Transmission 4-speed Parts

243 products

Transmission 4-Speed Parts for Harley-Davidson supply the gears, shafts, bearings and internal components needed to rebuild or upgrade the classic four-speed gearbox found in Big Twin and 45-inch Flathead models from 1935 through to 1986. Available from Iron City Motorcycles, an authorised Harley-Davidson dealer in Leeds, these parts cover everything from Knucklehead and Panhead Servi-Cars to Shovelhead FL and FX machines. MCS and Samwel lead the range with OEM-specification replacements and hard-to-find vintage components. A smooth-shifting four-speed transmission is central to the riding experience on these classic Harleys, and sourcing the correct internal parts is the first step toward a reliable rebuild. Browse the full range below.

OEM Replacement Parts OEM Only — Active Genuine H-D & replacements Tap to clear filter

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Showing 1–48 of 243 Transmission|TRANSMISSION/DRIVELINE

V-Twin ROTARY TOP ASSEMBLIES FOR 4-SPEED BIG TWIN

ROTARY TOP ASSEMBLIES FOR 4-SPEED BIG TWIN

V-Twin

#781053

£1731.89£1558.70

Member£1472.11-15%

V-Twin COMPLETE 4-SPEED BIG TWIN RATCHET TOPS

COMPLETE 4-SPEED BIG TWIN RATCHET TOPS

V-Twin

#768020

£808.09£727.28

Member£686.88-15%

V-Twin 4 SPEED BIG TWIN TRANSMISSION CASES

4 SPEED BIG TWIN TRANSMISSION CASES

V-Twin

#781047

£703.87£633.48

Member£598.29-15%

V-Twin COMPLETE 4-SPEED BIG TWIN RATCHET TOPS

COMPLETE 4-SPEED BIG TWIN RATCHET TOPS

V-Twin

#768018

£669.13£602.22

Member£568.76-15%

V-Twin COMPLETE 4-SPEED BIG TWIN RATCHET TOPS

COMPLETE 4-SPEED BIG TWIN RATCHET TOPS

V-Twin

#768021

£661.16£595.04

Member£561.99-15%

V-Twin Hand Shifter Jockey Top, BT37-54

Hand Shifter Jockey Top, BT37-54

V-Twin

#789823

£563.22£506.90

Member£478.74-15%

V-Twin 4 SPEED BIG TWIN TRANSMISSION CASES

4 SPEED BIG TWIN TRANSMISSION CASES

V-Twin

#781046

£540.43£486.39

Member£459.37-15%

Jims JIMS 4 SPEED TRANSMISSION REBUILD KITS

JIMS 4 SPEED TRANSMISSION REBUILD KITS

Jims

#237344

£530.16£477.14

Member£450.64-15%

Jims JIMS 4 SPEED TRANSMISSION REBUILD KITS

JIMS 4 SPEED TRANSMISSION REBUILD KITS

Jims

#235888

£326.34£293.71

Member£277.39-15%

V-Twin Ratchet Top Shifter Cam, FX76-79

Ratchet Top Shifter Cam, FX76-79

V-Twin

#768002

£295.00£265.50

Member£250.75-15%

Andrews ANDREWS 4 SPEED TRANSMISSION MAIN SHAFTS

ANDREWS 4 SPEED TRANSMISSION MAIN SHAFTS

Andrews

#237150

£288.22£259.40

Member£244.99-15%

Andrews ANDREWS 4 SPEED TRANSMISSION MAIN SHAFTS

ANDREWS 4 SPEED TRANSMISSION MAIN SHAFTS

Andrews

#234726

£276.44£248.80

Member£234.97-15%

Eastern MC Parts Countershaft Gear, 15x17, 69-76 (#35700-69)

Countershaft Gear, 15x17, 69-76 (#35700-69)

Eastern MC Parts

#231590

£274.82£247.34

Member£233.60-15%

Andrews ANDREWS 4 SPEED TRANSMISSION MAIN SHAFTS

ANDREWS 4 SPEED TRANSMISSION MAIN SHAFTS

Andrews

#234728

£274.30£246.87

Member£233.16-15%

Eastern MC Parts Main Drive Gear, 26T 4-Speed 38-77 (#35065-65B)

Main Drive Gear, 26T 4-Speed 38-77 (#35065-65B)

Eastern MC Parts

#231530

£258.32£232.49

Member£219.57-15%

Andrews ANDREW STOCK MAIN DRIVE GEARS

ANDREW STOCK MAIN DRIVE GEARS

Andrews

#234717

£214.00£192.60

Member£181.90-15%

V-Twin Countershaft 3rd & 4th Cluster Gear

Countershaft 3rd & 4th Cluster Gear

V-Twin

#731708

£212.99£191.69

Member£181.04-15%

Andrews ANDREW STOCK MAIN DRIVE GEARS

ANDREW STOCK MAIN DRIVE GEARS

Andrews

#234718

£212.65£191.39

Member£180.75-15%

Eastern MC Parts Countershaft 3rd & 4th Cluster Gear

Countershaft 3rd & 4th Cluster Gear

Eastern MC Parts

#731706

£206.08£185.47

Member£175.17-15%

MCS Clutch gear, transmission. 14t

Clutch gear, transmission. 14t

MCS

#971277

£199.51£179.56

Member£169.58-15%

V-Twin Countershaft 3rd & 4th Cluster Gear

Countershaft 3rd & 4th Cluster Gear

V-Twin

#731707

£189.07£170.16

Member£160.71-15%

Andrews ANDREWS 1ST GEAR SETS FOR 4 SPEED TRANSMISSIONS

ANDREWS 1ST GEAR SETS FOR 4 SPEED TRANSMISSIONS

Andrews

#234710

£184.99£166.49

Member£157.24-15%

Andrews ANDREWS STOCK 3RD GEAR (1.23 RATIO)

ANDREWS STOCK 3RD GEAR (1.23 RATIO)

Andrews

#234715

£184.06£165.65

Member£156.45-15%

Andrews ANDREWS 1ST GEAR SETS FOR 4 SPEED TRANSMISSIONS

ANDREWS 1ST GEAR SETS FOR 4 SPEED TRANSMISSIONS

Andrews

#234709

£183.74£165.37

Member£156.18-15%

V-Twin Hand Shifter Shift Drum Jockey Top

Hand Shifter Shift Drum Jockey Top

V-Twin

#789928

£182.23£164.01

Member£154.90-15%

Eastern MC Parts M1+M2 Cluster Gear, BT59-84

M1+M2 Cluster Gear, BT59-84

Eastern MC Parts

#231581

£162.08£145.87

Member£137.77-15%

Eastern MC Parts 1952-1979 FOOT SHIFT RATCHET TOP

1952-1979 FOOT SHIFT RATCHET TOP

Eastern MC Parts

#232778

£148.33£133.50

Member£126.08-15%

Zodiac (Genuine Zodiac Products) GZP Main Drive Gear, 26T 4-Speed 77-86 (#35067)

GZP Main Drive Gear, 26T 4-Speed 77-86 (#35067)

Zodiac (Genuine Zodiac Products)

#231531

£132.35£119.12

Member£112.50-15%

Zodiac (Genuine Zodiac Products) GZP Mainshaft, BT41-64 (#35040-50)

GZP Mainshaft, BT41-64 (#35040-50)

Zodiac (Genuine Zodiac Products)

#231584

£126.20£113.58

Member£107.27-15%

Jims Transmission Bearing Race, BT37-E77, Standard

Transmission Bearing Race, BT37-E77, Standard

Jims

#231579

£124.46£112.01

Member£105.79-15%

Eastern MC Parts Countershaft 2nd Gear, BT79-86

Countershaft 2nd Gear, BT79-86

Eastern MC Parts

#234580

£123.86£111.47

Member£105.28-15%

V-Twin ADJUSTABLE TRANSMISSION PLATE FOR 4-SPEED BIG TWIN

ADJUSTABLE TRANSMISSION PLATE FOR 4-SPEED BIG TWIN

V-Twin

#781054

£123.58£111.22

Member£105.04-15%

V-Twin ADJUSTABLE TRANSMISSION PLATE FOR 4-SPEED BIG TWIN

ADJUSTABLE TRANSMISSION PLATE FOR 4-SPEED BIG TWIN

V-Twin

#781055

£122.45£110.21

Member£104.08-15%

Eastern MC Parts Outer Bearing Race, BT37-E77, +.005" Oversize

Outer Bearing Race, BT37-E77, +.005" Oversize

Eastern MC Parts

#237920

£120.98£108.88

Member£102.83-15%

Eastern MC Parts TRANSMISSION GEARS & SHAFTS FOR 4-SPEED BIG TWIN

TRANSMISSION GEARS & SHAFTS FOR 4-SPEED BIG TWIN

Eastern MC Parts

#237919

£118.10£106.29

Member£100.39-15%

Zodiac (Genuine Zodiac Products) GZP Mainshaft, BT70-84 #35039-70A(80)

GZP Mainshaft, BT70-84 #35039-70A(80)

Zodiac (Genuine Zodiac Products)

#231586

£116.75£105.08

Member£99.24-15%

V-Twin Mainshaft, BT65-69 (#35039-65T)

Mainshaft, BT65-69 (#35039-65T)

V-Twin

#758561

£111.62£100.46

Member£94.88-15%

Zodiac (Genuine Zodiac Products) GZP Mainshaft, BT65-69 (#35039-65T)

GZP Mainshaft, BT65-69 (#35039-65T)

Zodiac (Genuine Zodiac Products)

#231585

£111.10£99.99

Member£94.44-15%

Andrews ANDREWS STOCK 3RD GEAR (1.23 RATIO)

ANDREWS STOCK 3RD GEAR (1.23 RATIO)

Andrews

#237272

£106.97£96.27

Member£90.92-15%

V-Twin Shifter Cam Plate, BT79-86

Shifter Cam Plate, BT79-86

V-Twin

#789222

£104.22£93.80

Member£88.59-15%

V-Twin Ratchet Top Pawl Carrier, BT52-79

Ratchet Top Pawl Carrier, BT52-79

V-Twin

#768011

£102.50£92.25

Member£87.13-15%

V-Twin Shift Lever Shaft, BT79-86

Shift Lever Shaft, BT79-86

V-Twin

#789230

Member£84.22-15%

Eastern MC Parts Countershaft 2nd Gear, 21T, 36-79 (#35751-36)

Countershaft 2nd Gear, 21T, 36-79 (#35751-36)

Eastern MC Parts

#231537

Member£83.22-15%

Eastern MC Parts Countershaft Low Gear, 26T, FL36-84

Countershaft Low Gear, 26T, FL36-84

Eastern MC Parts

#234579

Member£83.22-15%

V-Twin Speedometer Gear, 7T, Early (#35635-36)

Speedometer Gear, 7T, Early (#35635-36)

V-Twin

#781049

Member£77.45-15%

V-Twin Speedometer Gear, 4T (#35635-62)

Speedometer Gear, 4T (#35635-62)

V-Twin

#781050

Member£76.48-15%

V-Twin 4 SPEED BIG TWIN TRANSMISSION MOUNTING PLATES

4 SPEED BIG TWIN TRANSMISSION MOUNTING PLATES

V-Twin

#781180

Member£66.80-15%

V-Twin 4 SPEED BIG TWIN TRANSMISSION MOUNTING PLATES

4 SPEED BIG TWIN TRANSMISSION MOUNTING PLATES

V-Twin

#781179

Member£66.31-15%

V-Twin ROTARY TOP ASSEMBLIES FOR 4-SPEED BIG TWIN

ROTARY TOP ASSEMBLIES FOR 4-SPEED BIG TWIN

V-Twin

#781053

£1731.89 £1558.70

Member £1472.11 -15%

V-Twin COMPLETE 4-SPEED BIG TWIN RATCHET TOPS

COMPLETE 4-SPEED BIG TWIN RATCHET TOPS

V-Twin

#768020

£808.09 £727.28

Member £686.88 -15%

V-Twin 4 SPEED BIG TWIN TRANSMISSION CASES

4 SPEED BIG TWIN TRANSMISSION CASES

V-Twin

#781047

£703.87 £633.48

Member £598.29 -15%

V-Twin COMPLETE 4-SPEED BIG TWIN RATCHET TOPS

COMPLETE 4-SPEED BIG TWIN RATCHET TOPS

V-Twin

#768018

£669.13 £602.22

Member £568.76 -15%

V-Twin COMPLETE 4-SPEED BIG TWIN RATCHET TOPS

COMPLETE 4-SPEED BIG TWIN RATCHET TOPS

V-Twin

#768021

£661.16 £595.04

Member £561.99 -15%

V-Twin Hand Shifter Jockey Top, BT37-54

Hand Shifter Jockey Top, BT37-54

V-Twin

#789823

£563.22 £506.90

Member £478.74 -15%

V-Twin 4 SPEED BIG TWIN TRANSMISSION CASES

4 SPEED BIG TWIN TRANSMISSION CASES

V-Twin

#781046

£540.43 £486.39

Member £459.37 -15%

Jims JIMS 4 SPEED TRANSMISSION REBUILD KITS

JIMS 4 SPEED TRANSMISSION REBUILD KITS

Jims

#237344

£530.16 £477.14

Member £450.64 -15%

Jims JIMS 4 SPEED TRANSMISSION REBUILD KITS

JIMS 4 SPEED TRANSMISSION REBUILD KITS

Jims

#235888

£326.34 £293.71

Member £277.39 -15%

V-Twin Ratchet Top Shifter Cam, FX76-79

Ratchet Top Shifter Cam, FX76-79

V-Twin

#768002

£295.00 £265.50

Member £250.75 -15%

Andrews ANDREWS 4 SPEED TRANSMISSION MAIN SHAFTS

ANDREWS 4 SPEED TRANSMISSION MAIN SHAFTS

Andrews

#237150

£288.22 £259.40

Member £244.99 -15%

Andrews ANDREWS 4 SPEED TRANSMISSION MAIN SHAFTS

ANDREWS 4 SPEED TRANSMISSION MAIN SHAFTS

Andrews

#234726

£276.44 £248.80

Member £234.97 -15%

Eastern MC Parts Countershaft Gear, 15x17, 69-76 (#35700-69)

Countershaft Gear, 15x17, 69-76 (#35700-69)

Eastern MC Parts

#231590

£274.82 £247.34

Member £233.60 -15%

Andrews ANDREWS 4 SPEED TRANSMISSION MAIN SHAFTS

ANDREWS 4 SPEED TRANSMISSION MAIN SHAFTS

Andrews

#234728

£274.30 £246.87

Member £233.16 -15%

Eastern MC Parts Main Drive Gear, 26T 4-Speed 38-77 (#35065-65B)

Main Drive Gear, 26T 4-Speed 38-77 (#35065-65B)

Eastern MC Parts

#231530

£258.32 £232.49

Member £219.57 -15%

Andrews ANDREW STOCK MAIN DRIVE GEARS

ANDREW STOCK MAIN DRIVE GEARS

Andrews

#234717

£214.00 £192.60

Member £181.90 -15%

V-Twin Countershaft 3rd & 4th Cluster Gear

Countershaft 3rd & 4th Cluster Gear

V-Twin

#731708

£212.99 £191.69

Member £181.04 -15%

Andrews ANDREW STOCK MAIN DRIVE GEARS

ANDREW STOCK MAIN DRIVE GEARS

Andrews

#234718

£212.65 £191.39

Member £180.75 -15%

Eastern MC Parts Countershaft 3rd & 4th Cluster Gear

Countershaft 3rd & 4th Cluster Gear

Eastern MC Parts

#731706

£206.08 £185.47

Member £175.17 -15%

MCS Clutch gear, transmission. 14t

Clutch gear, transmission. 14t

MCS

#971277

£199.51 £179.56

Member £169.58 -15%

V-Twin Countershaft 3rd & 4th Cluster Gear

Countershaft 3rd & 4th Cluster Gear

V-Twin

#731707

£189.07 £170.16

Member £160.71 -15%

Andrews ANDREWS 1ST GEAR SETS FOR 4 SPEED TRANSMISSIONS

ANDREWS 1ST GEAR SETS FOR 4 SPEED TRANSMISSIONS

Andrews

#234710

£184.99 £166.49

Member £157.24 -15%

Andrews ANDREWS STOCK 3RD GEAR (1.23 RATIO)

ANDREWS STOCK 3RD GEAR (1.23 RATIO)

Andrews

#234715

£184.06 £165.65

Member £156.45 -15%

Andrews ANDREWS 1ST GEAR SETS FOR 4 SPEED TRANSMISSIONS

ANDREWS 1ST GEAR SETS FOR 4 SPEED TRANSMISSIONS

Andrews

#234709

£183.74 £165.37

Member £156.18 -15%

V-Twin Hand Shifter Shift Drum Jockey Top

Hand Shifter Shift Drum Jockey Top

V-Twin

#789928

£182.23 £164.01

Member £154.90 -15%

Eastern MC Parts M1+M2 Cluster Gear, BT59-84

M1+M2 Cluster Gear, BT59-84

Eastern MC Parts

#231581

£162.08 £145.87

Member £137.77 -15%

Eastern MC Parts 1952-1979 FOOT SHIFT RATCHET TOP

1952-1979 FOOT SHIFT RATCHET TOP

Eastern MC Parts

#232778

£148.33 £133.50

Member £126.08 -15%

Zodiac (Genuine Zodiac Products) GZP Main Drive Gear, 26T 4-Speed 77-86 (#35067)

GZP Main Drive Gear, 26T 4-Speed 77-86 (#35067)

Zodiac (Genuine Zodiac Products)

#231531

£132.35 £119.12

Member £112.50 -15%

Zodiac (Genuine Zodiac Products) GZP Mainshaft, BT41-64 (#35040-50)

GZP Mainshaft, BT41-64 (#35040-50)

Zodiac (Genuine Zodiac Products)

#231584

£126.20 £113.58

Member £107.27 -15%

Jims Transmission Bearing Race, BT37-E77, Standard

Transmission Bearing Race, BT37-E77, Standard

Jims

#231579

£124.46 £112.01

Member £105.79 -15%

Eastern MC Parts Countershaft 2nd Gear, BT79-86

Countershaft 2nd Gear, BT79-86

Eastern MC Parts

#234580

£123.86 £111.47

Member £105.28 -15%

V-Twin ADJUSTABLE TRANSMISSION PLATE FOR 4-SPEED BIG TWIN

ADJUSTABLE TRANSMISSION PLATE FOR 4-SPEED BIG TWIN

V-Twin

#781054

£123.58 £111.22

Member £105.04 -15%

V-Twin ADJUSTABLE TRANSMISSION PLATE FOR 4-SPEED BIG TWIN

ADJUSTABLE TRANSMISSION PLATE FOR 4-SPEED BIG TWIN

V-Twin

#781055

£122.45 £110.21

Member £104.08 -15%

Eastern MC Parts Outer Bearing Race, BT37-E77, +.005" Oversize

Outer Bearing Race, BT37-E77, +.005" Oversize

Eastern MC Parts

#237920

£120.98 £108.88

Member £102.83 -15%

Eastern MC Parts TRANSMISSION GEARS & SHAFTS FOR 4-SPEED BIG TWIN

TRANSMISSION GEARS & SHAFTS FOR 4-SPEED BIG TWIN

Eastern MC Parts

#237919

£118.10 £106.29

Member £100.39 -15%

Zodiac (Genuine Zodiac Products) GZP Mainshaft, BT70-84 #35039-70A(80)

GZP Mainshaft, BT70-84 #35039-70A(80)

Zodiac (Genuine Zodiac Products)

#231586

£116.75 £105.08

Member £99.24 -15%

V-Twin Mainshaft, BT65-69 (#35039-65T)

Mainshaft, BT65-69 (#35039-65T)

V-Twin

#758561

£111.62 £100.46

Member £94.88 -15%

Zodiac (Genuine Zodiac Products) GZP Mainshaft, BT65-69 (#35039-65T)

GZP Mainshaft, BT65-69 (#35039-65T)

Zodiac (Genuine Zodiac Products)

#231585

£111.10 £99.99

Member £94.44 -15%

Andrews ANDREWS STOCK 3RD GEAR (1.23 RATIO)

ANDREWS STOCK 3RD GEAR (1.23 RATIO)

Andrews

#237272

£106.97 £96.27

Member £90.92 -15%

V-Twin Shifter Cam Plate, BT79-86

Shifter Cam Plate, BT79-86

V-Twin

#789222

£104.22 £93.80

Member £88.59 -15%

V-Twin Ratchet Top Pawl Carrier, BT52-79

Ratchet Top Pawl Carrier, BT52-79

V-Twin

#768011

£102.50 £92.25

Member £87.13 -15%

V-Twin Shift Lever Shaft, BT79-86

Shift Lever Shaft, BT79-86

V-Twin

#789230

£99.08 £89.17

Member £84.22 -15%

Eastern MC Parts Countershaft 2nd Gear, 21T, 36-79 (#35751-36)

Countershaft 2nd Gear, 21T, 36-79 (#35751-36)

Eastern MC Parts

#231537

£97.91 £88.12

Member £83.22 -15%

Eastern MC Parts Countershaft Low Gear, 26T, FL36-84

Countershaft Low Gear, 26T, FL36-84

Eastern MC Parts

#234579

£97.91 £88.12

Member £83.22 -15%

V-Twin Speedometer Gear, 7T, Early (#35635-36)

Speedometer Gear, 7T, Early (#35635-36)

V-Twin

#781049

£91.12 £82.01

Member £77.45 -15%

V-Twin Speedometer Gear, 4T (#35635-62)

Speedometer Gear, 4T (#35635-62)

V-Twin

#781050

£89.98 £80.98

Member £76.48 -15%

V-Twin 4 SPEED BIG TWIN TRANSMISSION MOUNTING PLATES

4 SPEED BIG TWIN TRANSMISSION MOUNTING PLATES

V-Twin

#781180

£78.59 £70.73

Member £66.80 -15%

V-Twin 4 SPEED BIG TWIN TRANSMISSION MOUNTING PLATES

4 SPEED BIG TWIN TRANSMISSION MOUNTING PLATES

V-Twin

#781179

£78.01 £70.21

Member £66.31 -15%

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