1980 GS550L not starting

[mcblah]

I just bought a 1980 GS550L that wasn't running when I got it. It needed a new petcock which I bought and installed. It started up and ran for about 20 minutes. I took it for a short ride and though it had some issues with the idle being high after it warmed up (which, after some research here, I have a pretty good idea why) it ran pretty well considering it looked like it hadn't ran in several months. Today I went out and added some carb cleaner to the gas and started it up to blow it out some more and no luck. It would turn over but not start. Here is a list of what I did.

Verified gas coming out of the petcock when vacuum was applied to the other outlet.

verified gas was getting in carbs by draining the bowls and then checking to see if they filled back up and they did.

checked the plugs where I saw they were dry.

sprayed some carb cleaner in the air intake and heard it start to fire in reaction.

so it would seem that gas isn't getting to the spark plugs which pretty much leaves the carbs though I don't understand since they seemed to work fine the day before when you think they would have been even more junked up.

Am I on the right track you think?
I have never worked on carbs before and it seems like it's pretty hard. Even just taking them off to inspect them could screw things up I would imagine. Is there anything I can do with them without taking them off?

Hopefully I was able to give enough info to make some sense of my issue. Any help would be appreciated.
This board has been a great help already.

[Billy Ricks]

You need to clean the carbs and check for intake leaks.

[marvinsc]

If it sat for any Length of Time which it sounds Like it HAS, You have Carb Issues. There is a Carb Cleaning Paper on this Site that You might Find Helpful.

[Planecrazy]

Billy (Ricks) is one of our carb gurus ... if he says you need to clean the carbs, guess what?

Good luck with it! Follow the carb clean tips on the site and you should do just fine, and welcome to the forum!

[mcblah]

Thanks for the replies, they confirmed my suspicions. I still have a couple of questions though.

Why did it start the 1st day when it had been months since it had ran yet not the second day? My thoughts are that stuff got stirred up when it was running for those 20 minutes and then settled back differently blocking something that it didnt the day before, does that make any sense?

Is there any sense to clean it without doing a complete rebuild of the carb? From what I have read on here it seems that there are a lot more things to readjust when you rebuild a carb than when you just clean it and if I can avoid some huge issues by just cleaning it then that seems like a good idea for me.

Thanks again for the info.

[mcblah]

update
I cleaned the carbs out really well, they were pretty gunked up and I thought for sure I would at least hear it try to start but it pretty much sounds the same. I may need to replace some of the intake boots as the two middle ones dont seem to be long enough to seal properly.
Would not getting a good seal prevent it from trying to fire? I would think it would make it run poorly but that it would try to fire.

Also I am confused about the part numbers for the replacement boots, the parts diagrams show two different part numbers for two of them and no part numbers for the other two. Are they all the same or is one different than the other three?

which position should they be in, wider part on top or bottom?

I am checking the electrical system using the guide here as a resource but so many of the tests involve having the engine running. What specific area of the ignition should I focus on that would prevent the engine from trying to fire?

thanks again for any help