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 $ 600.00 Lighter Weight Flywheels $ 550.00
Flywheels for 74" & 80" OHV models are available in
Lighter Weight or Torquemonster version.
*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 1936-1952 61"OHV are made with the 1941-later 74"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/Pan engines.
*Please Note*Flywheels for Evolution Sportster models require the use of special "big taper" S&S brand sprocket shaft and pinion shaft. Flywheels are NOT available in stock stroke. Pistons must be custom made. Other parts such as pinion gears and bearings must also be changed.