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RZR800 RZR 800 Big Bore Kit Rebuilt Motor Engine Rebuild Kit Complete 83 mil 820

$1,699.99

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Compatible Vehicles
Submodel Year Make Model
LE EPS 2014 Polaris RZR 4 800
-- 2013 Polaris RZR 4 800
LE EPS 2013 Polaris RZR 4 800
-- 2012 Polaris RZR 4 800
Robby Gordon Edition 2012 Polaris RZR 4 800
Robby Gordon Edition EPS 2012 Polaris RZR 4 800
Robby Gordon Edition 2011 Polaris RZR 4 800
Robby Gordon Edition EPS 2011 Polaris RZR 4 800
Robby Gordon Edition 2010 Polaris RZR 4 800
-- 2014 Polaris RZR 800
LE EPS 2014 Polaris RZR 800
Pursuit 2014 Polaris RZR 800
Walker Evans EPS 2014 Polaris RZR 800
XC Edition 2014 Polaris RZR 800
EFI 2013 Polaris RZR 800
LE EFI 2013 Polaris RZR 800
LE EFI EPS 2013 Polaris RZR 800
Pursuit 2013 Polaris RZR 800
EFI 2012 Polaris RZR 800
EFI EPS 2012 Polaris RZR 800
EFI LE 2012 Polaris RZR 800
EFI LE EPS 2012 Polaris RZR 800
Walker Evans Edition EFI 2012 Polaris RZR 800
EFI 2011 Polaris RZR 800
EFI EPS 2011 Polaris RZR 800
Pursuit EFI 2011 Polaris RZR 800
EFI 2010 Polaris RZR 800
EFI EPS 2010 Polaris RZR 800
Walker Evans Edition EFI 2010 Polaris RZR 800
EFI 2009 Polaris RZR 800
LE 2009 Polaris RZR 800
EFI 2008 Polaris RZR 800
Military 2009 Polaris RZR S
-- 2014 Polaris RZR S 800
LE EPS 2014 Polaris RZR S 800
EFI 2013 Polaris RZR S 800
LE EFI 2013 Polaris RZR S 800
LE EFI EPS 2013 Polaris RZR S 800
EFI 2012 Polaris RZR S 800
LE EFI 2012 Polaris RZR S 800
EFI 2011 Polaris RZR S 800
EFI 2010 Polaris RZR S 800
LE EFI 2010 Polaris RZR S 800
EFI 2009 Polaris RZR S 800
6x6 EFI 2014 Polaris Sportsman 800
6x6 Forest 2014 Polaris Sportsman 800
EFI 2014 Polaris Sportsman 800
Forest 2014 Polaris Sportsman 800
6x6 EFI 2013 Polaris Sportsman 800
6x6 Forest 2013 Polaris Sportsman 800
EFI 2013 Polaris Sportsman 800
Forest 2013 Polaris Sportsman 800
6x6 EFI 2012 Polaris Sportsman 800
6x6 Forest 2012 Polaris Sportsman 800
EFI 2012 Polaris Sportsman 800
Forest 2012 Polaris Sportsman 800
6x6 EFI 2011 Polaris Sportsman 800
EFI 2011 Polaris Sportsman 800
6x6 EFI 2010 Polaris Sportsman 800
EFI HO 2010 Polaris Sportsman 800
6x6 EFI 2009 Polaris Sportsman 800
EFI 2009 Polaris Sportsman 800
HO EFI 2009 Polaris Sportsman 800
Touring EFI 2009 Polaris Sportsman 800
EFI 2008 Polaris Sportsman 800
EFI Military HO 2008 Polaris Sportsman 800
Touring EFI 2008 Polaris Sportsman 800
-- 2007 Polaris Sportsman 800
Deluxe EFI 2007 Polaris Sportsman 800
EFI 2007 Polaris Sportsman 800
Twin Browning EFI 2006 Polaris Sportsman 800
Twin EFI 2006 Polaris Sportsman 800
Twin EFI 2005 Polaris Sportsman 800
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FITS ALL POLARIS RZR AND SPORTSMAN 800 YEARS AND MODELS! 

  • 83mm big bore cylinder 
  • CP or JE forged hi comp pump gas pistons**
  • Nitrite coated piston rings
  • Chrome wristpins
  • Circlips  
  • Hotrods HD crank with rods assembled
  • MAXLOCK head stud kit
  • Improved 4135 heat treated alloy steel
  • Rolled threads and black oxide rust proof coating
  • 12 point flange nuts and washers
  • LIFETIME WARRANTY ON STUDS*!
  • Crank roller bearings
  • Crank plane bearings/bushings
  • Counter balancer bushings
  • Complete gasket kit
  • Cometic MLS big bore head gasket
  • Seal kit
  • Kibblewhite viton valve stem seals
  • Water pump mechanical seal
  • Water pump bearing, cover oring
  • Stickers

Pistons use pump or race gas.  

Everything is new in the original packaging.  We are an authorized distributor and the original manufacturer’s warranty applies*.  PRICES AND LISTINGS ARE SUBJECT TO CHANGE AT ANY TIME WITHOUT NOTICE.

Visit us online or in person from 7am to 4pm at 1538 Howard Access Rd, Suite A, Upland, CA 91786

Payments:  We accept all forms of payment – Cash, MC, AMEX, VISA, DISC, PayPal, Venmo, Cash App, among others.  Payment can be made online or over the phone or in person. 

Returns: Returns are accepted within the first 30 days as long as the order is sent back to us BRAND NEW, NEVER INSTALLED, 100% COMPLETE, AND IN THE ORIGINAL PACAKGING.  Any item returned after installation is not eligible for a refund.

 *Warranty:  This product is NOT DIY.  Over 99% of people in the world are not qualified to build an engine.  We ALWAYS STRONGLY recommend parts be installed by a qualified, experienced mechanic.  Warranty does not cover failure that is a result of improper installation, tuning, break in, or misuse.  For any warranty to be considered the part(s) in question must first be sent back to us for inspection.  We do not warranty parts based on phone calls, photos, emails, or another mechanic's assessment alone.  It is the responsibility of the person assembling and tuning the parts to make sure they work correctly. 

STUD WARRANTY: If for any reason a stud fails during use, not installation, we will send an entire new stud kit.  No other parts or any labor are included, and it can not be converted to a refund or discount on any order.  Studs must be returned to us for inspection first. 

ALPHA CUB WARRANTY: If your Alpha Cub cylinder fails for any reason not related to installation, tuning, break in, or misuse we will fix the cylinder free of charge.  If it can not be fixed we will supply you with a new one.  It must be sent to us for inspection, and Millennium Technologies will determine if the cylinder is repairable.  WE DO NOT WARRANTY ANYTHING BASED ON WHAT ANOTHER MECHANIC SAYS IS THE PROBLEM.

Feedback: Positive reviews and feedback are greatly appreciated.  We have changed the way we do business in response to customer concerns and receiving positive feedback when an order goes the way it is supposed to is a huge help.  If you do not feel we deserve positive feedback or reviews just contact us and we will do what is needed to help you feel as "positive" as possible about your experience.  To make it worth your while we will give you 10% off your next order for taking the time to leave us 5-star positive feedback.  That could be hundreds or dollars for 1 minute of your time!