HAMMER PERFORMANCE - High Performance for your Harley Twin Cam, Evo Big Twin, Sportster or Buell! Why Settle for a 1250?
Go Big or Go Home! Our 1275 Kits let you take your Sportster or Buell XB12 out to 1275cc with no case boring required.
It's a bolt-on kit that can be installed in an afternoon without removing your engine from the frame! Each kit comes standard with the best components on the market. Sledge Hammer 3.600 Bore Steel Lined Aluminum Cylinders.
In the 86-03 small fin style and your choice of Black, Silver, or Black with Highlighted Fins (specify color at checkout). Sledge Hammer 3.600 Bore Forged Pistons. In your choice of dome configurations to match your heads.Lightweight Tool Steel Wrist Pins. Premium Quality Moly Faced Rings. 030 Multilayer Steel Head Gaskets and. 020 Coated Steel Base Gaskets (upgrade to a full Cometic top end set available). Installation is easy with our detailed illustrated instructions! From Hammer Performance are the result of over a decade of experience with 1250 kits. We've seen what works and what doesn't, and none of the offerings on the market really solved all the issues we came across, so we set out to make a cylinder that combines the best features of all of them. We're proud to bring you these fine cylinders, which we believe to be the best ones available for a street application. Ring seal depends on a straight and round bore, and this is the main objective in any cylinder design. Under the extreme pressure and heat of a high performance engine, cylinders want to grow, twist and distort, and that makes it impossible for the rings to stay sealed. We've seen some cylinders that grow and distort so badly that head bolts break, cylinder studs pull out of the cases, and head gaskets blow. For the straightest and roundest bore possible under these extreme conditions, coupled with the ability to shed heat and keep the engine cool, Sledge Hammer 1275 cylinders utilize an aluminum finned construction with an extra thick hard steel liner that stays straight and true.
The end result for you is a lightweight, cool cylinder with superb ring seal for less oil consumption, less blow-by, and more power. Please Note: This listing is for 1275 kits using the small fin style as shown on the left in the picture above. If you have a 2004 or newer Sportster or Buell, the correct fin pattern is the style shown on the right, which is available in this listing. These small fin 86-03 style cylinders will fit on 04-up models if you grind off the lowest fin on the pushrod side, however, we don't recommend this, as by reducing fin size you'll lose cooling capability as well as compromise the appearance with mismatched fins between the cylinders and heads.
Conversely, the large fin 2004-up style cylinders. So how did we achieve 1275cc when everyone else only has a 1250?
The secret is our 120,000 psi tensile strength steel liner. This liner enables a thinner spigot as shown on the left above, which allows for a bigger bore without case boring. But the working area of the cylinder (right) remains thick to promote good ring seal. Before introducing the 1275, we tested these cylinders for a year in the most brutal street and strip applications.
We're pleased and proud to now offer these to the market. So how much power is this cylinder capable of supporting? Take a look at this actual result.
This 1275 result came from our 120+hp bolt-on package. Remember, this is a bolt-on kit that requires no case boring for installation! Maintain Your Engine's Proper Appearance! One of our competitors doesn't even offer their kits in black highlighted.
Another just hits the fin edges with a sander and gets the look shown on the left above. HAMMER PERFORMANCE takes the extra time to CNC machine the fins on black highlighted cylinders.
This maintains the proper appearance to match the factory black highlighted heads. Don't settle for less, get the best, HAMMER PERFORMANCE! Complementing these great cylinders is a set of our exclusive forged Sledge Hammer Pistons. These pistons are lighter than the competition's for more power and less vibration, and they're actually stronger as well. They feature extra large valve pockets for those radical cams, anti-detonation grooves, dual wrist pin oilers, expansion grooves for superior ring seal, and ribbing to give maximum strength with minimum weight.
You cannot find a finer piston for your HD or Buell. So Just How Much Lighter is a Sledge Hammer Piston? Here's a side by side comparison of a conventional forging 1250 kit 15 degree piston and the SLEDGE HAMMER 15 degree 1250 kit piston. Less weight means less vibration, less wear and tear on the lower end, and more power!
Use the best, SLEDGE HAMMER pistons from HAMMER PERFORMANCE! Trick New 30 Degree Reverse Dome Piston Now Available!
Looking for the ultimate in chamber efficiency? It's well known that 30 degree dome angles work the best; they give maximum chamber unshrouding and also direct the fuel coming out of the squish band more directly at the flame front. But the problem has always been that they give up squish band surface area unless the dome is made really tall, which of course cranks up the compression. For this reason, 30 degree pistons have largely been limited to race-only applications. We've combined a tall 30 degree dome, providing lots of squish area, with a dish in the middle to drop the dome volume down to pump-gas friendly levels.
The result is what you see here, an ultra-trick 30 degree reverse dome piston suitable for street motors! No longer do you have to compromise on the dome angle to use pump gas! These pistons are now available as a standard offering in the HAMMER PERFORMANCE Bolt-On 1275 kits. Please Note: 30 degree pistons require a matching 30 degree squish band be machined in the chamber.
HAMMER PERFORMANCE can handle this service for you. We machine all chambers by CNC and they come out a perfect match for the piston every time. GET A 1275 KIT FROM HAMMER PERFORMANCE! Please note that if you'll be running factory stock cams, you'll need to limit your compression to 10:1 or less to avoid detonation.
The one exception to this is certain Buell models that came from the factory with SE bolt-in. 497 lift cams (S1, S1W, S3/S3T, X1, and International M2 models), as well as all Buell XB models. These are okay at 10.5:1 compression.
If you're not sure what pistons you need, let us know the year of your bike, whether it's a native 883 or 1200, what type heads are going to be used with it, and what cams you'll be using. We'll select the appropriate pistons for your application. Hammer Performance 1275 Kits for Sportsters & Buells. 88-03 XL1200 95-96 Buell S2.
98-03 XL1200S 96-03 SE/Lightning 96-98 Buell S1 97 Buell S3 97-98 Buell M2 (Lightning Heads). 98 Buell S1W & S3 99-02 Buell all. 86-87 XL1100 04-present XL1200 04-present SE 04-10 Buell XB12. Machine for Desired CR Note 2. Note 1: 30 degree dome angles provide the optimum chamber efficiency but require the cylinder heads be machined to match.Note 2: the 30 degree x. 500 dome race pistons are designed to be cut down to achieve your desired compression ratio, call for details. OPTIONS TO MAKE THESE KITS EVEN BETTER. For the ultimate in convenience, add our pre-assembly option. This service makes the installation a breeze, as you simply lower the piston down enough in the bore to expose the wrist pin hole, position it over the connecting rod, insert the wrist pin and circlip, and push the cylinder down into position. Another popular option is to upgrade the included head and base gaskets to a Cometic full top end gasket set. Gap Rings and Pre-Assemble Engine Kit.
Upgrade Head & Base Gasket to Full Cometic Top End Gasket Set. The Cometic Extreme Sealing Technology (EST) top end gasket set is a premium gasket set with every gasket you'll encounter during the 1250 kit installation.HAMMER PERFORMANCE has put together a tech article to tell you all about converting your 883 to a 1275. Give it a read here. It lays out what you need for anywhere from a basic conversion.. Actual Dyno Result from an otherwise stock 2004 883 converted to a 1250 The 1275 makes an additional 2-3% more power all else equal.
All the way up to a powerhouse of a conversion.. HAMMER PERFORMANCE has the technology, experience, and proven track record of making big results like this.
Don't settle for second best, hit it with a HAMMER! Can this kit be installed on an 883 with stock heads and no machine work or balancing?
In the application table above, the very first piston listed is made for use with stock 883 heads. Is anything else needed to install this kit? Yes, you will probably need some other things depending on the year and model of your Sportster.The correct jets are available from HAMMER PERFORMANCE. 2004+ 883 models need a clutch spring upgrade. Read more about this here.
2007+ models will need a suitable flash tuner device to adjust both fueling and ignition timing. Read about suitable tuner devices here.Please Read BEFORE You Order! We need some specific information before we can fill your order.
You can help us out and eliminate a lot of back and forth if you provide this info at the time you place the order. What year is your Sportster?Is it a native 883 or 1200? What color cylinders do you want? Silver, black, or black with highlighted fins? Which pistons do you need? If you're not sure, let us know what type of cylinder heads you'll be using and also what cams and we'll make sure you get the right pistons. This has all of the gaskets and seals you need for the entire top end, including rocker box, head, base, intake, exhaust, and pushrod covers. We precision gap your rings and assemble the pistons and rings into the cylinders for you.
They will arrive pre-lubed and ready to install per our kit installation instructions. This service eliminates the most tedious and error prone part of the kit installation.
Over 95% of our customers choose this option, and of the few who don't, probably half of them end up ordering a replacement set of rings because they botched the job. You can do it successfully, though, if you're careful and patient. Our kit installation instructions go over the procedures. The invoice will cover the cost of the upgrades. Please help us help you and provide the information at the time of your order.
The item "HAMMER Bolt-On 1275 Kit for 1986-2003 Harley Sportster Why Settle for a 1250" is in sale since Friday, April 10, 2015. This item is in the category "eBay Motors\Parts & Accessories\Motorcycle Parts\Engines & Engine Parts\Big Bore & Top End Kits". The seller is "hammerperf" and is located in Sandpoint, Idaho. This item can be shipped worldwide.