Carb Synchronization

By Tony Anzalone

2002V-Star 1100 Custom

The carb sync is simple, but you need a "Mercury Stick" or factory matched "Vacum Gages" to do it right. The cost is the $20 to $40 range from JC Whiney or a cycle shop.

I have heard of some others newer more expensive tools and even a home-made version of the merc sticks but I have no experience with them.

I have already disconnected the AIS system which uses the rear cylinder vacuum port. The line is capped and still runs thru the tool box to the lower AIS pump area.

**Tech Tip: So to make my future life easier I ran another line from the front cylinder vacuum port to the same location and capped it also.  Now I can use both the front and rear lines to do the carb synchronization, with the Fuel Tank in place. Just open my tool box  uncap the lines and hook up the lines to the synchronizer.

1st warm the engine to full operating temperature.

Make sure your PMS idle mixture scews are set correctly. If you have a 90 degree screwdriver or carb adjusting  tool you can adjust at idle. Turn in till it slows down then turn back out till it reaches maximum increase in RPM or hight on your mercury stick.

Hook up the  mercury stick or gagues and raise the idle speed to about 1,200 - 1,500 rpm's.

There is a 7mm. nut that hangs below the throttle linkage, (carb synchronizer adjusting nut). The nut faces the front cylinder and can be accessed on the left side of the engine.

Turn the nut in either direction till the cylinders are matched on the mercury or vacume gages, as close as you can get them. The engine RPM's will slow dow a bit as you adjust. Bring  the rpm's up slowly to about 3,000 rpm's, then let it settle. If it is still out a bit  raise the RPM's to 1,200 - 1,500 and re adjust & re-check the sync till it is as close as you can get it..

Adjust the idle to the required factory range of 950 - 1,050 rpm's, cap the vacume lines and that's it!

**Tech Tip: To keep the fluctuations down on the mercury stick or vacume gages and make it easier to read:   I inserted my old 17.5 pilot jets into the hoses to restrict the flow and it works great.  Or you can just squeeze the flow down by useing a strong allagator clip to particially pinch the vacume hose.

Have Fun & Ride Safe

Tony Anzalone

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