cb750 won’t start. Please help

[frost]

I just purchased an 81 cb750 for my first bike and I am completely new to everything. It doesn’t idle well, and you have to keep reving it to keep the engine going. The last time I got it running I had to put into gear right away and get moving as soon it started up or else it would cut out. Later that day I tried to start it up and I couldn’t get it to turn over, even with the choke out and reving it and whatnot. Now the battery is dead, so I tried push starting it and it got close to starting up, but wouldn’t turn over.

From what I have researched the idle problem has to do with the carbs, but other than that I have no idea what to do.  

Any help is much appreciated!

(Also as a side note it’s fairly cold out, 30-40 F, so I don’t know if that has something to do with it)

[TOOLS1]

Hi Frost
The first thing to do is download the factory service manual from the manuals thread here. As for the idle, it sounds like your pilot jets are plugged. However there might be more then just the pilot jets being plugged up here. You will need to do a through carb cleaning. There is a good write-up on cleaning the CV carbs your bike has in the CB750 section here. It is very detailed with good pictures. When you do have the bike running correctly, you will want to check the charging system. You want it to have @13.4 volts with the engine running at 2500-3000 RPM.
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[frost]

Ok, so I'm in the middle of taking the carburetor apart to clean it, and while I was taking the slide covers off I flipped it over and saw this piece underneath where the #1 carb was. I have no idea what it is or where it came from. Any ideas?  

[TOOLS1]

It is the jet nozzle for the needle jet. If you look down into the carb where the slide goes you will see where it goes. Some go in from the top, and some the bottom where the main jet is, I am not sure about the CV carbs at the moment, it has been a long time since I worked on them.
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[shinyribs]

My memory may be bad, but I've been inside way too many CV carbs and that piece doesn't look familiar at all. Any threads or anything on it?

[frost]

I figured out what it was (after I saw another one fall out lol), and I cleaned out the jets. One of the screws on the slide cover for carb #2 is stripped, so I couldn't do a complete cleaning, but I cleaned everything else I could. I reinstalled it, but its still not turning over. Its just doing the same thing.

Could it be the spark plugs? I may just have to take it into a shop because I'm way out of my league with all this.

[TOOLS1]

"turning over" is a term that could mean several things. I am assuming you are saying that the engine will not start, but it is cranking. Take a spark plug out, put the lead on it, ground it to the engine, and hit the starter button. Look for spark at the tip of the plug.  If it has spark, back to the carbs, if it does not have spark, look at the ignition.
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