S&S CYCLE Cylinders - 4.125" - Black 910-0401 Tires Accept 3/8" rubber oil lines

Accept 3/8" rubber oil lines

Crankcases must be bored to accept the larger 3-5/8" cylinders and stock flywheel assembly should be rebalanced

625" Sidewinder

Built-in stinger cone directs air smoothly into the bore of the carburetor or EFI throttle body to reduce turbulence and increase flow

Improved horsepower and torque (when used with a Stealth Air cleaner kit

S&S CYCLE Cylinders - 4.125" - Black 910-0401 Tires Accept 3/8" rubber oil linesCylinders 4. 125" Black Cylinders have a stock bolt pattern, Bored slightly under nominal size and are not honed, Designed for 124" Hot Set Up Kits used in '99 '17 Twin Cams, Wrinkle black finish with machined edges, Made in the U. S. A., Requires crankcase machining.