THE BEST VALUE GOING - STAGE 1 CNC HEAD PORTING SERVICE

ONLY $550.00!

This service includes a full state-of-the-art CNC porting job to reshape and resize your ports for a dramatic improvement in flow while maintaining high air speed for that arm jerking torque. The CNC process ensures a level of quality and repeatability simply not possible with a hand porting process. To complement these ports, your stock valves are refaced and trued up and mated to an NRHS proprietary radius valve job for optimum flow and valve seal. The head surface area is then flat-milled to ensure an absolutely flat gasket surface and to correct for the small amount of volume added by the valve job. Your stock springs are carefully tested for pressure and travel. The heads are then  thoroughly cleaned and assembled with all valve spring installed heights set for proper seat pressure. Finally, every set of Stage 1 heads is flow bench tested to ensure that the front and rear flow numbers are correct and properly balanced, and all parameters of the head are carefully documented. The end result is a high quality pair of heads that will deliver great performance without costing you a fortune!

Since they use the stock springs, Stage 1 heads are best suited for use with "bolt-in" style cams. Please call NRHS for recommendations.

Performance tip: The  XB9/XB12 and 2004 XL1200R heads are the best performing OEM heads NRHS has ever tested, exceeding even the popular "Thunderstorm" factory high performance head. Read more about these exciting new heads here.

Like the Stage 1 service, the Stage 2 service includes porting on a state-of-the-art CNC machine to ensure a quality and performance level simply not achievable with hand porting. But Stage 2 also includes all new premium quality Hurricane stainless valves, high performance springs, titanium retainers, 10 degree locks, and bronze manganese valve guides!. The valves are oversize as well to increase flow and cylinder fill:  1.760/1.530 sizes for 91-03 XL & Blast heads, or 1.850/1.615 valves for Thunderstorm, XB, and 2004 XL heads. These larger valves are designed for maximum flow while maintaining excellent velocity, which is absolutely key to making big power over a wide rpm range. In fact, a Stage 2 head will generally produce more power over the entire rpm range than a Stage 1 head (assuming matching components), not just high rpm! The NRHS Hurricane springs with titanium retainers and 10-degree locks will accept cam lifts up to .600" lift (higher lift capacity springs available upon request for no extra charge).  These heads are a popular choice because of their versatility to be utilized in both mild and wild combinations. The premium hardware and oversize valves to complement the CNC port work makes them a terrific value as well. All of the careful documentation that goes into a Stage 1 head in regards to assembly and overall airflow balance also pertains to a Stage 2 head.

Stage 2 light now available!!

NRHS is proud to announce our newest stage of headwork,  We call it stage 2 light.  You still get the same great CNC porting that our regular stage 2 kits come with plus our stainless Hurricane 7mm valves in 1.840 Intake and 1.615 exhaust sizes.  But we have found that when using cams with lifts of .550 or less that the new beehive spring kits from HD work excellent.  By using these springs you not only save money but also eliminate the need for rocker box clearancing and put less strain on the valvetrain components.  The perfect choice for cams such as SE 551, SE536 and Andrews N4s.  Available for XB, 04 1200 and Thunderstorm head

                                          Stage 2 Standard

Maximum cylinder fill is the name of the game when it comes to making power, and that means a precise balance between flow and velocity. But to strike that balance perfectly requires custom tailoring the port volume and cross sectional are to the engine's airflow requirements as well as cam timing. Enter the NRHS Stage 3 CNC-FLEX treatment. We take the specifications of your engine and intended torque peak rpm, process them through some proprietary software, and send the result to the CNC machine where the port is cut perfectly to size for your application, far more precisely than any human with a die grinder can hope to achieve. The result will astonish you; using this process we have literally produced over 124rwhp and 97 lb/ft of torque on 1250cc motors, and over 130rwhp and 110 lb/ft of torque on 88" motors! And that's on street bikes that run pump gas.

Like the Stage 2 service, Stage 3 includes premium NRHS Hurricane valvetrain components: bronze manganese guides, high flow stainless valves, chrome silicone springs, and special radius titanium retainers. The valve sizes are custom tailored to the application, and may include all the way up to 1.900" intake and 1.615" exhaust valves (note that 1.900" intake valves in a 3.5" bore requires careful checking of valve to piston clearance). Valve to valve clearance is set for your particular cam choice and the valves are unshrouded as needed to maximize low lift flow. Chamber work and cutting of the deck and/or squish band for your particular pistons and desired compression ratio is also included at Stage 3 at no extra charge. A set of NRHS Hurricane .600, .650, or .700 lift springs will be selected depending on the cams being used and the target rpm peak. The Stage 3 head is truly a custom tailored head in every way, designed to get you everything out of your heads possible. It's totally at home on the track or on the street. If you want it all, go with the proven performer, Stage 3 heads from NRHS!

Note: We also have extensive experience at porting heads from STD, S&S, and others, and we can provide new castings as needed for all major brands.  Please call for details

The top of the line! These Stage 3 XL1200R heads have been cut

with a 30 degree angled squish band for special application

racing pistons. The extra-large 1.900" intake valves have been

heavily unshrouded for maximum flow, and the 30 degree angle

complements this nicely by reducing even further the shelf that

the air must go around to fill the cylinder. The 30 degree angle

is recommended for higher compression, higher dome pistons as

commonly used in racing or very hot street applications. For moderate

dome heights as found in most street applications, the 15 degree angle

(i.e. Thunderstorm type pistons) provides more squish area thus

increasing chamber turbulence and reducing detonation.

These mounts were designed to be an extra-strong replacement for the failure prone factory mount. Extra material was placed in all of the stressed locations and all corners are radiused to eliminate stress risers. Furthermore, special attention was paid to the ease of installation. Unlike some other aftermarket mounts, this mount can be installed like the factory mount, without removing the gas tank and the rubber isolator, because the bolt can be inserted from the bottom. And not only are they strong, they're beautiful as well!

NRHS Exclusive! We are now offering a version of this mount that adapts XB cylinder heads to 1995-2002 model Buells! XB cylinder heads are rapidly becoming the high performance head of choice in XL and Buell applications due to their superior port shape and small chamber that nets 10:1 with flat tops. This mount overcomes the major hurdle to installing XB heads on tube frame Buell models. Shipping now!