For those of you that follow the pages of dragbike you already know that Nitrous Express (nitrousexpress.com or by phone at 1-888-463-2781) has released a nitrous kit designed for the needs of the Suzuki Hayabusa. I know, I know, you are asking, "Who would possibly need nitrous on the fastest bike in the world?" Well of course the answer is you and I. By now there are all sorts of modified Busas' rolling around and if you are serious about racing you don't want to be halfway down a 1320' track in the lead only to have someone else blow by you on their nitrous bike. Trust me it is not a fun place to be. The basic purpose of this article is not to discuss if you do or do not need nitrous but to explain the general installation procedures and tips on making your nitrous installation a big success.

The good news on this install, unlike a full engine rebuild or normal performance modifications is that the engine does not have to be removed. Due to the design of the busa frame and engine, removing the head also requires removal of the engine. On this project we are going to install the nitrous with the head and engine in the frame. The only parts that have to be removed are the tank, airbox, both sides of the bodywork panels, seat and tail section if you are hiding the bottle. Our project bike here is a stock engine Busa except for a full exhaust and a DynoJet Powercommander, which is required for timing adjustments with higher hp bikes. (www.powercommander.com) If you don't already have the power commander just order it along with your nitrous kit from Stedman.

First, I want to discuss the actual Nitrous Express kit. The basic kit comes complete with everything you need for a full install. As I progress in the article you will see that I have added a few extra parts just because this was my first nitrous bike and I wanted to be extra careful to avoid any possible chance of a problem. Depending on your needs and experience in nitrous you may or may not decide to use the exact same parts as I. 

Before I began my installation I sought out the leader in the area of nitrous Busas'. In the Hayabusa world there is a man that is quickly becoming known as the expert in the field. That man is Jay Stedman, therefore I opted to buy all of my parts from Stedman Racing in Grand Rapids, Michigan. Jay is the owner and a great guy to work with and his experience in this area is unsurpassed. He has been building big block nitrous bikes and drag racing for many years and has been involved in countless Hayabusa nitrous projects. (www.stedmanracing.com or by phone at 616-261-2482) Sometimes it is those little things that make the difference in an easy job and a lot of hours sitting around scratching your head. As I said this was my first install of a nitrous kit so I had lots of questions. Jay was there to answer each and every one of them too. He even called me on a Saturday to answer a question I had left on his voice mail late Friday night. Now that is service!! You can also email Jay directly for technical questions at tech@stedmanracing.com.

The kit from Nitrous Express that I used (part number srp-6005) sells for $699.00 and has the stainless steel lines which I suggest as a safety measure to prevent virtually any chance of a rupture or problem with anything wearing through a rubber hose. I also like the 18" long braided lines as they give you more flexibility in mounting the electric solenoids. All of these features are standard on the NX kit but not on some other products so look carefully before you buy from another company. Once you get the kit I suggest you look over all the parts and familiarize yourself with the basics. Bottle, hoses (blue for nitrous red for fuel) solenoids which are also color coded, nozzles, wiring, relays, and the jets that go inside the nozzle and determine your horsepower by changing the amount of nitrous and gasoline that is sprayed into the cylinder. The kit comes with jets to obtain 40, 60 or even 100hp. That's right you can add up to 100hp with the proper setup. Though I don't suggest you try that without a few changes to the bike.

This article is not meant to replace the instructions that come with the kit so  I am not going into every single detail.  I am simply trying to hit the high points  and show how easy the system is to  install and ride. With that said, let's get  to the good stuff. The first and perhaps  most tedious job is locating the proper  location and drilling the intake runners for the nozzle installation. If you look  in the picture (right) you can see where  I have located mine. There is also a  similar photo on Stedman's web page  with a good look at the nozzle location. Click here to view it.

In order to drill the head while in the bike you have to take a few precautions to insure no metal shavings from the drilling gets into the combustion chamber. I very tightly packed each intake runner with several layers of paper towels before each hole was drilled and tapped. Then before removing each piece of paper I carefully vacuumed that runner with a powerful shop vac. I would then remove one piece of the towel, and vacuum again etc, etc. It is also helpful to rotate the crank so that the intake valves are completely closed in the cylinder you are drilling. This will allow you one last fail safe in the event a small sliver of metal gets by the towels and vacuuming. 

Once the head is drilled you thread the hole. Be careful not to tap it all the way and allow the nozzle to cut the last 1/8 of a turn. This will take a bit of trial and error but it is worth it in the long run to get a 100% air tight seal. Next thread the nozzle so that the entire mouth of the nozzle is inside the head and is pointing TOWARD the valves. This allows the nitrous/fuel spray a direct route into the combustion chamber when squeezing. I also added a bit of Permatex Quick set Auto Epoxy around each nozzle to ensure a good seal.

After the nozzles are in and the epoxy has set, you can install the jets of your choice and finish the solenoid installation and mount them. For this project I decided to use the 40 hp jets. This is by far the safest as it allows me to run with pump gas and I don't have to retard timing. Below is a chart with some general tips on fuel and timing retard for various combinations. If you decide to try the 60hp or higher jets, I suggest you talk to Jay directly for more information on fuel and timing retard. As you can see in the photos the nozzles fit in the intake runners nicely.

Another really cool part that comes with  the Nitrous Express kit is the throttle micro  switch. ( see photo right) This switch mounts to the cable side of the linkage  on the throttle bodies and prevents the  nitrous kit from spraying unless the  throttle is 100% open. This is a great safety  feature as the bike should not be sprayed  at less than 100% throttle or less than  about 6000 rpm's. This will ensure sufficient intake velocity to direct all of the spray  where it belongs, into the combustion chamber.

Next, I am going to talk about the two add on safety parts that I suggest you consider for your system just as I did mine. First is the fuel pressure safety switch. (part number srp-15750) This switch is an electro mechanical switch that wires into the electrical path between your push to spray button and the relay that fires the system. Don't worry too much now about the details of the wiring as they are provided in the kit. The purpose of this switch also known as a Hobbs switch is to sit in the fuel path between the Nitrous Express fuel pump and the solenoids and if a low fuel pressure condition is detected for any reason it shuts off power to the system thus stopping the nitrous spray. It basically prevents a nitrous lean condition caused by any fuel problem. As you may know this is not a pretty picture. Once installed you simply use a fuel pressure gauge and an ohm meter and adjust it to the desired cut off pressure. I set mine to 3.5lbs, which means if the fuel pressure falls below this level the nitrous system will shut down. It is a $48 option at Stedman and well worth it. See the photo below left.

The second safety device I used is the Stedman modified Dyna Shift Minder. Jay supplies a slick black box (above right) that uses the standard Dyna Shift Minder and converts it into an adjustable redline shutoff for the nitrous system. Once you determine the RPM that you want to cut off the spray, you simply use the dip switches on the shift minder to set the rpm level (adjustable in 125 rpm steps) and when you reach that point the box triggers the nitrous system (instead of the shift light in normal operation) and shuts down the spray. This is another safety device that is well worth the $120.95 extra cost. (part number srp-rss). He also has a very handy wiring harness that makes hooking up the entire kit a snap. It includes basically every wiring harness and hook up you need for the entire system. It even includes the Dyna shift minder wires to go into the 4 coil wires. I would not dream of doing one of these installs without this harness. (part number srp-nwh) Considering all the time and trips to the local parts store it saves, $62.95 is a bargain. 

Locating and mounting the parts on your bike is something that each of you will have to do depending on other mods that you have. For the nitrous fuel pump we highly suggest you mount it just behind the rear monoshock and just ahead of the rear swingarm brace. This keeps it away from prying eyes and away from the heat of the engine. A few zip ties and a piece of black duct tape around the pump should keep anyone from noticing it.

The bottle is perhaps the most difficult to hide if you are so inclined, but if you use the 2.0lb bottle it too can be hid. I have seen some people that cut the floor of the trunk and used some glass fabric and resin to make a nice little pouch to allow it to drop down low enough that the rear hump will easily slide right over the bottle. If you are running a long arm and hiding the bottle is not an issue then your job will be pretty easy as some arms come with built in bottle holders. 

As I mentioned before this article is not meant to be a replacement for the expert advice of Jay or Nitrous Express so I urge you to contact them with your specific questions. The kit will come with very detailed instructions to walk you through each step and I urge you to follow those directions carefully; especially the testing phase after you have everything installed and before you press the button on a live motor. Of course neither I, nor Stedman can make you a good mechanic or force you to follow the directions so you assume your own risks when you undertake this project. This is the way I did mine and it works great. How well does it work you ask? 

This system has been on my bike for about 6 months now and I have drained many 2lb bottles without so much as a hiccup. Below is a dyno chart of the bike before and after the nitrous and you can see it ROCKS. This is without a doubt the cheapest and easiest way to get a true 40-60hp out of your Busa and to easily dispatch your buddy's big block Busa or ZX12. Total parts cost including the extra safety items I included retails for $930. However if you order the entire kit together Jay is willing to make a deal for dragbike.com readers from now until August 15th for $799. The part number for the entire kit is srp-1300. Email them directly at sales@stedmanracing.com for more information

Compare that to a typical engine rebuild with cams, pistons head work etc and you will see that this is a far better deal and actually results in more HP. You can see this basically stock bike got about 203hp on the juice. The same bike before the gas ran a 157 hp. Not bad considering I used the smallest jets huh? This bike picked up an honest 46 hp. Another good thing about nitrous is that when you are just riding and around not on the bottle your bike runs stock, and is in no way different than a stock bike. But when you open that bottle and press the button it will be your opponent repeating that familiar phrase " Houston we have a problem". The problem will be that he just got smoked.

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