Truett & Osborn Flywheels

Part numbers for Truett & Osborn Flywheels are determined by combining the model code and the desired stroke length.  This chart lists replacement flywheels (stock cubic inch displacement) by year and model.  See stroke availability chart below for additional stroke lengths.  Big Twin flywheels from 1939-1999 are available in two different styles (TorqueMonster Weight & Lighter Weight).  The TorqueMonster flywheels are direct replacement weight (heavy) for years 1930-1981.  The left side flywheel is much wider and heavier than the right side.  The Lighter weight flywheels are the same width and weight for both right and left sides (similar to Evolution flywheels and S&S).  Late Shovelheads and Evolutions from 1982-1999 the Lighter weight would be the direct replacement weight.  TorqueMonster weight is available for these models as an option to increase low-end torque in Evos. 

TorqueMonster Flywheels     $  475.00                                                  Lighter Weight Flywheels     $  425.00

YEAR/MODEL FITMENT

SPECIFICATIONS

MODEL CODES

Years

Engine Size/Model

Stock Stroke

Outside  Diameter

Notes

TorqueMonster Weight

Lighter Weight

1929-1973

Harley 45”

3 13/16

7 7/8

 

 

HD45

1929-1973 Special HD 45"

3 13/16

7 7/8

Uses XL C-pin/Rods

*

HD45XL

             

1952-1953

K-model

3 13/16

7 7/8

Press in shafts&C-pin

*

52K

1954-1956

KH-model

4 9/16

7 7/8

Lip on sprocket hole

*

54KH

             

1958-1970

XLR-model

3 13/16

7 7/8

 

*

XLR

1957-E1981

Sportster

3 13/16

7 7/8

 

 

EXL

L1981-1985

Sportster

3 13/16

7 7/8

 

 

LXL

1986-2003

Sportster*

3 13/16

7 7/8

S&S special shafts*

*

EVXL

             
1912-1914 61" Twin Cylinder

3 1/2

8"

 

*

1912

1915-1929

61” J model

3 1/2

8 7/8

 9" O.D. also avail.

*

J

1921-1929

74” JD model

3 31/32

8 3/4

 9" O.D. also avail.

*

JD

             

1930-1936

74” Flathead

3 31/32

8 1/8

 4" stroke also avail.

30T

 

     1936 80" Flathead

4 1/4

8 1/8

 

30T

 

1937-1948

74”/80”Flathead*

4 9/32

8 9/32

Use 1941-later C-pin*

37T

 

             

1936-1940

61” Knucklehead*

3 ½

8 1/8

Use 1941-later C-pin*

36T

 

1941-1947

61” Knucklehead

3 ½

8 ½

 

39T

 

1948-1952

61” Panhead

3 ½

8 ½

 

39T

 

             

1941-1954

74” Pan/Knuckle

3 31/32

8 ½

 

39T

39

     1955 74" Panhead

3 31/32

8 ½

56-64 Sprocket Shaft

56T

56

1956-1969

74” Pan/Shovel

3 31/32

8 ½

 

56T

56

1970-1971

74” Shovelhead

3 31/32

8 ½

 

70T

56

1972-1981

74” Shovelhead*

3 31/32

8 ½

82-up Sprocket Shaft*

82/72T

82/72

1972-1981

80” Shovelhead*

4 Ό

8 ½

82-up Sprocket Shaft*

82/72T

82/72

1982-1984

80” Shovelhead

4 Ό

8 ½

 

82T

82

1985-1999

80” Evolution

4 Ό

8 ½

 

82T

82

 

 * = Available at extra charge for reducing outside diameter *see note*                                                      x = Available

Model Code & Stroke

3 1/2" 3-13/16" 3-31/32" 4" 4-1/4" 4-5/16" 4 9/32" 4-7/16" 4 9/16" 4-1/2" 4-5/8" 4-3/4" 5"
HD45   x           x   x x    
45XL (XL C-pin)   x           x   x x    
52K   x                      
54KH                 x        
XLR (Race XL)   x                      
EXL & LXL   x     x         x x x x
EVXL           x             x
J & JD Model x   x   x         x x x  
30T (flathead)     x x x                
37T (flathead)     *   *   x     * * * *
36T (OHV) x   *   *         * * * *
39 & 39T x   x   x         x x x x
56 & 56T     x   x         x x x x
70T     x                    
82/72 & 82/72T     x   x         x x x x
82 & 82T         x         x x x x

Flywheels for 74" & 80" OHV models are available in Lighter Weight or Torquemonster version.
Flywheels for 61" OHV & Big Twin Flathead models are only available in Torquemonster version.*see note*
Flywheels for 45" Flathead, K-model, Sportster,  JD, and Indian models only available in stock Weight.

*Please Note*JD ,45XL, XLR, EVXL, K, KH, and Indian flywheels are specialty flywheels, priced the same as Torquemonster Flywheels.  The Harley 45" flywheels & Sportster flywheels are priced the same as Lighter Weight Flywheels.

*Please Note*1972-1981 Original Harley flywheels used sprocket shaft part # 24001-72.  This shaft was very large taper, set at  8 degrees, and had a lot of problems with slippage in the flywheel.  We make our flywheels for these years to use the 1982-later 23909-80 shaft.

*Please Note*Flywheels for 1937-1948 Big Twin Flathead and 1936-1940 61" Knucklhead are made with the 1941-later OHV crankpin, NOT the stepped crankpin as original.  I only make the stock stroke flywheels (4-9/32 & 3-1/2) in the TorqueMonster version, but since we make them with the later crankpin, the only difference between these and 1939-later OHV flywheels is the outside diameter.  We can take a set of 1939-later OHV Lighter Weight or TorqueMonster flywheels that are available in other strokes and turn the O.D. to be used in Flathead or 61" Knuckle engines.

*Please Note*Flywheels for Evolution Sportster models require the use of special "big taper" S&S brand sprocket shaft and pinion shaft. Other parts such as pinion gears and bearings must also be changed, depending on the year/model.

Indian Flywheels

YEAR/MODEL FITMENT

SPECIFICATIONS

MODEL CODES

Years

Engine Size/Model

Stock Stroke

Outside  Diameter

Notes

TorqueMonster Weight

Lighter Weight

1916-1924 61" Power Plus

3 31/32

8"

 

*

IPP

1928-1931 45"  101 Scout

3 1/2

7 3/4

 

*

IS101

1934-1942 45"  Sport Scout

3 1/2

7 3/4

 

*

IS45

1934-1942 45"  Sport Scout

stroker only

7 3/4

Uses XL C-pin/Rods

*

IS45XL

 

Model Code & Stroke

3 1/2" 3 31/32" 4-7/16" 4 13/16" 5" 5 1/4" 5 1/2"
IPP        - Indian Power Plus   X          
IS101    - 101 Scout models X            
IS45      - Sport Scout models X   X        
IS45XL - Sport Scout  (XL C-pin)     X