You might have spent some time tuning your bike, even had your carbs off for cleaning, but your engine still does not run smooth. The answer is:
Synchronice your carburettors!
Before you start this procedure, you must have done all the other tuning work first. This is the LAST thing you do, after all this is done:
1. Clean your carbs and replace parts if necessary.
2. Adjust the air screws
3. Assure that your fuel tank, petcock and fuel hoses are in order.
4. Check your spark plugs, clean and adjust electrode opening, or get new ones and adjust them.
5. Manually adjust your ignition timing. If your bike is idling well, you can use instruments like
stroboscope.
6. Adjust valve setting.
All this done, your next step is to synchronize the carbs. You need a tool for this, either vaccum gauches, Morgan carb tune tool, or a homemade set.
This is the procedure:
1. From your manual, Clymers or other information base, learn what your measuring is
supposed to be.
2. Take a 5-10 minutes ride if your engine works, let it get warm. Let it idle nice 1000-1200 rpm.
Stop engine.
3. If it does not run, just follow the instructions below.
4. Open the petcock valve and let the fuel fill up the carb bowls.
5. Remove the fuel lines from the petcock, open the seat and remove the tank.
6. Remove the screws on the inlet manifold and replace them with the screws to your carb
synch tool.
7. Connect the hoses from the synch tool to the screws on the inlet manifold.
8. Start the engine and remark the cylinder with the closest reading to optimal. Stop engine.
Do not touch the adjuster screw on this carb, but loosen up the locknuts on the 3 other carb
synch screws. See picture below.
9. Start your engine, and read the measuring. Adjust the 3 carbs to get as close as possible to
the one you did not touch.
If your engine does not start, screw all of your synch screws clockwise (down),
and then counter-clockwise one turn. Try to start. If not repeat procedure with another turn.
Eventually, it should start.
10. Adjust the carb that is way out, and see what happens on the gauges. You will soon learn,
that adjusting one, the other carbs will also be affected. Funny, but makes it a bit hard.
Be efficient, you will soon run out of gas. I sometimes stop the engine, when I adjust the
carbs, only to save fuel so I dont have to connect up the tank again.
Or make an auxilliary tank!
11. When you get closer, use your ears, you will hear when the engine smooths out!
12. The reading does not need to be exactly the same on each carb, but pretty close.
Listen to the engine! Rev the engine to see if it settles down nicely on the same reading.
13. CAREFULLY tighten the locknuts, keeping your screwdriver on top of the screw so it does
not move, and do not press it down. This procedure will most likely tease you a little, unless
you have the Honda wrench tool set for the job.
14. Coffe time
15. Test ride time