1980 KZ750 Twin

Hello I've been working on this KZ750 and I had a question i needed to ask. The tank petcock has two outlets, are these two independent outlets for each individual carb or is one an overflow outlet? The fuel lines didn't come with the bike so I'm trying to figure out how everything fits together. Also if each line goes to each carb is there an inline fuel filter for these bikes or is it a straight connection? Much appreciated.

The Bigger outlet runs down between carbs that feeds both carbs. The smaller of the 2 outlets on the petcock is for a vacumn connection that usually connects directly to one of the carb manifols for automatic fuel feed to the carbs. Normal position of the petcock is straight down for automatic operation. I would advise you to use an inline filter such as the clear glass type that can be disassembled for filter cleaning.

Is the petcock a vacuum style or manual style?

A manual petcock typically has two equally sized fuel outlets, both of which function the same, and with no smaller vacuum tube being involved.

A vacuum petcock will have one smaller outlet where the vacuum tube connects.

Where only one of two petcock fuel outlets is used for carbs having a single fuel inlet, the unused petcock fuel outlet may be capped off (a common vacuum plug works nicely).

Would assure no fuel reaches the carbs without first passing through an inline fuel filter.

Good Luck!

The two outlets are of equal size. I hooked them each up to each of the carbs and tried to start it but couldn't get her to turn over. I have good spark, fuel's getting to the carb, so I'm assuming the carb is still not completely cleaned...any other suggestions?

pull the plugs see if there wet looking then go to the basic starting full choke no throttle if it still wont start run a compression test 150 nominal 115 service limit if thats ok start checking pilot jets and passages

thanks buckinrut, checked compression and it's within range. Guess I'm back to cleaning the carb. Do you happen to know if the 750G twin carbs float bowl pin can just be pulled out to remove? What about the jets? Do i just unscrew them or is there a special way of removing them?