carbs wont stay synced

[Brian S]

Hi guys. I rebuilt my carbs using kits from Randy at RPM, great kits. The bike runs really nice but the carbs go out of sync and the vibes come back a couple times a week. I'm guessing my sync screws are vibrating? Just wondering if anyone knows of a fix for this, heavier springs on the screw? I wouldn't want to use loctite but is there something else I can put on the screws to keep them in sync? Not sure what to do here and greatly appreciate some advice.

[yamaha fj rider]

Brian the adjustment screws should not loosen up try putting a washer or two under the spring increasing the tension. Was the bike up to operating when you synced the carbs? Hope this helps? 

Kurt

[Brian S]

It was up to temp and ran great for most of the day. It runs smooth for a little while and then the fairing starts to buzz again.

[SlowOldGuy]

Go in and cushion the fairing mounting points and joints.  You won't stop all the vibration on this engine.

DavidR.

[yamaha fj rider]

Brian is it just one screw or several? Try the washers see if that helps. First time for everything best I can think of at the moment. Maybe try marking them to see witch ones are the problem. Hope this helps.

Kurt

[Brian S]

WOW! I was way off. Blame it on being a noob but I went though old posts on vibration and kept seeing Arnie mention broken frame bolts and didn't give it a second thought because I looked the bike over and didn't see any. Besides that the problem would come and go. Well the frame bolt thing got me thinking and I started checking how tight the lower frame rails and motor mounts were and found some just snug. Broke out the torque wrench and went over the bike and it's like a new machine. guess it goes to show being thorough on a used bike can save alot of hassle. On the plus side all that maintenance has is running sweet.