Power Issues

[Black Knight]

Gentlemen

Here is my issue ...This bike has to pass the state of AZ emission's before it can be tagged and below is what has been serviced or replaced

all 4 carb's rebuilt and synced
all 4 spark plug's been re-gapped
all 4 plug wires replaced
all 4 plugs are getting fire
air filter cleaned
all 4 air/fuel mixture screw's turned out 1-1/2 turn's ..

now my question is it'll idle fine after it warm's up but if i open the throttle to say 3,000 rpm's i can hear some popping and a slight mis on the right bank . If i try and ride it about 100 yard's it sound's like it starving for fuel . I can't afford to put it in the shop and i'm thinking about selling it because it's being pain the rear to get it right .

I'm running out of idea's

[Nessism]

For one thing the pilot screws are in too far. I'd try 2.5 turns out and then tune them after the bike is warm until you achieve the highest idle speed.

I'd also check the petcock function. Fuel should flow freely with the valve set to prime, but not flow when set to On or Res unless vacuum is pulling on the valve. With some vacuum pulling on the line when set to On and Res, fuel should flow.

[Black Knight]

air/fuel screws=pilot screws ?


I thought the prime side of the fuel valve was for getting it to start when the tank ran out of fuel ?

So in other word's the On part for the fuel should be placed in pri ?

[Nessism]

air/fuel screws=pilot screws ?


I thought the prime side of the fuel valve was for getting it to start when the tank ran out of fuel ?

So in other word's the On part for the fuel should be placed in pri ?

Yes, the screws are the same. 1.5 turns is in too far. Open them further and play with them from there to achieve the best running.

Did you play around with the petcock to test it? As I said, check to see if fuel flows when set to prime. No gas should come out when set to On or Res unless there is vacuum pulling at the port. Many times the petcock won't flow enough gas when in ON or Res, won't shut off when vacuum is removed, will send fuel back down the vacuum line and into the engine, etc. That's why testing is necessary.

[BassCliff]

Hi,

It sounds like you are making progress. Keep up the good work.

Are we talking about your '83 GS1100GLD? I would encourage you to put your bike year/model in your signature file so that we don't have to go through your old posts to find out.

In the interest of thoroughness, here are some pertinent links:

Where Do These Hoses Go?
This guide explains the operation of the Suzuki vacuum petcock and illustrates the various hoses around the fuel tank, carbs, and petcock.

http://cycleorings.com
Get a kit from our friend Rober Barr to replace all of the rubber O-rings in the entire carb rack. It's always best to reuse the stock metal parts rather than using the lower quality parts included in most carb rebuild kits. Rober Barr's O-ring kit and a float bowl gasket is usually all you need, and it's much cheaper than carb "rebuild" kits.

Carb Cleanup Series
This is the proper, tried and true way to disassemble and clean your carburetors. Completely disassembling and dipping each carb body, and all its associated small metal bits, in Berryman's (or other) carb dip (for up to 24 hours) will ensure that all of the small passages in these carbs are thoroughly opened. Then reassemble with the new O-ring kit.

Synchronize Carburetors (@ BikeCliff)
Synchronize Carburetors (@ bwringer)
A couple of carburetor vacuum synchronization guides.

Plug Chops-Highest RPM Methods
A guide to setting your idle mixture screws (pilot screws?) using the "highest idle" method. Mr. Nessism gives good advice - start at 2.5 turns out and adjust each cylinder from there.

Carb Specs: (Float Height/Jetting/Tuning)

Carb Notes: (Synchronizing/Troubleshooting/Theory)
A lot of general information regarding carb setup and adjustment. Did you properly set the float height? Improper float height can cause fuel starvation.

Air Intake Repair: (Airbox removal, intake boots and O-ring replacement)
Airbox Sealing
Replace intake boot o-rings

The machine must also have an air tight intake system. Air leaks in the airbox, carb boots (intake boots between carb and head), or airbox boots (between airbox and carbs) will allow too much air into the system causing a lean condition or fuel starvation.

Replacing Exhaust Connectors
Exhaust leaks can also cause too much airflow through the engine making it difficult to tune properly. Make sure the exhaust gaskets and connector gaskets are in good repair.

Valve Adjustments (8 Valve)
Proper valve clearances are critical for combustion aspiration and to keep from burning valves, an expensive repair. Tight valves cause symptoms such as difficult cold starting and long warm-up times.

All of this information was included in your "mega-welcome" you received in your original thread. You can also find it in the READ ME page on my little website. I realize that this is A LOT more information than you asked for, but all of the above must be in good working order to ensure proper operation. Taking any shortcuts will leave you frustrated. Once all of this is taken care of you will have a great running, reliable machine.

Old bikes can be a pain at first, especially if they have been neglected, abused, or have been sitting around in a barn for years. Keep us informed of your progress. Let us know how we can help.


Thank you for your indulgence,

BassCliff

[Black Knight]

wished there was a member from the the forum close by me that could come by and help set these carb's correctly .

btw i think i've got some light smoke on the left bank ..so i'm not sure what happened ? . after i adjusted the screw's 2.5 turns out

[1_v8_merc]

Popping can mean, excess air, or excess fuel......

I had a similar problem as you.
It turned out to be the Mixture Screw on Carb #4 was not set right.
The screw had crud between the threading, and I have to turn it Differently than the other 3....don't know why....but it worked!


How clean is the gas tank?
Not running on stale gas?


If you're getting a mis-fire, that can mean one of your Carbs is blocked or slightly gummed-up, somewhere.....
(since you said you already replaced the coil)

You sure you cleaned the carbs good enough?
I know whenever I do a quick-cleaning of my carbs, they only run right 50% of the time. And if I let it sit more than 2 weeks, I get that "put-put" sound coming from the right bank.


You are using the proper diameter fuel hose, correct?
Are you running any after-market fuel filters?

Are you sure the Carb boots are all super tight?