2012 Engine Kits & Rotating Assemblies

Pro LS 4340 Rotating Assembly, 378 Cid., 4.080 bore, 3.622 stroke, 58x, 6.125 rod, 12cc dish, 9.9:1 @ 65cc, 9.4:1 @ 70cc, File-Fit Rings, H Bearings

Part Number: SUM-R5836L08012

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Pro LS 4340 Piston and Rod Kit, 360 Cid., 3.785 bore, 4.000 stroke, 6.125 rod, 5cc dish, 10.9:1 @ 61cc, 10.4:1 @ 65cc, File-Fit Rings

Part Number: SUM-PR407855

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

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Pro LS 4340 Piston and Rod Kit, 367 Cid., 3.820 bore, 4.000 stroke, 6.125 rod, 5cc dish, 11:1 @ 61cc, 10.5:1 @ 65cc, File-Fit Rings

Part Number: SUM-PR408205

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

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Pro LS 4340 Rotating Assembly, 376 Cid., 4.065 bore, 3.622 stroke, 24X, 6.125 rod, 12cc dish, 9.9:1 @ 65cc, 9.4:1 @ 70cc, File-Fit rings, H Bearings

Part Number: SUM-R2436L06512

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Pro LS 4340 Rotating Assembly, 377 Cid., 4.070 bore, 3.622 stroke, 24X, 6.125 rod, 2cc dome, 11.6:1 @ 65cc, 10.9:1 @ 70cc, File-Fit Rings, H Bearings

Part Number: SUM-R2436L0702

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Pro LS 4340 Rotating Assembly, 376 Cid., 4.065 bore, 3.622 stroke, 58x, 6.125 rod, 2cc dome, 11.6:1 @ 65cc, 11:1 @ 70cc, File-Fit Rings, H Bearings

Part Number: SUM-R5836L0652

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Pro LS 4340 Rotating Assembly, 347 Cid., 3.903 bore, 3.622 stroke, 58x, 6.125 rod, 3cc dome, 11:1 @ 65cc, 10.6:1 @ 68cc, File-Fit Rings, H Bearings

Part Number: SUM-R5836L9033

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Pro LS 4340 Rotating Assembly, 365 Cid., 4.005 bore, 3.622 stroke, 58x, 6.098 rod, 12cc dish, 9.6:1 @ 65cc, 9.2:1 @ 70cc, File-Fit Rings, H Bearings

Part Number: SUM-R583600512

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Pro LS 4340 Rotating Assembly, 346 Cid., 3.898 bore, 3.622 stroke, 58x, 6.098 rod, 3cc dome, 11:1 @ 65cc, 10.6:1 @ 68cc, File-Fit Rings, H Bearings

Part Number: SUM-R58368983

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Pro LS Rotating Assembly, 330 Cid., 3.810 bore, Standard 3.622 stroke, 24X, 6.098 rod, 7cc dish, 9.8:1 @ 61cc, 9.4:1 @ 65cc, File-Fit ring, H Bearings

Part Number: SUM-R24368107

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Pro LS Rotating Assembly, 370 Cid., 4.030 bore, 3.622 stroke, 58x, 6.098 rod, 2cc Flat Top, 10.9:1 @ 65cc, 10.3:1 @ 70cc, File-Fit Rings, H Bearings

Part Number: SUM-R58360302

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Repair Kit, Top End, 79.960mm Bore, 10.20 to 1 Compression Ratio, Polaris, Kit

Part Number: NTI-NA-50080-BK

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

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Pro LS Rotating Assembly, 330 Cid., 3.810 bore, Standard 3.622 stroke, 58x, 6.125 rod, 2cc dome, 11:1 @ 61cc, 10.4:1 @ 65cc, File-Fit Rings, H Bearing

Part Number: SUM-R5836L8102

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Pro LS 4340 Rotating Assembly, 346 Cid., 3.898 bore, 3.622 stroke, 58x, 6.125 rod, 3cc dome, 11:1 @ 65cc, 10.6:1 @ 68cc, File-Fit Rings, H Bearings

Part Number: SUM-R5836L8983

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Pro LS 4340 Rotating Assembly, 359 Cid., 3.780 bore, 4.000 stroke, 58x, 6.125 rod, 5cc dish, 10.9:1 @ 61cc, 10.4:1 @ 65cc, File-Fit Rings, H Bearings

Part Number: SUM-R58407805

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Pro LS 4340 Rotating Assembly, 346 Cid., 3.898 bore, 3.622 stroke, 58x, 6.125 rod, 7cc dish, 9.7:1 @ 65cc, 9.4:1 @ 68cc, File-Fit Rings, H Bearings

Part Number: SUM-R5836L8987

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Pro LS 4340 Rotating Assembly, 347 Cid., 3.903 bore, 3.622 stroke, 58x, 6.125 rod, 7cc dish, 9.7:1 @ 65cc, 9.4:1 @ 68cc, File-Fit Rings, H Bearings

Part Number: SUM-R5836L9037

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Pro LS 4340 Rotating Assembly, 377 Cid., 4.070 bore, 3.622 stroke, 58x, 6.125 rod, 2cc dome, 11.6:1 @ 65cc, 11:1 @ 70cc, File-Fit Rings, H Bearings

Part Number: SUM-R5836L0702

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Pro LS 4340 Rotating Assembly, 347 Cid., 3.903 bore, 3.622 stroke, 24X, 6.125 rod, 3cc dome, 11:1 @ 65cc, 10.6:1 @ 68cc, File-Fit Rings, H Bearings

Part Number: SUM-R2436L9033

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Cylinder Kit, Forged Piston, 2.00mm Oversize Bore, KTM, 13.50 to 1 Compression Ratio, Kit

Part Number: CLW-50001-K01

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Estimated Ship Date: Apr 13, 2026 if ordered today

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Cylinder Kit, Forged Aluminum, 3.20mm Oversize Bore, for use on Honda®, Set

Part Number: CLW-11007-K01

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Estimated Ship Date: Apr 13, 2026 if ordered today

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STD BORE KIT HI COMP

Part Number: CLW-20002-K03HC

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Estimated Ship Date: Apr 13, 2026 if ordered today

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Big Bore Cylinder Kit, Forged Piston, 80mm Bore, Yamaha, Motorcycle, Kit

Part Number: CLW-21002-K01

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Estimated Ship Date: Apr 13, 2026 if ordered today

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Cylinder Kit, Aluminum, 45.00mm Bore, KTM, Set

Part Number: CLW-50005

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Estimated Ship Date: Apr 13, 2026 if ordered today

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STD BORE KIT

Part Number: CLW-10004-K02

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Estimated Ship Date: Apr 13, 2026 if ordered today

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