When you look at a Nomad you notice the two big, chrome air filters. Well, all is not as it seems. The right air cleaner is fake. Here's how it actually works. Air enters the back of the left air cleaner through a small opening, goes through the air filter, travels between the cylinders through a small tube into the fake right side air cleaner, past some emissions devices, and finally makes its way into the actual air intake. A fairly restrictive factory intake.
A popular performance upgrade is to modify the intake for better air flow. Different versions of this modification can be found at Gadget's Nomad Fixit Page under 'Caddman kit'. It is a plethora of Nomad knowledge. The several variations that can be done are:
- replace the fake right air cleaner with a real open element air filter and leave the factory left side air cleaner in place.
I'm going to replace the fake right side air cleaner with a K&N filter. I'll probably leave the left side like it is. I like the looks of the big, chrome air filter cover. Once you open up the right side the left side doesn't provide much air.
NOTE: The factory fuel injection system is open loop (no feedback) so increasing the air intake will make the mixture very lean as the computer doesn't compensate for mass air flow. You'll have to buy one of several fuel adding devices available. I bought a Techlusion TFI from Custom Dynamics (P/N FI-1025). While I'm in the area I'm going to remove the reed valves and the idle control solenoids.
I bought a K&N filter setup from Summit Racing (P/N KNN-60-1070). It is a 9x2" filter to match the factory backing plate.
This is under the right side "air filter" when you remove the cover. The two air injectors are seen. On a stock bike all the air comes from the left side air filter via the small tunnel.
Wiggle the air injectors from their mounts and unhook the wires.
Next we block the hose to the air injectors. This is traditionally called 'marbling' because a marble is stuck in the hose to block it. I don't have a marble, but I did happen to have a cap that fit nicely.
The hose is blocked. When I get my block off plates ('coasters') I'll remove this air hose and the reed valves.
Something needs to be done with the loose wires so they WILL NOT touch each other or short to ground. Doing so can/will damage the ECU (computer). Some people just tape them up. I cut mine off at the grommet (green arrow).
Cover the vacuum ports.
Update: When I installed the cruise control I removed the vacuum ports and capped them off on top of the throttle body. I removed the air injector brackets. I also disconnected the crankcase breather (it's at the very bottom of the backing plate under flat piece of plastic) and ran it under the motor.
The stock bolt is just barely long enough to fit and I'm afraid it might come loose. I went to Lowes and got an M8 x 1.25 x 2" bolt and a matching wingnut. I cut the bolt to ~ 1 5/8" and used it for a stud.
Install the air filter and enjoy the new air gulping motor. Don't forget to add a fuel compensating device. Click here for my TFI installation.
The new right side air filter adds a noticeable amount of throttle response, especially when you crank the throttle at highway speeds. It also adds noise...the ffft, ffft, ffft of inrushing air and the clicking of the valvetrain. To me it sounds like a bad exhaust leak. After our trip to Kentucky I decided to see if I could do something to lessen the noise as I found it annoying. I decided to strike a compromise and swap the K&N filter to the left side. It will eliminate the initial restrictive inlet of the left side filter but air must still go through the crossover tube.
The first thing to do is remove the inlet snorkel. It is rubber and pulls out.
I traced the opening onto ductwork metal for the inlet hole blocking plate. This thin metal is easy to work with.
I secured the plate with pop rivets...
...and used sensor safe RTV to seal the plate.
Here is the finished product.
Update December 2006 - I switched the filter back to the right side to show a fellow Nomad owner how noisy it was. I was surprised when it wasn't near as noisy as it used to be. I didn't know why. Later I read a couple threads on the Kawasaki Vulcan Delphi forum that said a lot of the offensive noise (the pfft, pfft sound) is caused by the crankcase breather being connected there. I had rerouted this hose back when I installed the cruise control. I'm going to leave the air filter on the right side and see how I like it now that it's quieter.
Update May 2007 - I replaced my Cadmann setup with a Dragtron air filter kit.