These high compression 3-1/2" bore forged stroker pistons for 1984-'99 HD® big twins are a high compression option for 89" stroker kits for 1984-'99 with 4-5/8" stroke flywheels and S&S® Super Stock heads. 12:1 compression .
These pistons may also be used in stock stroke 1200cc HD® Sportster® models with S&S® Super Stock heads.10:1 compression.
+.020" oversize.
Recommended Piston Fitment: Close .0020"-.0025" Loose .0030"-.0035"
Cylinders in 1986-'03 883cc HD® Sportster® Models may be bored from the stock 3" bore to 3-1/2" for these pistons.