Can't get my bike to start!! Help please!

Ok..just purchased my first bike. 1977 KZ400. Worked alright when I went to buy it but it needed to have the throttle revved to stay running. Since I got it home, it will not start at all. Here is what I have done so far (remember that I am a girl newbie!)... removed and cleaned the carbs, cleaned the gas tank, replaced the plastic fuel filters on the line from the petcock to the carbs, gave it an oil change and checked the air filter.

It makes the noise like it is going to start, but will not catch. The previous owner did put new spark plugs in. Sorry if I am not using the correct terms! I do not see any fuel going through the fuel filters. I noticed this before I replaced them as well. I have taken the petcock apart and blew it out with air. No clogs. I need the screen replaced in it but can not find the part through my Kawasaki dealer.

Any other suggestions? I could take it to someone but I would really like to learn how to do it myself rather than relying others! Thanks in advance for your help.

Getting Frustrated...Tara

You say you cleaned the Carbs, was compressed air with carb cleaner used? Blown through all the passages? Did you set the Fuel level/ float height?
Then do you have the Factory stock Airbox, or individual/ Pod air filters?
Ignition system, have you checked the Points? They may not have enough gap, could be badly pitted, etc. Does it have a bright blue spark, when you have the plugs out laying against the head?
Make sure fuel is coming out of the petcock, and the choke on, don't apply throttle, then try to start.

Yes I cleaned with air and carb cleaner. I did not set the float level because I thought that it was probably right. I will check it though.
It is a factory air box.
I will also check the Points and let you know.
I know that fuel is coming out of the petcock, but it isn't going through the lines to the fuel filter.

I will check the above things out and let you know. Thanks for your help!

The fuel is coming out of the Petcock, but is not going down the lines to the carbs?
Can you loosen the drain screws on the bowls and have fuel come out?
The Petcock, what Positions are there? On-OFF-RES, Or ON-PRIME-RES?

Correct. If I take the hose off of the petcock, the fuel drains. It is not getting through the lines to the fuel filter or the carbs. Does not drain from the carb.

I have On Off Res. That is functioning fine.

I agree.. I would start by loosening the float bowl drain screws and see if you have fuel in each of the float bowls. If there is no fuel in the bowls then you have an issue with the petcock or fuel filters restricting the fuel flow. Also the petcock is probably vacuum controlled so that may have something to do with the issue.

If you have fuel flow then the next thing to check is the plugs for proper spark.

And what do you mean by it tries to start but wont catch? Is the engine turning over or do you just hear a clicking noise and no engine rotation? If the engine isnt turning over then it could be as simple as a battery thats not putting out enough cold cranking amps.

Take the line off where it goes into the carbs and turn on the fuel,it should come out. After that, fuel flows, then maybe you have floats in wrong?
Or if it doesn't flow, what filter? One for a gravity flow system/ motorcycle?

tarav wrote: ...If I take the hose off of the petcock, the fuel drains. It is not getting through the lines to the fuel filter or the carbs. Does not drain from the carb.
I have On Off Res. That is functioning fine.

If fuel flows from the petcock, but stops inside the line before reaching the fuel filter, would suspect the line is either kinked or internally obstructed.

A seriously dirty in-line fuel filter may also block fuel flow.

Good Fortune!