I'm a noob at this stuff so criticize me if you must. This seems like a common problem but me and my riding group cannot figure it out. We believe it is the dirty carbs. We took off the air filter and put in starter fluid so that the bike would turn on and it did, but only for a couple of seconds before it died out again. So on the safe side I know I bought a bike that is still alive and awaiting to be alive again.

It has a new 100% charged battery.
Spark plugs are in great condition.
Fuel lines were cleaned.

Is there any carb cleaning specific threads for the f3 anyone can redirect me to?

What other problems can lead to the bike cranking but not staying on?

 

Carbs are a good place to start. I don't have audio here at work, so I can't tell which videos are good. This one LOOKS ok.
Carb cleaning is easy. Just take your time and don't ham fist it and you will be good. Compressed air (or a duster can) with some carb cleaner is a must.

 

So its flooding then? You didnt really specify. Lines I assume you are saying the tank to carb? Do you know if its making it to the cylinder? Did you pull a plug and check? Smell fuel out exhaust? Need more info here please.

-Poss