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Tired of shaking your teeth out on a 100-mile ride? Replace your old crankshaft with an Ultima® professionally balanced crankshaft. Lightweight racing connecting rods and our exclusive balancing system makes these an
exceptional value. This is the core of your engine and can make or break your ride quality. These crankshafts use Jims Machining shafts and pins and late style bearings. Both replacement and high performance match balanced
pistons kits are available in standard and oversizes for 80”, 89”, 96”, 100”,
107" & 113” engines. Sold each.

5 PIECE CRANKSHAFTS

98-550 4.625 Stroke replacement crankshaft. Available to replace cranks on 1984 thru 1999 model Evolution® 96” engines and will replace cranks on most 89” & 106” engines using 4-5/8” strokes, check piston weight for balance factor. See NOTE 1 below.
98-552 4.25 Stroke replacement crankshaft. Available as replacement crankshafts on 1984 thru 1999 model Evolution® 80” engines and will replace shaker cranks on most 88” & 97” engines using 4-1/4” strokes, and stock length pinion shafts.
See NOTE 1 below.
98-553 4.5 Stroke 4” bore replacement crankshaft . Available as replacemet crank-shaft on 1984 thru 1999 model Evolution® 113” engines using 4” bore and 1/4” longer pinion shaft. Crank has 7.44” rods and
.792” pins.
98-554 4-1/4” Stroke 4" bore replacement crankshaft with 1/4" longer pinion shaft.
For 100” engines.
98-523 4.000” stroke, 1984 thru 1999 model Evolution style engines with the 1/4” longer pinion shaft. Great replacement for S&S® 100” motors.

98-524 4.625” stroke, Shovelhead, used in our Ultima® 96” Shovelhead motor. Has a standard length pinion shaft and features heavy counter weights to allow for balancing for a wide variety of piston weights.

3 PIECE CRANKSHAFTS

Rods are 7.700" w/ 0.927" pins
98-559 4.000 stroke. replace cranks on 1984 thru 1999
98-555 4.250 stroke, used in our Ultima® 120”
98-522 4.375 stroke, used in our Ultima® 124”
98-556 4.500 stroke, used in our Ultima® 127”
98-599 4.625 stroke, used to make a 131”

Rods are 8.000" w/ 0.927" pins
98-579 4.250 stroke, used in our Ultima® 130”
98-557 4.625 stroke, used in our Ultima® 140”

Rods are 8.000" w/ 0.927" pins
98-579 4.250 stroke, used in our Ultima® 130”
98-557 4.625 stroke, used in our Ultima® 140”

Rods are 7.440" w/ 0.927" pins
98-631 4.250 stroke used in our Ultima® 100/107”
98-521 4.500 stroke used in our Ultima® 113”
98-567 4.625 stroke, used to make a 117”


Crank


Ultima® Crankshafts
NOTE 1: This shaft has a long bushing end allowing it to be used on 1990 & later model engines with the stronger 1984 thru 1999 style pinion shaft gear components used. You must order Midwest part No. 98-570 pinion conversion package if using on 1990 & later engines.

5-Piece

5-Piece Crankshaft

1. Flywheel forging 2. 98-421 1-20 nut 3. 98-422 .75-20 nut 4. 98-573 Connecting rod set
5. H95-145 Crank race set 6. 95-259 Roller bearing set 7. H95-146 Wrist pin insert
8. 98-537 Crank pin - 1.250 w/nuts & key 9. 98-539 1.125-16 nut 10. 98-475 Key, OEM#23985-18
11. 94-137 Key, OEM#23985-12 12. 98-546 Pinion shaft 13. 98-339 Sprocket Shaft

3-Piece Fly

3-Piece Crankshaft

1. 98-555 Midwest pinion 4.625 2. 98-548 Crank pin 3. 98-575 Connecting rod set
4. 95-307 Roller bearing set 5. 95-147 Rod race set 6. 41-179A Freeze plug 7. 98-601 External retaining ring
8. 95-144 Wrist pin insert / 95-148 Wrist pin insert +0.002 OS 9. 95-810 Inner pinion race 1.500" /
95-811 Inner pinion race1.625"

 

See Below
for Exploded
Views of
3- Piece &
5-Piece
Flywheels