Carb sync and 'buzz' Last night I did my first carb sync. As usual I took it nice and slow the first time. I used the Motion Pro Deluxe model that I got from JC Whitney. I wish I had bought the Carbtune II instead. I guess mine is OK but I think the Carbtune may be nicer because there is no assembly involved with it. I think that when you buy something that is called the 'Deluxe' model and pay around $50, you should not have to assemble it in the first place but if you do, there should be very good instructions included with lots of drawings to show how to do it. There weren't. The best part of doing a carb sync is warming the engine up. It took me about 2 hours worth of riding to get the engine sufficiently warmed up. :-) I had already bought the matching Motion Pro Aux Fuel Tank before I found out that there is more than enough fuel in the carbs to do the job without a fuel supply attached, even if you're slow and deliberate like me. Well, I hooked up the aux fuel tank and started to do the adjustment. After I had messed around with it for a good while, just for my own experience and experimentation, the bike died. I had forgotten to turn on the petcock on the aux fuel line! It had been running the whole time just on the fuel aready in the system. Getting set up to do the adjustment isn't hard. After the bike is warm, place the bike on the center stand. Remove the seat and the side panels under the seat. Unhook the fuel lines from the petcock. Disconnect the fuel gauge sender. Remove the gas tank. Unhook the hoses attached to the top nipplez (alternate spelling) on the carbs. Attach the hoses of the carb gauge to the carbs. Start the engine. Slight adjustment to the screws is all that is needed. While watching the mercury in the gauge, turn the screw between the first and second carbs. Turning in one direction raises the reading on one tube and lowers the reading on the other. Turning the screw the opposite direction has the opposite effect. Just set them where they are even. Do the first and second carbs first, then do the third and fourth. Then do the center screw which will match the left pair to the right pair. My carbs didn't need the center screw adjusted. Thank goodness! You need a long skinny screwdriver to get to it. None of mine would reach. You can use either a slotted tip or a Phillips screwdriver to make these adjustments. They both have thier good and bad points. The slotted tip driver must have a thin blade. You can make adjustments with it without putting downward pressure on the screws. Pressure on these screws increases the rpm's and can give you false readings if you are not carefull. Slotted screwdrivers however, are harder to keep in place while looking at the gauge and making adjustments. Phillips drivers (a #2) stay in place but require pressure. Take your pick. My usual rpm range while riding is between 3K and 5K rpm's. I had a really bad buzz just below 4K rpm's before I did this adjustment. It had been there since new. The bike is a '00 model with almost 10K mi. This is it's first sync. Several others on this list also have stated a similar problem. I decided to do what I could to correct this by syncronizing my carbs while the engine was turning 4K rpm's. You have to be careful while doing this because you could suck the mercury into the engine. Once I got the carbs synced at 4K rpm's, I released the throttle back to idle and the mercury levels were way off. They had been as close to perfect as I think could be done while at 4K. It is supposed to be acceptable for the carbs to be within 2 cm Hg. Well, even at idle, the carbs were within this spec, but just barely. I figured that smooth and even carburation at speed was more important than a smooth idle. So this is a bit of a trade off. My idle speed never was smooth as silk. Now it is just a little more lumpy. Just a very little bit, though. The big news is performance while riding. It now runs quieter, smoother, more of a high-performance rev than a raspy, noisey, metalic sounding rev. In sixth gear at 70 mph, the engine now turns about 400 rpm's less than before (if memory serves). Power is smooth and linear. It just feels and sounds RIGHT! Remember that buzz just under 4K rpm's? I don't!! It is all but eliminated! I will trade a slightly rougher idle for highway smoothness any day! I am interested in finding out if this will improve my gas mileage. I'll let you know. I am currently getting 39mpg. In closing, I must thank the members COG and this list, and especially the MorrowMarsh Tech Index, where there is a very good write up on this subject with pictures. Thank you everyone! To those who have not done this, YOU CAN! I will help any way I can, just ask. And I know you can always count on the list, too! Good riding and wrenching to you! Jonathan