Installation – Right Side
Once you have everything ready, you need to remove the air cleaner covers off both sides of your bike. They are held on by an allen bolt. I didn’t pay attention to which size it was, I just have a ton of them lying around so I found one that fits and removed the bolts. You won’t reuse the bolts, but you’ll want to save the washers.
Here is the right side of the bike with the cover off.
Next, you’ll need to pull both ICS (Idle Control Solenoids) off their tabs. They are not held on by anything other than friction from those rubber ‘ears’ (indicated by the YELLOW
arrows) that surround them. Just pull both sides of each one and they’ll come off.
After you have both solenoids off, you’ll need to bend each of the 4 metal tabs inward about 1/8th of an inch. The only reason you bend them is to give your new air filter a little more room on the outer edge. The tabs are made of a soft metal and bend easily with just hand pressure. You do not need to bend them much as you still want to remount the ICSs later. (You have the option to not reinstall the ICSs, but more on that later.)
Next, pull both of the ICSs off their tabs, and you’ll see the rubber hose that goes to the Reed Valves behind the front ICS. This rubber hose is indicated by a RED
arrow, and is where you will shove your marble if you intend on blocking the reed valves. Some of you may have already disabled your reed valves, so this hose would be missing if they were removed, but for an installation like mine that needs to be easily revertible to stock, I am leaving this in place.
If you are planning on doing the resistor mod, don’t plug the hose with the marble yet, as you will need to remove this hose pretty soon.
Optional – Doing the Resistor Mod
Once again, you do not need to do the resistor mod if you already have an aftermarket tuner like a Power Programmer, FI2000, or some other mod on your bike. You also do not need to do the resistor mod if you have a carbed bike. This only applies to fuel injected bikes. If you do not have these, you will definitely want to add the resistor as doing an air mod like the Caddman mod can make your bike run dangerously lean. If you are skipping the resistor mod step, jump to Step 12.
The resistor needs to go inline with the air temp sensor, which is behind the right side filter backing plate. In the following picture, the tip of the air temp sensor is indicated by the YELLOW
To remove this backing plate you will need to remove the four allen bolts surrounding the throttle body opening as indicated by the RED
arrows. You will also need to remove the GREEN
hex bolt, and both BLUE
Philips head screws.
Once all 4 allen screws, the hex bolt, and the two screws are removed, you’ll also need to remove the PURPLE
hose clamps on both of the hoses right under the throttle body. You just need a pair of regular pliers to squeeze the tabs on the hose clamps and pull them down the hose and you can then slip the hoses off their connectors which go behind the backing plate.
You’ll also need to pull the BLUE
reed valve hose through the backing plate. In this picture the front ICS is blocking it, but it’s behind it. You can see a better picture of this hose in the picture in Step 4.
Lastly, you’ll need to pull the YELLOW
drainage hose out. There is nothing but friction holding this on, so work your hand back there and yank it out from behind.
I drew a RED
arrow to the wiring harness that goes through a grommet to the back of the backing plate. You will not be able to easily remove these wires, so just leave them be. You’ll be able to completely turn around the backing plate so you can see the back of it without these wires getting in the way.
Now that everything is disconnected and out of the way, you’ll be able to completely turn around the right side backing plate so you have access to the air temp sensor’s wiring. The harness is indicated by a PURPLE
Strip away some of the stock electrical tape going around the wires. There are two wires going into the air temp sensor. One is pink and one is brown. The one you’ll want to work with is the pink one.
Now the next step involves soldering a resistor inline with this pink wire. Choosing what resistor is right for you is up to you. I recommend reading the following article at Gadget’s site:
This article talks about why the resistor mod is done, and how the Vulcan’s ECM (Engine Control Module) interprets what it receives from the air temp sensor. Essentially, as the outside air temp is colder, the air is denser, so the ECM reacts to that by adding more fuel. If you trick the ECM into thinking the outside air is colder than it actually is, the ECM will respond by sending more fuel into the engine. Normally this could cause any engine to run rich (too much fuel, not enough air), but since our engines run close to lean from the factory, and we are adding an air mod which is putting MORE air into the engine, we want more fuel to balance things out again.
There is no correct resistor value for what is “right” because the “right” resistance varies upon the actual outside temperature. It is commonly believed that any value between 500 and 1k ohms will work. The best thing to do would be to install a potentiometer (variable resistor) which has a dial that allows you to vary the resistance to find the correct resistance. I was unable to find a suitable potentiometer at my local Radio Shack, so I took a stab in the dark and went with a 680 ohm resistor. If I determine that my bike is still running lean after the install, I can swap that for a higher resistance resistor, or I can go with a lower resistance one if I find myself running too rich. Like I said before, the actual value you use is up to you, but it’s probably better to err on the small side rather than put in one too big and cause your bike to dump too much fuel into the engine.
Now that we got that out of the way, get out your wire cutters and make a snip in the pink wire. Don’t cut it too close to the plug or else you won’t have enough wire to solder on. Once you have your cut made, strip about ¼” of insulation off both ends of the wire, and solder your resistor in place. Resistors are NOT polarity specific, so it does not matter which way you put it. Another word of caution is although resistors don’t easily get damaged from heat, don’t keep your soldering gun on the wires for too long as too much heat for too long will damage the resistor.
Once the solder resin has cooled, give it a couple tugs to make sure your soldering is good and that it will not come apart. The next picture is a bit blurry because I couldn’t get my digital camera to focus properly, but this is what your resistor (PINK
arrow) should look like when you’re done.