Synchron-Ease Installation Instructions
1. Remove fuel tank per factory shop manual instructions.
1B. (Figs.1&2) Remove 2 outer screws from #3 carb diaphragm cover.
1C. (Figs.1&2) Remove vacuum fitting caps (one per carb - only 2 shown).
2. Place rag below the carbs to catch dropped screws. You may be able to retrieve old
screws and springs with magnet, but new screws are 304 stainless and not magnetic!
2A. (Figs. 2&3) Remove the carburetor balance adjuster screws. They are mounted on the
rail that runs the length of and in front of the carb set; one between each pair of carbs.
Being careful not to lose the springs. Count the number of turns that it takes to fully remove
each screw and using supplied custom made ball end hex-tool, reinstall the new cap screws
with your springs an equal number of turns. This will give you an approximate setup.
4A. (Fig 4) Install Synchron-Ease bracket on outside of right hand carb with screws
removed in step 1B, or from new Synchron-Ease stainless steel screw kit.
5A. (Fig.5) Assemble brass fittings to Synchron-Ease bracket with barbed fitting
and washer on side with JBQ logo; compression fitting opposite. Using 7/16" &
9/16" wrenches, tighten the brass fittings on the bracket. For best appearance,
have the flat surfaces of each barbed fitting nut parallel with the others.
5B. (Figs. 5&6) Insert nylon hose into
compression fitting; longest on left,
shortest on right. Ensure that the
tubing goes into the collar inside the
fitting. Tightening the fitting without
the tubing completely inserted will
ruin the collar and the entire fitting
will need to be replaced.
As shown in Fig.6, remove the nut
from the compression fitting to
ensure the tubing goes into the
collar. Carefully tighten compression
fitting while holding tubing all the
way in, until the tubing is secure.
6. Although Fig. 7 shows entire kit, it illustrates the tubing setup: longest on left, shortest on
right. Starting with the longest one, cut nylon tubing to length about 1" (25MM) short of the
vacuum fitting on the intake side of the furthest carb. Using supplied rubber hose
connector, connect nylon tubing to the carb's vacuum nipple. Repeat for remaining carb(s).
7. Reinstall fuel tank, connect vacuum gauges or manometer to barbed fittings and balance
carbs per shop manual using supplied custom made ball end hex-tool to adjust the balance
screw(s). Very large hands may require the tank to be lifted (not removed) to work the
adjustment tool. A small block of wood (1.5" thick) should be adequate. It is also suggested
that since the engine should be at operating temperature, suitable work gloves should be
worn. A flashlight is also helpful to getting the tool into the adjustment screws.
8. After the carbs are properly synchronized, install the vacuum caps that were removed
from carbs in step 1C onto the barbed fittings.
9. GO RIDE!