S&S, forged 3-5/8" big bore piston kit. +.020"

Description

Fits all 3-5/8" big bore 36-84 B.T. models with 4-1/4" to 5" stroke flywheels with the correct flywheel diameter of 8-1/2. Note that 4-3/4" & 5" strokes require 8-1/4 small diameter flywheels, all in combination with the appropriate cylinder length like mentioned below. Advanced alloy and piston skirt profile is used for low noise and long engine life. Piston dome volume 30cc, piston deck height 1.260".

88" (4-1/4" stroke, 8-1/2" flywheel dia., 8.5:1 CR, 5.330" cyl. length).

93" (4-1/2" stroke, 8-1/2" flywheel dia., 8.5:1 CR, 5.405" cyl. length).

93" HC (4-1/2" stroke, 8-1/2" flywheel dia., 9.1:1 CR, 5.363" cyl. length).

96" (4-5/8" stroke, 8-1/2" flywheel dia., 9.1:1 CR, 5.440" cyl.length).

98" (4-3/4" stroke, 8-1/4" flywheel dia., 8.9:1 CR, 5.530" cyl. length).

103" (5" stroke, 8-1/4" flywheel dia., 9.7:1, 5.630" cylinder length).

Pistons include wrist pins, wrist pin clips and piston rings.



Note: For a higher compression ratio S&S advises shortening the cylinders. Shortening cyl. .060" will produce approx. 1 point increase in CR.

Note: In any and all applications the technician must be able to judge components for their suitability in combination with the other engine components, prior to installation. It is of importance that a knowledgeable mechanic will install & make adjustments as required. The rider must follow standard break-in and riding procedures for overhauled engines.

Specifications

Fitment

36-84 88", 93", 93"HC, 96", 98" and 103" Big Twin with appropriate cylinders and flywheel stroke (NU)

Part numbers