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S&S Cycle 883cc To 1200cc Conversion Kit For Harley Sportster
Maybe you need more power from your 883. Maybe you're a handy type who realized he could buy an 883 and a big-bore kit cheaper than he could buy a 1200 Sportster. Whatever the reason you're contemplating enlarging your engine, know that S&S has got you covered with a high-quality kit that makes the job a snap.
Increases displacement from 883cc to 1200cc
Save time because pistons are already fit to the cylinders - they're ready to assemble right out of the box
No re-balancing of your 883cc flywheels
No cylinder head modifications
Available in wrinkle black and silver powdercoat finish
Big bore 3 1/2" cylinders
9.6:1 compression ratio with stock 883cc heads
Kits include cylinders, pistons, rings and gaskets (head, base and exhaust)
Have a functionality, fit, or otherwise product-specific question about the S&S 883 To 1200cc Conversion Kit For Harley Sportster 1986-2015? Ask it here!
If you have a customer service or shipping question, please direct it to our Customer Service department.
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A shopper asked:The notes at the bottom of the big bore kit upgrade state that you will need to buy rocker box cover, carb, and intake gaskets. THe Gaskets are listed with the kit description, are those the correct gaskets mentioned? What Carb part would I need? I've picked out the rockerbox cover, but the way the kit reads, are those absolutly needed? I also have a question about the Roland sands Venturi Ronin air cleaner. What adjustments will I need to make if I install that? I have never done any upgrades to a bike, but I have worked on a bike in the past, I will have knowledgeable help when doing this, I just need to know what all to buy. Thanks in advance.
A S:Roger V: The gaskets that come with the kit are base and head gaskets. Since you are removing the heads you need to remove the valve covers (rocker box) and the intake manifold and exhaust pipes therefore you will most likely need to replace all these gaskets. since you are not changing the heads you can reuse the valve covers. The carburetor will need to be rejetted or replaced since the displacement is increased and therefore the airflow. If a fuel injected biked model the ECU will need reprogramming and perhaps new higher flow injectors will be required.Oct 7, 2015
Garrett C:I asked S&S about their rocker box note at the bottom of this page. I ride a 2013 Sportster 883 Iron. They assured me that no rocker box is needed, the stock one would fit just fine. I don't know what model you ride, but I would check out the S&S website for more tech support on this.Sep 2, 2015
A S:Roger V: Ignition voltage and energy requirements are largely dictated by the density of gas in the spark plug gap and the gap distance itself. Since the compression ratio is not changing significantly and I assume you will keep the same spark plug gap no ignition system changes should be required.Oct 7, 2015