This is a brand-new quality product made in America by the famous “Truett & Osborn” company for the Indian “Sport Scout” (640 or FDA, etc.) 45” (750cc) engines produced from approximately 1936-48, for street or racing use. In addition, they may be installed in similar Indian engines such as the 30.50” (500cc) military Scout (741 or GDA) and Junior Scout (538 or ECH, etc.) and the older Standard Scout (234 or BCD, etc.). However, there may be minor differences in clearance, skirt length, balance weight, end play etc. which will require expert assembly.

    Victory is the sole and exclusive source of these Scout stroker flywheels, which are exactly what you need as the foundation for your high-performance Sport Scout. The photo is not the actual flywheels, which will closely resemble the original flywheels.
    Nothing adds torque like stroker flywheels! Gives you the power for high cruising speed, and better acceleration. They also increase compression by more than 1 full ratio; engines with 5:1 compression becomes 6.1:1, 6:1 compression ratio become 7.3:1. The new stroke is 4-7/16” (4.4375”), or 15/16” (.9375”) longer than the original stroke and increases engine size by 26.8%. This is the same stroke as the traditional Indian Chief flywheels used to stroke Scout engines for 70 years, but now difficult to find in usable shape and expensive to purchase as a new reproduction. The new engine size with the original 2-7/8&rdquo (2.875”) std. bore pistons is 57.6”, or 944cc. This is the only stroke length available.

    This stroke length increase, when used with the slightly longer Sportster connecting rod (7.4375”), gives a slightly taller “CD”, or compression distance (+.0355”) than the original 7.402” Scout rod, and will require minor additional work to use the Scout stroker piston shown here (not included, click the picture to see a larger version), which is available from

. This work may consist of a .0355” cylinder base shim, or minor machining to the piston, cylinder flange, or head gasket surface, or a pop-up relief in the head. I cannot supply or modify these parts or pistons.

    These flywheels require the common and inexpensive Harley-Davidson Sportster rod set with its much larger 1¼” crankpin and bearings (not included) and cannot be used with any Indian rod. The larger taper and higher crankpin nut torque lock the flywheel halves together much more securely than even new original Sport Scout parts, which reduces wear and vibration due to flywheel flex. The Sportster rods are much stronger than any Scout rods, and of course need not be rebuilt since they’re available new from H-D, as an excellent reproduction, and in heavy-duty from Carrillo, S&S etc. although the stock Sportster rod is more than sufficient even for racing.

    For the experienced engine builder, Sportster rods are available in many different length to make your special project easier, but I cannot supply them.
    As shown in the table below, alternate rod lengths will give different rod to stroke ratios and permit adjustments to be made to the total height of the engine, or to the piston. “Effect on CD” is by comparison with a std. Sportster rod. Please note that longer rods produce a higher (more favorable) rod ratio, but reduce the compression distance and require either a special piston, stroker plates, or both. It is extremely important that the piston dome’s distance to the head’s quench surface at TDC is between .035” (minimum) and .050” (maximum), and the choice of rod length, piston dimensions and cylinder height must all be calculated to achieve this. Expert engine builders: substitute your own figures here. Do not use shorter rods to reduce compression ratio.

Sportster Rods

Rod type

Length on centers

Rod to stroke ratio

Effect on CD

1983-84 XR1000 & 1985-* Evo 883, 1100, 1200    

6.9260”

1.561:1

+.5115”

S&S #7900 special length

7.1130”

1.603:1

+.3245”

Buell XB9

7.2700”

1.638:1

+.1675”

1952-56 K, KH; 1957-85 ironhead 900 & 1000

7.4375”

1.676:1

+.0000”

Carrillo

7.8000”

1.758:1

-.3625”

8.0000”

1.803:1

-.5625”

    This is a very reasonable investment - it’s only a small part of your total project cost, and does more in one step than anything else - more than hot cams, bigger carburetor, etc., although those parts will work even better on your stroker engine. The new larger high-compression engine will be less sensitive to big cams and carburetors, so you have more tuning options while retaining great low speed power.     The flywheel material is far superior to the original factory cast-iron, even the preferred late model “Z” metal. Every individually crafted flywheel begins as a 80-55-06 ductile (nodular) iron blank, which is then heat-treated to 220-250 BHN. The 80,000 pound tensile strength blanks undergo an exacting 20-step manufacturing process, utilizing both CNC and conventional precision milling and machining. This insures accurate surfaces, legendary reliability, and excellent “truability”, an absolute necessity when setting up high performance engines to blueprint specifications. If properly installed and maintained, they will not wear out, but give many years of trouble-free service.
    Ductile cast-iron is the superior material for flywheels, since its surface provides a better “grip” on the crankpin and shaft tapers than a steel forging to prevent slippage. Cast-iron also damps out internal vibrations better than steel.         This is more complex than a normal rebuild, requiring prior experience and other assembly work. Victory does not supply pistons, modify pistons, or install these parts. Flywheels must be balanced to your components.     Stroking your Indian Junior Scout or 741 with H-D 45 flywheels? These pistons may be of interest, click here for more information: 

This item is not available yet, shipping date is approximately October 31, 2008. Do not order, all payments will be refunded. Click here to receive notification when these flywheels are available: .