Here are a few of the tools you'll need. A hand-held mirror, some longish needle-nose pliers, a nice long #2 Phillips screwdriver, the factory carburetor idle mixture screwdriver, and an aerosol can of Berryman's Chemtool B12 carburetor cleaner. Aside from this, some assorted general hand tools (14mm wrench for example) may also be needed.

Remove the upper rear engine hangers to get better access to the carburetors and to allow room for some of the tops to come off. You don't need to remove the front engine hangers or lower the engine or any of that stuff.

It looks as if the number two (from the left) carb top will not come off, but it actually will, just barely. Make sure you hold your tongue right. :-)

Once you get the slides out, check them out for wear, damage, cocked needles, amd most importantly, varnish. If they have much more than this (note the jet needle), they may have to come off the bike to be cleaned correctly. This isn't too bad though. Click on the image to view a larger sample.

Remove the idle mixture ("pilot") screws, making sure you also retrieve the springs, washers and especially the tiny o-rings. The o-rings tend to jam into the casting and don't want to come out.

This cavity, the mixture screw cavity, must be bare. Take extra care to fish out the o-ring that tends to stick inside the casting. A bit of stiff wire works well to dig it out.

Hold the hand-held mirror like this and with a flashlight, peek up into the mixture screw cavity. It you can't see shiny metal at the end of the hole, the o-ring is still in there. Get it out. The carburetor will not work right with the o-ring stuck in there sideways or torn. Click on this image to view a larger sample.

Take the spray hose from the Berryman's and sand or grind a taper on one end. This is important. This method relies on the force of the aerosol to be really effective. So don't skip this step. Click on this image to view a larger one.

Here we see the hose jammed (wedged) into the idle air bleed jet. Get it in there tight, and spray a few shots. Unscrew and remove the float bowl drain screw to let the cleaner out.

Repeat at all the idle air bleed jets, remembering that on the number 1 carburetor, the air bleed opening is hidden under the air cut valve cover and diaphragm. The idle circuit is the most important one to clean, as it gives the most trouble after the bike has sat a while.

You should see cleaner come out of the idle mixture screw cavity each time the idle air bleed is blasted in each carburetor. Once you verify this, go back and blast the idle air bleeds in each carburetor again, only this time cover the idle mixture screw cavity with your finger and watch for discharge of cleaner from the idle port and transfer port inside the carburetor. Click on this image to enlarge it.

Once the idle circuit is happy, move on to the other circuits, blasting and watching for discharge inside the carburetor where that circuit sprays out normally (at the outlet orifices). Shown is the secondary (or just) main air bleed jet being shot. Cleaner should bubble out inside at the center of the casting.

Here the primary main (1979 only) is being shot. Watch for cleaner discharging at the primary main outlet inside the carburtor bore (venturi).

The correct, factory way to eliminate the stops of the idle mixture screws is with a soldering gun or mini-torch. Heat up the aluminum flag and simply pull it off. You don't have to heat them much, but the parts will be hot, so be careful!

Don't forget to clean out the glue from the mixture screw so that a screwdriver will fit into it properly. Click on the image to view a larger sample.

Now the mixture screw can be adjusted just like in the old days. Shown is the factory mixture screw adjustment screwdriver. An aftermarket type should work well also.

Before reinstalling the carb tops, gently clean their brass bores using a bit of brake cleaner or contact cleaner and a bottle brush (don't use carb cleaner as it will strip the lacquer off the polished top).

It is not unusual to find grayish-green deposits on the slide's chromed shafts. This comes from the crankcase breather system, which feeds crankcase fumes into the air intake. Periodically clean this off and you will be rewarded with excellent working carburetors. To minimize this deposit, regularly purge the drain hose at the bottom of the air box. To avoid it altogether, reroute the crankcase breather hose to an independent breather filter.

While putting the tops on, the long needle-nose pliers comes in handy. This is carburetor number 3, the one that has the most stuff around it. Click on the image to enlarge it.

Here we see the air cut valve before its cover goes back on. Note that the o-ring must be in place also. Hold it in place with a touch of grease. If you would like to eliminate the air cut valve system, merely replace the o-ring with a circular punched out piece of inner tube. Click on this image to enlarge it.

Unless you just like doing this frequently, consider some preventative maintenance. Believe it or not, just draining the float bowls each season does absolutely nothing. On the other hand, this product, Sta-Bil, when used according to directions, will preserve the fuel for up to two years. It may prevent the carbs from ever gumming up again. It works. Click on the image to enlarge it. Available at most auto parts stores, as well as Honda dealerships.