As promised, here is my Caddman Air Mod tutorial. I take no credit for thinking this up, nor do I take credit in figuring it out myself. The original instructions can be found at Gadget’s page here:
If you want to get straight to the install, skip the next section, as I am going to ramble on a bit with my intro.
Introduction / Theory
Before continuing, I would like to explain what my plans are and why I am doing this, as this mod may not be for everyone. What this mod will allow you to do is install a 9” round air cleaner that can be bought at many auto parts stores on both sides of your bike. Having these air cleaners on your bike is an alternative to the many aftermarket cold air kits available for the Vulcan motorcycle. While there is nothing wrong with any of those aftermarket kits, there were a couple things I didn’t like about them.
1. They aren’t symmetrical. When you install a Tornado or Hypercharger kit, it only mounts on one side of your bike. That leaves a big bare spot on the left side of the bike. Some people fill up this area with other things, but nothing quite looks as good to me as symmetry.
2. All of the aftermarket air systems protrude out more than the stock air cleaner and can get in the way of your knee. Some are worse than others, but I prefer something slim and not obtrusive.
3. Lastly, all of the aftermarket systems are quite expensive for what is essentially just an air filter and some tubing. This mod can be installed for less than $50.
My bike currently has a Vance & Hines Big Shot exhaust installed. It is a well known fact that in order to get full advantage of an aftermarket exhaust on Vulcan cruisers, you need to compliment it with a high flow air kit, and once you do that, you need some sort of electronic modification to your bike’s computer to adjust the fuel curves as the bike already runs dangerously close to lean from the factory. Many people complain about pinging on their stock Vulcans, and although the stock pinging isn’t anything dangerous, once you start pumping in more air into your engine, you could push it over the edge, so you do not want to do an air modification like this without somehow changing your fuel mixtures on the bike.
There are several choices for products that can change your fuel curves on your bike, but like the aftermarket air systems, they can get a bit pricey. Gadget’s site also mentions adding a resistor inline with the air temp sensor that allows you to ‘trick’ the computer into richening up the fuel mixture. Although this is a very primitive and non-exact method, it is essentially the same thing as what those aftermarket products do.
The resistor mod only applies to fuel injected bikes. If you have a carbed bike, you will need to manually adjust your carberators using new jets.
Although this modification is almost free (the only part you need to buy is a resistor), it does involve going a little deeper into the electronics of your bike and soldering a resistor into the stock wiring. Some people may find this scary, but I wanted to try it, so for this walkthrough, I am soldering in a 680 ohm resistor into the wiring harness coming out of the air temp sensor. If you already have a Power Programmer or a comparable product on your bike, you can skip this whole step, but since one of the points of the Caddman mod is to save money, you can try this to nearly accomplish the same thing.
I also am choosing not to completely remove my reed valves as my bike is still under warranty, and I want all these mods to be quickly removable, so I want to leave my bike as close to stock as possible. You can accomplish turning off the reed valves by shoving a marble up into the reed valve hose. I plan on doing this and will show this step during my walkthrough as well.
So anyway, onto the instructions.
(2) Spectre 9” x 2” round air cleaners and filter. The part number for what you need is 4770. The replacement filter is PN #4805. When you buy the first air cleaner, it comes with a filter, so you wont need to buy a new one until its time to replace it. There are other brand filters you can use in place of the Spectre paper filter. Its up to you to find another filter to use if you want. As long as its 9” round, it should work. I was able to find these filters at Auto Zone and they were $19.95 each. You will only use the filter and filter lid in this kit. The backing plate that comes in the packaging can be discarded.
(2) 8mm x 1.25 pitch studs approximately 35-38mm long. I was able to find these at a local Ace Hardware store. They’re not a national chain like Home Depot or Lowes, so if I was able to find them there, you should have no problem at a national chain. If you cannot find a stud in that size, any long 8mm x 1.25 pitch bolt will work as long as you cut the head off and make it approx 35-38mm long. The length isn’t crucial, but if you make it too short, it wont reach through the filter lid, and if its too long, it will bottom out on your filter nut.
(2) 8mm x 1.25 pitch acorn nut. You don’t have to use an acorn nut. A wing nut or a regular nut will work well. There are also nice air filter nuts that you can use, as long as theyre the right size and pitch. It doesn’t matter what you use as long as it fits.
(1) 1/8” sheet metal screw. This screw will be used to plug a hole, so its size isn’t too important. If you have a jar of screws lying around, I’m sure one will work fine.
(1) Toy Marble. You can even use the decorative kind you often find in the bottom of flower vases. Optional
A tube of silicone sealant. Optional.
Some scrap metal or tin and something to cut it with to make a block off plate from. Optional.
500-1k Ohm 1/4watt resistor. Optional.