Motorcycle still wont start?

since i got the bike last year i had the same problem, first i was getting some weird smell from the back of my bike, took it in and they changed a part in the back left side of my bike(voltage regulator), after that i changed my battery but i still have the same problem when i charge the bike and start it it runs fine when i turn it off or park it it want start again, i have to put it on charger to start it , my head lights sometimes turn of when i first star the bike when i press my brake or clutch and hold it the complete light system start loosing voltage i mean the neutral light, headlight everything and when i let it go they start getting their power again, after jump starting it so many times, now i have another problem with no key, kill switch off when i connect the cables to jump start it , it starts making that noise like it wonts to start , i need help? one guy told me he is 100 precent sure its the voltage regulator again?

thanks , one thing ,my manual says the voltage regulator is the rectifier, i have 1993 fzr yamaha

I agree, it sounds like a charging problem. Let me explain the system.
1st The engine spins magnets of the alternator/stator past a wire spool creating a magnetic field that creates AC voltage in a "Y" or triple formation
2nd This AC voltage is then "rectified" thru a rectifier made of 3 diodes & turns it into DC ( like a check valve is to water)
3rd The DC voltage is then regulated to control the DC voltage from getting to high ( above 13 or so volts)

It's not you regulator, the guy is 100% wrong. It's either the diodes in your rectifier are open or shorted, or the wires in your stator are either open or shorted.
Do you have a buddy who knows how to work a meter & a schematic of your system , it can be figured out pretty quickly.
If you want an honest shoot from the hip opinion, go for the rectifier, The rectifier is probably your cheaper part of the two.

MOST LIKELY Regulator rectifier.... OR on some bikes RECTIFIER.... (they have a separate regulator mostly OLDER bikes ) why they have DIODES a diode is a little ONE WAY gate the purpose is so the voltage will not constantly have a path to ground (the Frame and battery).
when jump starting you should NEVER have the car running as it puts out too many amps and can BLOW OUT the DIODES..... This applies to STARTER/CHARGERS Don't use the START portion of a charger.
that noise is Y
our Starter BUTTON is STUCK
OR
YOUR STARTER Relay is STUCK
shut tap on it.... OR you are putting your jumper battery to the starter Relay and you are going to the WRONG side (the side that leads Directly to the starter is the WRONG side)
34 years professional motorcycle mechanic
Gary Mares
http://www.marescycle.com
(630) 963-7720

From your description it sounds more like a charging system problem (alternator or stator), although it could be shorting out the voltage regulator too.

Trouble shooting electrical problems can be tough, and expensive, but I think if you take it to a qualified mechanic, they should be able to pinpoint the problem.