S&S Cycle offers engine kits for your Harley-Davidson® bit twin or Sportster® motorcycles. Increase your horsepower with these engine kits that increase your displacement and don't let sleeping hogs lie.
No need to bore or even split the cases, just do the cylinder and piston swap. In addition to the ease of installation, they look great because the cylinders are available with the same silver or wrinkle black powdercoat as stock, so they match the stock finish of your engine.
1250cc Conversion Kits for 1986-2014 1200cc Harley-Davidson® Sportster® Models
When it comes to big bore kits, the bigger the better. That’s the idea behind S&S Cycle’s new 98” and 107” bolt-in big bore kits. S&S has offered 97” and 106” kits for a while, but these new kits are bigger. Aside from the additional cubic inch of displacement, the new 98” and 107” kits are better for a couple of other reasons. The pistons are one reason. Both the 98” pistons and the 107” pistons are made by CP Pistons, and feature pop-up domes to increase compression. The 98” piston has a 10cc pop-up and the 107” piston has a 3cc pop-up. We increased the squeeze a little because most performance cams just work better with a bit more compression. But the pistons have another great feature. They can be used in stock cylinders that have been bored out to the required 3.937” bore size. That could save you some money, but… Why would you buy the complete big bore kit from S&S rather than just get the pistons and bore your stock cylinders? There are several good reasons. Quality, convenience, and Proven Performance®. S&S cylinders are made from superior materials and machined to exacting standards. They come with the pistons fit and ready to install. The kit has everything you need so your engine can be upgraded in an afternoon instead of waiting days or weeks for a machine shop to bore your stock cylinders - less down time. Proven Performance is self-explanatory. All S&S products are backed by our 55+ years experience in making Harley-Davidson® motorcycles go faster.
S&S 117" Big Bore Cylinder and Piston Kit in Stone Gray