 inch
Length UH: 7/16 inch
Thread Form: BSF 18tpi
aka: E4154

NZ$ 4.50
NZ$ 4.05
70-4491 Stud

STUD
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 1&5/8 inch
aka: E4491

NZ$ 5.35
NZ$ 4.80
70-4532 Bolt

Bolt
Diameter ⌀: 5/16 inch
Length UH: 1&5/16 inch
Thread Form: BSF 22tpi
Head: Small Hex
aka: E4532

NZ$ 5.35
NZ$ 4.80
70-4535 Stud

Gearbox Stud
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 3 inch
aka: E4535

NZ$ 5.35
NZ$ 4.80
70-4536 Stud

Long Stator Stud
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 4&1/4 inch
aka: E4536

NZ$ 30.20
NZ$ 27.15
70-4537 Stud

Short Stator Stud
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 3&1/4 inch
aka: E4537

NZ$ 13.40
NZ$ 12.10
70-4539 Plug

Oilway Plug
Diameter ⌀: 5/16 inch
Length UH: 5/16 inch
Thread Form: BSF 22tpi
aka: E4539

NZ$ 3.75
NZ$ 3.40
70-4540 Bolt

Crankcase Bolt
Diameter ⌀: 5/16 inch
Length UH: 1&3/4 inch
Thread Form: BSF 22tpi
aka: E4540

NZ$ 11.05
NZ$ 9.95
70-4541 Bolt

Crankcase Bolt
Diameter ⌀: 5/16 inch
Length UH: 2&1/2 inch
Thread Form: BSF 22tpi
aka: E4541

NZ$ 13.00
NZ$ 11.70
70-4542 Stud

Crankcase Stud
End 1: 3/8 CEI 26tpi
End 2: 3/8 BSF 20tpi
Overall Length: 4&5/8 inch
aka: E4542

NZ$ 7.50
NZ$ 6.75
70-4706 Plug

Tacho Drive Plug
Thread: BSF 1/2 inch 16tpi
aka: E4706

NZ$ 7.10
NZ$ 6.35
70-4806 Screw

Case Screw
Diameter ⌀: 5/16 inch
Length UH: 29/32 inch
Thread Form: BSF 22tpi
Head Style: Fillister Posidriv
aka: E4806

NZ$ 2.70
NZ$ 2.45
70-4922 Plug

Drain Plug
Primary Chain Adjuster
Diameter ⌀: 7/16 inch
Thread Form: BSF 18tpi
aka: E4922

NZ$ 9.05
NZ$ 8.15
70-6929 Bolt

Crankcase Bolt
Diameter ⌀: 3/8 inch
Length UH: 4 inch
Thread Form: BSF 20tpi
aka: E6929

NZ$ 9.30
NZ$ 8.40
70-7885 Bolt

Sealing Plug Bolt
Diameter ⌀: 5/16 inch
Length UH: 3/8 inch
Thread Form: BSF 22tpi
aka: E7885

NZ$ 1.60
NZ$ 1.45
70-8008 Stud

Crankcase Stud
BSA Triumph Singles
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 2&3/4 inch
aka: E8008

NZ$ 8.05
NZ$ 7.25
70-8013 Stud

Oil Junction Stud
End 1: 5/16 CEI 26tpi
End 2: 5/16 BSF 22tpi
Overall Length: 1&7/8 inch
aka: E8013

NZ$ 6.45
NZ$ 5.80

BSF Fasteners

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