Topic: First time synchimg carbs

[cbfivefitty]

Hey folks, I'm trying to synch my carbs on a 76 cb550f and I have a couple of questions about some problems I'm having.

1 after I start the bike I have it idling at 1200, I start changing the slide adjustments and the idle goes higher and changes the readings on the gauges. Now do I adjust the idle screw to bring it back to 1200? Or do I keep adjusting the slides to match the new vacuum readings?

2 is there a certain order or procedure of adjusting, like which cylinders to start with?

[strynboen]

number 2 kaburettor are the master ..it can not be adjusted...so get the others to fit that one..have you got that speciel tool to adjust the ´slides?? its easyer vith that..its one grib key to both adjust, and then lock the schrev
i use a extern airblower to kool the engine..if yoy can adjust it in few minuts ..its fine vitaut...but takes it longer ekstra kooling are needet..and a ekstern fuel tank..evt from a lavn mover..to feed the kaburettors

[Deltarider]

number 2 kaburettor are the master ..it can not be adjusted

His is a CB550F 1976, so all carbs can be adjusted.

[strynboen]

leave one as a marster..then there are only 3 do deal vith ..(.but start at low rpm. on the marster carb.it can easy reise by) getting all kaburettors in deal..

[cadman]

The principle is to get all 4 the same regardless of rpm.  You are simply raising or lowering the carb slides one at a time.  Raising one slide will of course raise the idle.  If you set them at a high rpm make sure you can back them off with the idle screw. Note air mixture screws will also effect this.

[tyler]

Make sure you mechanically sync the carbs by measuring and adjusting the slides first. Ensure the slides all move simultaneously when you move the main throttle and there is no loose in the linkages. Once that is done then you can sync them on the bike using vacuum gauges. Manual says to sync at 1200 but some bikes run better when synced at slightly higher rpm. I followed my manual to the tee and rebuilt my 350 four carbs and it they run great.

[Bodi]

If you had the whole rack apart you have to set a rough sync with the 4 adjusters positioned where the idle screw and choke throttle cam (if fitted) are usable. Then lock one adjuster down and leave it alone, pick whichever is hardest to get to. Then you adjust the other three to balance the vacuum across the 4 crabs - reset the idle to around 1200 as it changes when you move adjusters. There's no specific reading you need to get, just get all four pretty much equal. Blip the throttle occasionally to make sure everything is seating properly. If you have fluid filled vacuum indicators, be careful with this blipping so you don't suck the fluid out. Have a good powerful fan blowing at the front of the engine. Don't kill yourself with CO while doing it.

[cbfivefitty]

Thanks for everything guys, got them done just in time for a snow storm. Bike is running great now. It's amazing the difference.  I set carb 2 first locked it down and just did one at a time locking each one and matched to the new reading at higher revs. Lowered the idle screw back to 1200 and runs like a champ now.
Now with the air mixture screw, what am I looking for when adjusting that? right now it's one and a half turns off seated and seems fine but this is my first bike so I'm not really sure what a really well running bike sounds like.

[flybox1]

Now with the air mixture screw, what am I looking for when adjusting that? right now it's one and a half turns off seated and seems fine but this is my first bike so I'm not really sure what a really well running bike sounds like.

Do you have the stock intake and exhaust setup for your 550?
Honda already did the work for you for their stock setup and published this setting. Set it per the manual and forget it 

Mixture screw settings control just that. . . air/fuel mixture at idle.  Unless you have something that can analyze your idle exhaust gas, you have to rely on other methods.   If you have an exhaust or intake different than stock, your first place to look for what you setting 'should be' is your plug insulator color after a 3-5 minute idle on a set of new plugs.  Plug insulator deposits will show you how you need to adjust this screw.  Leaner or Richer.

[cbfivefitty]

Yea my bike only came with two pod filters and nothing resembling an air box so I got the special k&n filters that fit in the 550 frame seems like the original exhaust with a bit of rust. I guess I'm gonna have to tweak it a tad, oh well another excuse to learn more.

[Duanob]

As Flybox said use the spark plug color as your guide. Remove and number each one with it's cylinder so you know which carb to tweak if necessary. Post a picture back to see what they look like. My guess is all things being equal they should be on the lean side with the POD filter. But with a 40 your old bike you never know until you pull the plugs.

[tyler]

Oil leak