Looking to get my carbs synch'd

[Robotic]

Anybody in south florida know of a good shop or trusted person? My local shop wants a lot of money. He said 8 hours worth.. I can't aford to do that if it's not really broken. I cleaned the carbs about a month ago and just added a custom shorty pipe. I just want bike ticking the way it should be.

[Wild-Bill]

Do a search on here for sync gauge. You can build your own gauge and do it yourself for about $10. It's not a hard job. You just have to warm up the bike (10 minutes of riding), pull the tank and fairing to get at the carbs, turn up the idle to 1800, hook up the gauge, adjust some screws and turn the idle back down. Nothing cosmic.

[Robotic]

sounds easy enough. I'll look into it. thank you

[hardlydangerous]

Bench Sync them, trust me its good enough. Just align all the butterfly valves the exact same and your golden. I always set up every carb this way before I install them after cleaning and they are always within 1.5 cm on the Motion pro sync tool.

8 Hours? holy %$#@ what the hell are they doing that takes 8 hours? I can remove, seperate, clean them in the aultra sonic cleaner, re assemble, bench sync and put the bike together in 4 to 6 hours. To just sync the carbs it take 30 minutes tops

[scottynoface]

Seriously, 8 hrs? Almost 500 bucks to synch carbs? What a joke...

[Robotic]

yeah, it didn't take me that long to clean them and that was my first time. are you talking about running the bike. upping the idle. take off the airbox and just looking to see if they look close?

[Wild-Bill]

Bench syncing is where you pull the carbs (you usually do it after rebuilding the carbs, before installing them) and look in the engine side of the throat. The butterflies should all be at exactly the same position. Best way to check this is with the old Mark I eyeball. Adjust the idle screw until #3's butterfly covers exactly half of that little bitty hole at the bottom of the throat. then adjust #4, #2 and #1 so their butterflies are the same as #3. Back off the idle screw so it's just barely touching the bellcrank and re-install the carbs. If you don't trust your eyesight you can do the same thing using a piece of safety wire (or any other piece of round wire) as a feeler gauge to get them all the same. Just set #3 first using the idle screw and go from there.

I've had mixed results with bench syncing. The last bike I did, the bench sync was so close that we didn't have to do any adjustment at all based on the vacuum levels. Spot-on! Other times I've had to do quite a bit of adjustment to get the vacuum right but then, I'm a perfectionist when it comes to tuning. The bench sync gets you in the ballpark. The vacuum sync accounts for any differences in the valve settings, cylinder wear, intake oddities, etc. In theory, it shouldn't be needed. In reality, the valve settings are never exactly the same. If you don't vacuum sync you may be a bit off which will result in excess vibration, idle roughness and lower power. If you don't have any of that then (for the price a shop charges) I'd leave it alone until you happen across someone with a gauge or buy/build one for yourself.

[edrawba]

http://www.vfrdiscussion.com/forum/index.php/topic/16200-homemade-manometer/

[DClark]

I bit the bullet years ago and bought a Morgan tuner, never regreted it. Don't know about the smaller bikes, but my kat 1100 tends to get real buzzy. Maybe it is just my age as the arithitis in my hands really notices the buzz.
I have found that a carb synch does wonders as even the slightest out of adjust on my bike creates buzz. I think it is just the nature of the beast. Even after a synch, I still ride with gel grips, grip wraps, finger less gloves with gel inserts and full gloves with gel.
Oh, and if you don't when the bike last had a valve check, do that before a synch.
Happiness is a bike with valves in close spec, and a razor accurate synch.

[Wild-Bill]

+1000!