Cylinders & Pistons

158 products

Shop the range of aftermarket motorcycle engine products at Pro Class Custom Parts.

$596.99

Features & Benefits:- * Bore = 3.508″ * Stroke = 3.812″ * Hypereutectic Alloy is a cast 16% silicon content material. * Perfect for air cooled engines. * Low thermal expansion rate = tighter p...

FEULING

$340.99

* The strongest studs available! * Top engine builders demand quality fasteners! Secure your engine with complete confidence * Superior in strength and performance to any other cylinder stud kit o...

$321.99

Features & Benefits:- * Crafted from strong, billet 6061 T6 aluminum * Patent Pending Dual Spray Technology for uniform piston cooling * Revised spray locations for more effective cooling * An...

COLONY MACHINE

$244.99

* Set of 8 * Replaces OEM # 16837-85 MFR PART No: 9424-8 ROLLIES PART No: CM-9424-8

$4,711.99

Features & Benefits:- * 80ci with High Compression. * 4-1/4″ Stroke. * 3-1/2″ Bore. * 5.330″ Cylinder Length. * 9.0:1 Compression. * Includes Cylinders, Piston Kit, Head Bolts, Base Nuts &...

$4,714.99

Features & Benefits:- * 74ci with High Compression. * 3-31/32″ Stroke. * 3-7/16″ Bore. * 5.330″ Cylinder Length. * 9.0:1 Compression * Includes Cylinders, Piston Kit, Head Bolts, Base Nuts &am...

136ci Stroker Big Bore Kit with Highlighted Fins – Black. Fits Milwaukee-Eight 2017up with S&S 4-5/8in. Stroker Flywheel.

$3,906.99

S&S has been building big bore kits since the 60s and has it down to an absolute science. Our latest efforts are aimed at the Milwaukee Eight® platform and open up a whole new level of perform...

136ci Stroker Big Bore Kit with Non-Highlighted Fins – Black. Fits Milwaukee-Eight 2017up with S&S 4-5/8in. Stroker Flywheel.

$3,906.99

S&S has been building big bore kits since the 60s and has it down to an absolute science. Our latest efforts are aimed at the Milwaukee Eight® platform and open up a whole new level of perform...

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132ci Big Bore Kit with Highlighted Fins – Black Granite. Fits CVO Milwaukee-Eight 2017up with 117ci Engine.

$3,722.99

Features & Benefits:- * Upgrades Milwaukee-Eight 117ci CVO models to 132ci * 4.320″ Bore * 4.500″ Stroke (4-1/2″) * Forged Pistons. * 11.1 Compression Ratio. * Black Granite Finish With Highl...

$3,188.99

Features & Benefits:- * Includes Cast Flat Top Pistons. * Includes Gaskets. * 8.5:1 Compression Ratio with Stock HD Heads. * 8.8:1 Compression Ratio with S&S 76cc Performance Heads # SS106...

129ci Big Bore Kit with Highlighted Fins – Black. Fits Milwaukee-Eight 2017up with 107ci Engine.

$3,725.99

Features & Benefits:- * Upgrades Milwaukee-Eight 107ci to 129ci. * 4.320″ Bore. * 4.375″ Stroke (4-3/8″). * Forged Pistons. * 11.1 Compression Ratio. * Wrinkle Black Finish. * With Highlighted...

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128ci Big Bore Kit with Highlighted Fins – Black. Fits Milwaukee-Eight 2017up 114ci Engine.

$3,722.99

Features & Benefits:- * Upgrades Milwaukee-Eight 114ci to 128ci * 114ci to 128ci Big Bore Kit * 4.250″ Bore * 4.500″ Stroke (4-1/2″) * Forged Pistons. * 11.1 Compression Ratio. * Wrinkle Blac...

132ci Big Bore Kit with Non-Highlighted Fins – Black. Fits Milwaukee-Eight 2017up 114ci or 117ci Engine.

$3,725.99

Features & Benefits:- * Upgrades Milwaukee-Eight 114ci & non-CVO 117ci to 132ci * 4.320″ Bore. * 4.500″ Stroke (4-1/2″). * Forged Pistons. * 11.1 Compression Ratio. * Wrinkle Black Finish...

129ci Big Bore Kit with Non-Highlighted Fins – Black. Fits Milwaukee-Eight 2017up with 107ci Engine.

$3,725.99

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1200cc Big Bore Kit – Silver. Fits Sportster 1986-2021 with 883cc Engine.

$2,677.99

Features & Benefits:- * Will Not Fit XR1200 * Includes silver cylinders. * Includes MLS Head Gaskets, Base Gaskets & Exhaust Gaskets. * Includes assembly lube & instructions. * No mac...