BIG TWIN: 4 SPEED TRANSMISSIONS
Big Twin 4 speed transmissions have been built since 1936 in several versions. They were included on bikes with Knuckle engines, Pans, Shovels and some '84 and '85 Evolution 80's. They all used this transmission. With Andrews 4 speed gears, transmissions last longer, shift faster, and just plain run better. Bikes with Andrews gears feel so good that it’s hard to believe until you experience the difference for yourself.
BIG TWIN COMPLETE 4 SPEED TRANSMISSION GEAR KITS
Gear kits must be ordered by part numbers listed below which specify year and 1st and 3rd ratios. Each gear kit includes 6 gears, 2 shift clutches and 2 forks as shown on previous page. (Shafts and small parts kits must be ordered separately).
TEC # Andrews # Description Years
84476 210150 (2.44 1st, 1.35 3rd) (1936-1976)
84477 210250 (2.44 1st, 1.23 3rd) (1936-1976)
84478 210350 (2.60 1st, 1.35 3rd) (1936-1976)
84479 210450 (2.60 1st, 1.23 3rd) (1936-1976)
84480 210550 (2.44 1st, 1.35 3rd) (1977-1984)
84481 210650 (2.44 1st, 1.23 3rd) (1977-1984)
84482 210750 (2.60 1st, 1.35 3rd) (1977-1984)
84483 210850 (2.60 1st, 1.23 3rd) (1977-1984)
 
BIG TWIN:  4 SPEED TRANSMISSION GEAR SETS
2.44 1ST GEAR SET (1959 thru 1984)
TEC # Andrews # Description
84400 201105 Best choice for Superglides, choppers and lighter bikes with stock or smaller motor or trans sprockets. This is a ‘no clunk’, 48 mph, 1st gear. Installation in '80-84 FX requires 21T (1.82 ratio) 2nd gear for this 1st gear.
 
2.60 1ST GEAR SET (1959 thru 1984)
84401 201145 This gear set works best with “E” glides and heavier bikes with motor or trans sprockets having more teeth than stock sprockets. Installation in '80-84 FX requires 21T (1.82 ratio) 2nd gear for this 1st gear.
 
3.00 1ST GEAR SET (Original stock ratio)
84393 201090 (1959 thru 1984) Stock replacement first cluster and countershaft gear. Cluster gear has 15 and 20 teeth; counter has 26 teeth. 1936 version has no rear counterbore and requires short length 3rd main gear part #206215
84392 201094 (1936 thru 1958)
 
 
BIG TWIN:  4 SPEED TRANSMISSION GEARS
COMBINATION 2.24 1ST- 1.65 2ND GEAR SET
84402 201020 If you want peak RPM thru the quarter mile, this gear set will provide the super close ratio shifting to handle it. OK for street or drags with any size motor.
 
 
STOCK 2ND GEAR (1.82 RATIO)
84403 202160 35751-36) Stock 2nd gear with face milled drive dogs for more positive 1-2 shifts. This 21 tooth gear fits 1941-1979. It will also fit later transmissions but requires one of the first gear sets shown above.
 
CLOSE RATIO 3RD GEAR SET (1.35 RATIO)
84405 203365 Early Transmissions built before mid 1976, to serial# U-8958 (or lower) with loose needle bearings.
84406 203375 Late For transmissions built after mid 1976, from serial# U-8959 (or higher) with caged needle bearings. New design drive slots include lead in ramps for quicker, more positive shifting (same as stock 3rd and 4th gears).
 
STOCK 3RD GEAR (1.23 RATIO)
84404 206220 (Mainshaft 3rd) (replaces H/D# 35306-59)
84420 206215 (Mainshaft 3rd) (replaces H/D# 35306-36)
(This gear requires 1936-58 style cluster gear)
 
84408 206330 Cluster: 36-76 (replaces H/D# 35700-36)
84409 206335 Cluster: 76-86 (replaces H/D# 35700-76)
  Replacements for stock main and countershaft 3rd. The design of drive slots on mainshaft gear has been upgraded to include lead-in ramps for quicker, more positive shifting.
 
STOCK MAIN DRIVE GEAR (4TH)
84410 204260 (1936-1976) Early (replaces H/D# 35065-65)
84412 204280 (1977-1986) Late (replaces H/D# 35067-77 and 35067- 84)
  Replacement 4th gears are made with wider drive slots and steeper lead-in ramps for more positive 3-4 shifting. The "O" ring groove addition is a design update for all chain drive (1977-1984) 4th gears
 
Shift Clutches
84450 205120 (1-2 clutch) (replaces H/D# 35665-36)
84452 205340  (3-4 clutch) (replaces H/D# 35440-38)
  Replacement clutches are specially heat treated and shot peened for super durability. 3-4 clutches are face milled and have longer lead in ramps for more positive shifts.
 
Shift Forks
84456 209750 (1-2 fork) (replaces H/D# 34159-36)
84458 209760 (3-4 fork) (replaces H/D# 34158-36)
  One piece cold forged forks. Fully heat treated and black oxide coated, a must for all transmission rebuilds.
 
 
TRANSMISSION MAINSHAFTS

TEC # Andrews Years   Replaces
84464 208500 1937-1964 early 35040-50
84465 208650 1965-1969 mid 35039-65
84470 208700 1970-1985 chain late 35039-70A
84471 208800 Late 1984-'86 belt drive late 35039-85
Replacement mainshafts for all versions of big twin boxes. Made from aircraft alloy steel. Heat treated and finish ground to ensure maximum durability.
 

TRANSMISSION COUNTERSHAFTS

Picture to come

TEC # Andrews Years Replaces
84460 207650 1941-early '76 35614-65
84462 207770 1976-79 35614-77
84463 207800 1980-85 35614-80
Three types of countershafts fit transmissions thru 1985. They are not interchangeable, so make sure before you order.