Gadget Note: The Progressive kit AFB-1 was discontinued some time ago. If some enterprising reader should create their own kit based on the description below, I'm sure they could sell a few of them.
Update: The Harley Davidson kit 54536-02A, REAR AIR SHOCK VALVE/AIR LINE ASSY, along with a couple of part number 54320-97, PUSH-IN FITTING, 5/32IN may fill the need.
This tip was one of the first posted on the Gadget site in early 2002. Since then hundreds, maybe thousands of Nomad owners have installed it with good results. Now the owners of the revised 1600 model are installing them and reporting one significant difference. It is almost mandatory the saddlebag on the side you install the fill valve on be removed to air up the shocks. If you have a 1600 Nomad you'll probably want to take a 10 mm socket with you on the road when first testing air pressures or add some quick releases to your bags.
This kit was originally marketed for the front air shocks on Yamaha's Venture but works perfectly to keep both shocks at exactly the same air pressure on the Nomad or Classic FI (with air shocks) too.
What You'll Need
1- Progressive Suspensions AFB1 Air Shock Balance Kit. Your local dealer should be able to find this part in the Progressive Catalog and probably the Tucker Rocky Catalog too. If not there are many online sources including Cruiser Customizing. (Note, the Progressive kit is no longer available.)
The kit consists of two aluminum "knobs" that screw onto your existing Schrader valves and a very small plastic hose connecting the knobs. One of them has it's own valve which is used to fill both shocks simultaneously from your hand pump. Cost is about $22.00 at any MC dealer and ten minutes of your time to install.
After several years the tiny plastic tubing may become brittle. You can order more from Progressive. It's part number sa-afb-40. Order by phoning Progressive Customer Service at 714-523-8700. Two feet of tubing will cost you about a dollar.
Installation is extremely simple, probably taking less time than you'll spend reading the following instructions.
The BIG and let me stress BIG BIG BIG thing is not to try and over tighten these new parts on your stock Schrader Valve stems. You CAN and WILL break the brass stems if you get carried away.
Now that I've scared you let me tell you this is sooo easy.
The kit comes with two aluminum "knobs" each has a threaded hole for screwing onto your Schrader valve. The rubber "O" rings are inserted in these holes. It's a little easier if you put a bit of lubricant on them (spit will do just fine) and press them in with a small screwdriver. Don't use a pocket knife or you'll cut the O ring.
Now, remove the valve portion of the air valve from your shocks. I've written half a dozen times to Progressive suggesting they put a tool in the kit to do this but do they listen to me??? You may have one laying around the garage. If not visit a bicycle shop or tire store in your area and ask for an air valve remover. They'll hand you a valve stem cap that has a slotted thing on top. Use that to unscrew the Schrader valve. If there's any pressure at all in your shocks you'll get a little oil out of the hole. Don't worry about it. With those inserts removed your ready to screw on the aluminum knobs. First spin on the thin nuts that came in the kit. Bottom them all the way.
This is optional. You can use a turn or two of plumbers tape to make sure there are no leaks but the O rings really do a pretty good job.
Now spin on the knobs as the instructions say "no more than two turns after the O ring contacts the valve". This is a sort of "fingertip" operation. You'll feel the love when the O ring hits. Then just give the knob one more turn (or so) to line up the little black tit pointing it upward at about the 10 o'clock position oriented toward the bike frame. Now you can snug up those big skinny nuts on the back of the "knob" so it doesn't turn by itself. A really slim wrench will be handy for this. When adding air you may notice a little bit of movement but the knob shouldn't try to unscrew itself. On my Nomad and a couple of others I've helped install these on those little black tits just barely missed the bikes hard parts as they turned but never hit anything. Other installers have reported contact requiring the little black things be removed before spinning the knob onto the valve. Your bike may vary.
Once both knobs are installed just slide the little white plastic "keeper" over one end of the plastic hose and press the hose onto the tit locking it in place with the keeper. (there should be a picture how this is done with the instructions) Thread the plastic hose to the other side of the bike in a way that it won't get squashed or cut by the seat and, allowing some extra hose, snip off the excess. Slide the keeper over the second end and press the hose onto the other knob. Now you're ready to add air!
You probably know this but I'll mention it anyway. Only use a hand pump, preferably one you can see the pressure building on or a very well regulated compressor. More than about 45 pounds will blow the seals in your shocks and it doesn't take long to build that much pressure. You may eventually notice oil in the tubing. This is normal and is just the result of the shocks equalizing air pressure.
Pump in some pressure and use a soap/water solution around all fittings to check for leaks. If there is a leak (not likely) you can still give the leaking knob another turn (after unlocking the lock nut) but use fingertips. I've had a couple of riders write saying they've twisted the valve stem right off the shock and both blamed themselves for getting overzealous with the tightening. Don't worry, dozens have written saying it was the most useful 10 minute mod they've ever done.