Cylinder Kits

SPORTSTER & BUELL 

1991 TO PRESENT Sportster and Buells 

Cylinders

Sputhe cylinders are cast in 383 aluminum alloy, with a tensile strength of 45,000 p.s.i.  The aluminum is injected into a steel die at over 5,000 p.s.i., assuring perfect bonding to the sleeve.  Lascomite is a “class 40” high tensile chrome-moly alloy having a high molecular pearlite structure.  It is centrifugally spun cast and heat treated to a hardness of 200 Brinell.  Not only is Lascomite harder than the cast iron that Harley-Davidson and the other after-market cylinder manufacturers use, it is much tougher and less brittle.  The Lascomite sleeve in the Sputhe cylinder is 60% thicker than the sleeve in the stock Evo cylinder for increased rigidity.

The 3.780” (96mm) bore Sputhe cylinders have greater fin area and a symmetrical fin pattern that reduces thermal distortion and allows sustained operation at maximum power.  Sputhe cylinders are stock height so that the cylinder studs, pushrods, exhaust pipes, manifold and motor mounts do not need to be modified.  Heads and cylinders can be removed with the engine in the frame.

*except Buell XB-9

Part #4008A Dish Top Pistons 
Part #4008B Flat Top Pistons 

 

 

SPUTHE BIG-BORE CYLINDER KITS

Sputhe has manufactured aluminum cylinders with cast-in sleeves for Harley-Davidsons since 1977, far longer than Harley-Davidson themselves.  Our big bore cylinder assemblies for Evo Big Twins have been thoroughly tested and are manufactured from the best materials available to the most exacting standards in the industry.  Sputhe cylinders incorporate 28 unique design elements that are protected by US patent 5,072,697.

CYLINDERS

Sputhe cylinders are cast in 383 aluminum alloy, which has a tensile strength of 45,000 psi.  The aluminum is injected into a steel die at over 5,000 psi, assuring perfect bond to the Lascomite sleeve.  Lascomite is a “class 40” high tensile chrome-moly alloy having a high molecular pearlite structure.  It is centrifugally spun cast and heat treated to a hardness of 200 Brinell.  Not only is Lascomite harder than the cast iron that Harley-Davidson and other after-market cylinder manufacturers use, it is much tougher and less brittle.  The Lascomite sleeve in the Sputhe cylinder is 50% thicker than the sleeve in the stock Evo cylinder for increased rigidity.

Sputhe cylinders expand less and have better thermal dimensional stability than any iron cylinders.  The 3.780” (96 mm) bore Sputhe cylinders have a greater fin area and a symmetrical fin pattern that reduces thermal distortion and allows sustained operation at maximum power.  Sputhe cylinders are stock height so that the cylinder studs, pushrods, exhaust pipes, manifold and motor mounts do not need to be modified.  Heads and cylinders can be removed with the engine in the frame.

Part #4003S

 

Order By Phone Or Email 

E-Mail: sputhe@hotmail.com 

Tel: +1 (530) 268-0887 

PO BOX 2553

Grass Valley CA 95945

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