Jims Catalogue

FLYWHEEL ASSEMBLIES

PRESSED EVO STROKER KITS CARBURETOR ONLY

Unmatched strength for your EVO! Your next high performance EVO engine build will be more reliable with JIMS ® new EVO/Twin Cam ® hybrid crank assembly. We have integrated the strength and stiffness of the genuine Harley ® Twin Cam ® crank pin and bearings into our new Evo crankshaft assembly. Each left flywheel and shaft is forged as a unit to maxi- mize stiffness and reliability. Of course, we use the proven JIMS ® “H” beam 4340 chromoly connecting rods for the ultimate in strength and stability. This is the strongest and most rigid EVO crankshaft made. The bolt together EVO crankshaft has some limits when run at high rpm in powerful engines. The taper-fit crank pin flexes at high rpm and can often shift, even in normal use. Harley choose to enlarge the pin diameter and make it a press fit in flywheels of the Twin Cam ® engine. This greater rigidity and load capacity is perhaps the greatest advantage of the Twin Cam ® engine over the EVO. JIMS ® new EVO crankshaft goes a long way to narrow the difference in strength between the two engines. These kits are shipped with standard length sprocket and pinion shafts. These kits can be installed into 1984-99 cases with standard pinion shaft races (24599-58B, 24599-58A, etc.). 24628-87 pinion bearings may also be used. For 3-5/8” bore pistons, motor cases will have to be bored to install 3-5/8” cylinders. See JIMS ® Evo case bore tool No.1409 on page 168. For 1990-99 motors, use JIMS ® pinion gear No.24043-78, JIMS ® oil pump drive gear No.26349-84 (with JIMS ® Keys 2480K), and JIMS ® Nut 24023-54. • Parts not available separately, except piston sets. For more details see No.1972-IS instructions

7.440” Length H Beam Construction

.792” Wrist Pin Dia.

2

4340 Chromoly Material

Pressed Plug For Increased Flywheel Retention

Forged Precision Machined Flywheels

RACE ONLY

JIMS ® Forged Precision Machined Pistons

80” EVOLUTION ® STROKER KITS WITH DOMED PISTONS

PART NO. No. 1976 No. 1977 No. 1978

APPLICATION

STROKE

BORE

FLYWHEEL DIA.

COMPRESSION RATIO

Use on EVO 1984-present Use on EVO 1984-present Use on EVO 1984-present

4 1/4” 4 1/4” 4 1/4”

3 1/2” STD 3 1/2” +.005 3 1/2” +.010

8 1/2” 8 1/2” 8 1/2”

*10:1 *10:1 *10:1

*Compression Ratio Approximate

87” EVOLUTION ® STROKER KITS WITH FLAT TOP PISTONS

PART NO. No. 1979 No. 1980 No. 1981

APPLICATION

STROKE

BORE

FLYWHEEL DIA.

COMPRESSION RATIO

Use on EVO 1984-present Use on EVO 1984-present Use on EVO 1984-present

4 1/2” 4 1/2” 4 1/2”

3 1/2” STD 3 1/2” +.005 3 1/2” +.010

8 1/2” 8 1/2” 8 1/2”

*10:1 *10:1

*10:1 *Compression Ratio Approximate

89” EVOLUTION ® STROKER KITS WITH FLAT TOP PISTONS

PART NO. No. 1982 No. 1983 No. 1984

APPLICATION

STROKE

BORE

FLYWHEEL DIA.

COMPRESSION RATIO

Use on EVO 1984-present Use on EVO 1984-present Use on EVO 1984-present

4 5/8” 4 5/8” 4 5/8”

3 1/2” STD 3 1/2” +.005 3 1/2” +.010

8 1/2” 8 1/2” 8 1/2”

*9.25:1 *9.25:1

*9.25:1 *Compression Ratio Approximate

96” EVOLUTION ® STROKER KITS WITH FLAT TOP PISTONS (SEE JIMS ® CASE BORING TOOL NO.1409) PART NO. APPLICATION STROKE BORE FLYWHEEL DIA. COMPRESSION RATIO No. 1985 Use on EVO 1984-present 4 5/8” 3 5/8” STD 8 1/2” *9.75:1 No. 1986 Use on EVO 1984-present 4 5/8” 3 5/8” +.005 8 1/2” *9.75:1 No. 1987 Use on EVO 1984-present 4 5/8” 3 5/8” +.010 8 1/2” *9.75:1

23

*Compression Ratio Approximate