ok ive been havin problems finding out out wat is wrong with my 99 f4 for months. few months ago i was ridin with some friends to a bbq, when it was time to leave my bike wouldnt start up. so i had to run start it. only way i could keep it on is keep the throttle open at all times or it idled down and shut up. got home and it wouldnt start back up. when it cooled down it would start up than shut off wen it started warming up. i left it alone for a while, had carbs cleaned yesterday and it started up like new, drove it home,next day starts then heats up and shuts off. also had battery charged.
im thinking it has something to do with the fuel pump, but when i turn the key the punp kicks over. strange thing is i took the the tank completely off today and started it up, it actually ran fine. put the tank back on and it wont start up...what the heck...please any ideas would be greatly appreciated

 

Sounds like classic F4 charging problems - how long did you charge the battery? When you try to start it with the starter do all the lights dim but you hear nothing, save perhaps an initial click? If so then you could be looking at a new battery or investigating charging system components.

The other thing is that hot problems can be valves - when were they last adjusted?

 

sounds like the R/R or maybe the stator? i'm leanin more towards the rectifier.

 

You could have multiple problems. You should have your battery load tested somewhere, most parts stores will do it for free. Assuming you have a good battery, charge it (very slowly). Need to start with a good, fully charged battery as a base and troubleshoot from there. There is a good stick thread about troubleshooting the charging system, in here or GT, I don't remember.