I have a 1982 suzuki 550gs ran fine let it sit 2 days and wouldn't start again. It has spark and compresion and fires just won't run had a friend tinker with it and got it to run but was only running on 2 instead of all 4 cylinders can anyone help figure out what the problem is

SOURCE: ive just bought a suzuki gsx750f 1989 model it was

Backfiring is typical for 'lean' conditions and stuck inlet valves.
check also the spark plug condition, replace them if any doubt on their age exists.
Check compression to discover open valves.
Clean out the carburettors.

SOURCE: Cant get it running right

Invest in a FACTORY service manual. By the end of the first hour the manual has paid for itself. Don't get a Haynes or Clymer manual. Set the valve clearances and cam chain tensioner. Install new stock NGK spark plugs. Clean or replace the air filter.

I don't have a manual so I will assume the bike has carbs and not fuel injection.
Remove the water trap bowl at the bottom of the petcock, (gas valve). Is there any water or trash in the bowl? Drain a cup of gas from the tank. Is there any water or trash in the cup? Dump it, clean it and re-mount it, ( not all bikes have a water trap bowl ).

FOR EACH carb >
Drain the carburetor. There should be a screw on the lower side of the carb float bowl. Remove the screw then replace it after the fuel drains. After all carbs have been done, turn the gas back on and wait a minute for the carb to fill with gas. If the bike doesn't start and run properly then shut off the gas and remove the carburetors from the engine.

Remove the float bowl and clean the entire carb with a spray carb cleaner from the auto parts store. Wear protective goggles to avoid getting spray in your eyes. Spray into all the little airways and fittings in the carb. Remove the idle screw and the air screw on the outside throat of the carb and spray into the screw holes as well.
< < READ CLOSELY > >
Be sure to put these two screws back in the same hole they came out of. IMPORTANT > do not tighten these two adjusters down. Only screw these in until they LIGHTLY seat. Now turn each adjuster one and one half turns outward. Put the rest of the carb back together and install the carb.

Also, sync the carbs such that the slides on all carbs begin to move at the same exact instant when the throttle is slowly turned. Let the float bowl fill then start the engine. This process should get you back on the road.

Please rate this solution. Thanks! Bebe!

SOURCE: 1986 Suzuki GS 450 won't start

Take the carburetors apart and either rebuild them or clean them thoroughly.

SOURCE: one cylinder does not fire.

check for comp on cyllinder next check fuel supply

SOURCE: 82 Suzuki GS650 Engine turns over but gets no fire to start.

take the plugs out and see if you have a spark get back to me