It will start with the choke but backfire? So. Let it backfire. Thats probably crap thats being burned. It will clear up.

 

it wont start at all.

 

i'm bout to hop on my bicycle (leg - powered) and go to discount auto parts. buy ignition fuse. probably because when i press ignition start button in my motorcycle, battery seems like its supply power to bike illuminating more than before.And sounds like eeeheheeeeheeeeheeehee.
No turn over.
backfire and scared me out of my garage. sounded like someone busted a cap in my ***.!!!

 

if you have a multimeter or voltmeter you can test the voltage at the battery terminals to see if you are getting the 12v you are supposed to. If not then your batt is messed up

 

I don't think it's electrical if he isn't smelling a whole ton of gas. Maybe it's fuel delivery that's what my guess would be. If it's cranking and all the lights are coming on then it's probably fuel related. Suck out the old gas if it's been sitting for years or something. I would say check the injectors and fuel pump but you have a carburator and I don't exactally know much about that, or much about anything for that matter. Good luck!!

Mike

 

the 1999 markings arent a big deal either. 1999 - 2000 F4 is the same and even most of it went onto the F4i (except FI and a few cosmetics).

 

i had that same problem when i had my 2000f4 it ended up being the cards being dirty, so i bought a can of carb cleaner and pulled the cards out and sprayed it down. once i did that it ran fine. its not hard to clean the carbs just thats time. if your gonna do it make sure the carbs on correctly or else you will lose compression and it wont run right. hope this helps.

 

heres a how to on cleaning your carbs
https://cbrforum.com/m_311016/tm.htm

 

bout to change the spark plugs. GOT ALL THE WAY DOWN PAST MY AIR FILTER AND REALIZED I NEED A SPECIFIC TOOL TO RELEASE PLUG FROM LOCKED POSITION.And it's at an angle so it seems i need a plug wrench only. there's a welded bar preventing me from using any other tools based on my mechanical visual fix up guide.

 

alott backfire could be a sparkplug issue too,