Help tuning the carbs

The thing about Craigslist is that you cannot, ever, rely on what the seller has told you except to surmise that it is even worse by a far margin.

I think this will be a fun and rewarding endeavor for you. I have the feeling that you'll get this all solved at some point and learn much in the process

I say that because i sure am learning

Take the points cover off and inspect the spark advance that it moves freely and is lubricated. THAT CAN ALSO CAUSE HANGING IDLE.
Steve

Hey Scirocco,
Tomorrow I will try what you said about "Adjust the idle rev and pilots screws (1 and 1/2 out) without throttle cable in touch" because I believe it is cable issue now, hopefully, it is. The carbs were backfiring just a little but I was low on gas, so there is most likely no problem there.

Hey Ed,
I know that 1000 +/- 100 is a great idle, I was trying to say that the engine was idling around 1300 rpms before, but in the video when I started the bike the motor jumped up to 2000ish rpms and I adjusted it back to normal, however, that adjustment would of been to low before when the bike was running.

SWest,

I also check the spark advance, tomorrow too. And I'll make another video explaining everything. Because I don't think it is lubricated

Togoster,

I knew this was going to be hard, but I wasn't expecting any carburetor problem only electrical. Hey, at least no engine problems, maybe besides the valve clearances.
It's only been 3 months since I bought my first bike, also a non-working bike. I had no idea what I was doing. But since that, it already has 3,000 miles added. I learned so much about motorcycles.

Hopefully, my next bike will be fuel injected

Thanks, everyone and have a blessed night.

Guys, are we overlooking the obvious here? When cold and starting with the choke these bikes always rev high at idle. Backing off the choke gradually until warm to get a reasonable idle is the normal practice. Once warm the choke can be backed off entirely.
Idle should be set approx. 1000 rpm when warm and you shouldn't need to touch it again.

As the OP is new to bikes, especially old tech bikes, maybe he is expecting it to be turn key ready to roll like a modern car/bike?

You're right. With the stock carbs it had to have choke for about 30 seconds before it would idle depending how cold it was. The later models were even more cold blooded. The more I wean out my 33's the more I need the choke to start it. That's a good thing.
Steve

Okay, so this morning when I woke up. I went into the garage, If you remember the last video I uploaded the bike was idle good, no problems. Now I can't even get the bike start this morning. I will have to mess with the idle screw again to start up the engine, which I haven't done yet.

And for my other bike the kz550, I also had to use the choke for 30 seconds before it idles okay and then ride it for 2-4 mins before it idle perfect. You gotta to love old bike.
Today, I don't have time to work on the kz750, have work all day.

And If anyone lives in the Chicagoland metropolitan area, let me know. I am more western suburbs.

And the last thing is the the carbs are leaking gas out of those long tubes (sorry don't know the name for them) , so now I will have to adjust the float level , it funny because it wasn't doing that yesterday.

Lastly, thanks for all the advice

If it's flooding out of the overflows do the sniff test on the oil. That could be why it's not starting. As with most old bikes you have to do and undo what the PO did or didn't do. One thing at a time.
Steve

Your_Boy_Yuriy wrote: .....................And the last thing is the the carbs are leaking gas out of those long tubes (sorry don't know the name for them) , so now I will have to adjust the float level , it funny because it wasn't doing that yesterday....

Regarding the carb overflow -

Fuel coming out of the overflow hose (the little hose on the bottom of the carb) is the common symptom of the 3 possible problems described below. Remember - NO SMOKING or other activities that could ignite the fuel while working on carbs!

The float valve is not sealing. This may be (and probably is) just a matter of some minor dirt in the float valve and is very simple to remedy and can be done with the carbs still on the bike. Turn off fuel; drain carb by loosening big brass screw near bottom; and remove the 4 little screws on the bottom of the carb bowl. This will enable you to remove the carb bowl. You will then see the float. If you carefully remove the float you will see a stubby little needle that mates with a brass orifice; together, these two pieces are the float valve. Assuming there is no obvious damage to the needle or seat, use a Q-tip and some carb cleaner to clean the seat of the orifice and the needle. Be careful not to bend the tang that is attached to the float. This tang is the piece that the bottom of the float valve needle rests upon, and it determines the fuel level in the bowl, so bending it will change the fuel level. With the float valve cleaned it should no longer leak. To prevent a re-occurrence a quality inline fuel filter should be installed between the fuel tank and carbs. If there was damage the needle and seat should be replaced as a set; they are available.

The brass overflow tube inside the carb bowl is damaged. When you remove the carb bowl you will see a brass tube attached inside and rising toward the top of the bowl. This is the overflow tube and it leads directly to the overflow nipple on the bottom of the carb. Normally, the fuel level within the bowl rises somewhat close to the top of this tube. If the tube becomes cracked or separates from the bottom of the carb bowl fuel will flow through it and out through the overflow hose. Checking the condition of the tube is very easy after you have removed the carb bowl from the carb. Simply hold the bowl level and fill it up near the top of the tube with water or alcohol and see if it leaks. A slight crack in the brass overflow tube can be difficult to find. You can connect a rubber tube to the overflow nipple, fill the bowl with water, put finger over the open end of the brass overflow tube and blow in the rubber end and look for bubbles. If it does the best remedy is to replace it although some folks have found creative ways to repair them.

The fuel level is set too high. This condition occurs when someone has bent the float tang as mentioned above. This condition can be checked using what is referred to as the "clear tube test." The test involves attaching one end of a clear piece of flexible tubing to the carb drain hole and holding the other end of the tube above the bowl/carb joint. When the fuel is turned on it should rise in the tube to a level 2.5 - 4.5 mm below the bowl/carb joint. If the fuel rises higher than that level it may run into the cylinders or over the upper end of the brass overflow inside the carb bowl (mentioned above) in which case it will run out the overflow hose. This condition is corrected by removing the float and gently bending the tang to raise the float valve needle position. Doing this may take several tries before achieving the desired fuel level.

Correcting each of these three conditions involves removing the carb bowl. This task can be made easier if a short screwdriver bit is used, and depending on which carb you are fixing a mirror may help you locate the screws on the bottom of the carb bowl. Also, it is not a bad idea to have a new carb bowl gasket available in case the old gasket is damaged while removing the carb bowl. Ed

All of the advice above are all possibilities as to the problem. The only shortcut I've ever found to a better running motor other than really understanding the entire process ( which I'm not claiming i do) and going through the whole procedure is a bottle of Gumout and yeah, have some gaskets around if you pull the float bowls. Draining the float bowls is a good way to see what kind of crap is in them. These old bikes are just that ... Old . It's cool to see someone starting out on the path.

Ever read the book, "Zen and the Art of Motorcycle Maintenance" , Y-B-Y?

Oh, sorry, I do remember now that the bowls where clean.

What can i say?

I'm old too