2012 Engine Kits & Rotating Assemblies

Pro LS 4340 Piston and Rod Kit, 378 Cid., 4.075 bore, 3.622 stroke, 6.125 rod, 12cc dish, 9.9:1 @ 65cc, 9.4:1 @ 70cc, File-Fit Rings

Part Number: SUM-PR36L08012

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Estimated Ship Date: Monday 2/2/2026

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Pro LS 4340 Rotating Assembly, 364 Cid., 4.000 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-R583600012

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Estimated Ship Date: Monday 2/2/2026

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 2/2/2026

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 2/2/2026

Pro LS 4340 Rotating Assembly, 371 Cid., 4.040 bore, 3.622 stroke, 58x, 6.098 rod, 12cc dish, 9.8:1 @ 65cc, 9.3:1 @ 70cc, File-Fit Rings, H Bearings

Part Number: SUM-R583604012

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Estimated Ship Date: Monday 2/2/2026

Pro LS Rotating Assembly, 371 Cid., 4.040 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-R58360402

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Estimated Ship Date: Monday 2/2/2026

Pro LS 4340 Rotating Assembly, 417 Cid., 4.080 bore, 4.000 stroke, 24X, 6.125 rod, 6cc dish, 11.6:1 @ 65cc, 11:1 @ 70cc, File-Fit Rings, H Bearings

Part Number: SUM-R24400806

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Estimated Ship Date: Monday 2/2/2026

Pro LS 4340 Rotating Assembly, 359 Cid., 3.780 bore, 4.000 stroke, 24X, 6.125 rod, 5cc dish, 10.9:1 @ 61cc, 10.4:1 @ 65cc, File-Fit Rings, H Bearings

Part Number: SUM-R24407805

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Estimated Ship Date: Monday 2/2/2026

Pro LS Rotating Assembly, 371 Cid., 4.040 bore, 3.622 stroke, 24X, 6.125 rod, 2cc Flat Top, 10.9:1 @ 65cc, 10.3:1 @ 70cc, File-Fit rings, H Bearings

Part Number: SUM-R2436L0402

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Estimated Ship Date: Monday 2/2/2026

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 2/2/2026

Pro LS 4340 Rotating Assembly, 376 Cid., 4.065 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-R2436L0652

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Estimated Ship Date: Monday 2/2/2026

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 2/2/2026

Pro LS 4340 Rotating Assembly, 377 Cid., 4.075 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-R2436L07512

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Estimated Ship Date: Monday 2/2/2026

Pro LS 4340 Rotating Assembly, 377 Cid., 4.075 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-R2436L0752

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Estimated Ship Date: Monday 2/2/2026

Pro LS 4340 Rotating Assembly, 378 Cid., 4.080 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-R2436L08012

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Estimated Ship Date: Monday 2/2/2026

Pro LS 4340 Rotating Assembly, 378 Cid., 4.080 bore, 3.622 stroke, 24X, 6.125 rod, 2cc dome, 11.6:1 @ 65cc, 11:1 @ 70cc, File-Fit Rings, H Bearings

Part Number: SUM-R2436L0802

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Estimated Ship Date: Monday 2/2/2026

Repair Kit, Top End, 68.45mm Bore, 9.50 to 1 Compression Ratio, for use on Honda®, Kit

Part Number: NTI-NA-10027K

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Estimated Ship Date: Feb 23, 2026 if ordered today

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Repair Kit, Top End, 83.000mm Bore, 8.60 to 1 Compression Ratio, Yamaha, Kit

Part Number: NTI-NA-40006K

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Estimated Ship Date: Feb 23, 2026 if ordered today

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TOP END REPAIR KIT

Part Number: NTI-NX-40005-4K

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Estimated Ship Date: Feb 23, 2026 if ordered today

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Rebuild Kit, Complete Bottom End, for use on Honda®, CRF450R, Kit

Part Number: HRI-CBK0124

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Estimated Ship Date: Feb 16, 2026 if ordered today

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STD BORE KIT

Part Number: CLW-10004-K02

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Estimated Ship Date: Feb 23, 2026 if ordered today

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Top End Engine Kits STANDARD BORE KIT STANDARD BORE KIT

Part Number: CLW-60001-K01

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Estimated Ship Date: Feb 23, 2026 if ordered today

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Rebuild Kit, Complete Bottom End, KTM, 144 SX, 150 SX, 150 XC, Kit

Part Number: HRI-CBK0063

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Estimated Ship Date: Feb 16, 2026 if ordered today

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Rebuild Kit, Complete Bottom End, KTM, 65 SX, 65 XC, Kit

Part Number: HRI-CBK0073

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Estimated Ship Date: Feb 16, 2026 if ordered today

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BOTTOM END KIT Polaris

Part Number: HRI-HR00113

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Estimated Ship Date: Feb 16, 2026 if ordered today

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