1979 Suzuki turns but doesnt start?

Well, I don't think it's a spark plug problem. The 2 uncleaned plugs would have to be almost melted for them NOT to work. Plugs work no matter how dirty they are, they just don't work well. So I doubt it's the spark plugs being the problem.

Things you need for the engine to run:

a) gas

b) air

c) spark or electricity

Has the bike run before for you, and you cleaned 2 of 4 plugs and then it doesn't work? Or are you trying to start the bike when you've never run it before?

As I said, plugs have to be totally messed up to not work. So doubt that's the problem.

So either spark or gas. And that includes timing for the motor to supply the spark and gas at the correct times.

I now that Suzuki GS550, almost bought one. Go to walmart, buy couple cans of their cheap carb cleaner spray, and hose the carb down well inside and out. Might be some "varnish" inside that has hardened, which is a gas residue from old age. The carb cleaner will dissolve it and any dirt inside, too.

How old is the gasoline in the tank? If it's been sitting for years, you might need to drain tank and put in fresh gasoline.

Also consider that a car or truck's spark plug WIRES need to be changed moderately often, so that might help, because the electricity going thru the wires will wear it down easily.

I have had old cars, and was amazed at how easy the motor turned after installing new spark plug WIRES. So you might consider that too on the bike.

And what about a good air filter? I had old Honda that used a foam belt soaked in oil as filter. Check your bike's. I forget if bikes had fuel filters, but see about that, too.

That depends on the type