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S&S Cycle

S&S 1250 Big Bore Kit For Harley Sportster 1986-2021

Item: P360445
1 Read 1 Review 4 Q&As Write a Review

This kit converts 1200cc HD Sportster models to 1250cc displacement. No machining or rebalancing is required. Forged pistons have larger than stock va… Read More

$771.26
$856.95
Save $85.69 10%
Rebate Available! View Details

This product is vehicle specific.
Select a bike to ensure fitment.

Looking for a different bike? Change bike selection

Product Details

This product is legal in California only for racing vehicles which may never be used, registered or licensed for use upon a highway.

S&S 1250 Big Bore Kit For Harley Sportster 

This kit converts 1200cc HD Sportster models to 1250cc displacement. No machining or rebalancing is required. Forged pistons have larger than stock valve pockets and accept up to 2.00" valves. Kit contains forged flat topped 3 9/16" bore pistons with coated piston skirts, S&S 3-9/16" bore cylinders, MLS head gaskets, base gaskets, exhaust gaskets, assembly lube, and instructions.

Features:

  • 10.3:1 Flat Top Pistons
  • 11.2:1 5.5cc Domed Pistons
  • Available in silver powder coat or wrinkle black powder coat finish
  • Made in the USA
Made in the USA
Product Style RevZilla Item # MFR. Product # Availability
Product Style Black / 10.3:1 Compression Ratio RevZilla Item #1181564 MFR. Product #910-0443/910-0691 AvailabilityIn Stock: Ships within 24 hours
Product Style 10.3:1 Compression Ratio / Silver RevZilla Item #1181565 MFR. Product #910-0433/910-0689 AvailabilityAvailable: Requires 3-5 business days of lead time prior to shipment
Product Style Black / 11.2:1 Compression Ratio RevZilla Item #1181566 MFR. Product #910-0446/910-0692 AvailabilityIn Stock: Requires 1-2 business days of lead time prior to shipment
Product Style 11.2:1 Compression Ratio / Silver RevZilla Item #1181567 MFR. Product #910-0436/910-0690 AvailabilityAvailable: Requires 3-5 business days of lead time prior to shipment
This product is vehicle specific.
Select a bike to ensure fitment.
Fitment Notes & Exceptions
  • Will also fit 883 models with the use of XL1200 cylinder heads to achieve correct compression ratios
This Product Fits
Harley Davidson
Sportster Custom XL1200C 1996-2019
Sportster Forty-Eight Special XL1200XS 2018, 2019
Sportster Forty-Eight XL1200X 2010-2021
Sportster Low XL1200L 2006-2011
Sportster Nightster XL1200N 2007-2012
Sportster Roadster XL1200CX 2016, 2017, 2018, 2019, 2020
Sportster Roadster XL1200R 2004, 2005, 2006, 2007, 2008
Sportster Seventy-Two XL1200V 2012, 2013, 2014, 2015, 2016
Sportster Sport XL1200S 1996-2003
Sportster SuperLow XL1200T 2014, 2015, 2016, 2017
Sportster XLH1200 1988-2003
XR1200/XR1200X 2009, 2010, 2011, 2012
Product Description
Part Numbers
Fitment
1 Customer Reviews
15/5
4 Questions & 2 Answers

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