Sounds like you've got a plugged idle circuit/jet. How long has it been since you've cracked open the carb?
Ticking is most likely valve issues, which dirt bikes require checking every 100 hours or so. That might also explain loss of compression and why it won't idle, if your valve timing is off far enough.
Tackle the valves first if it's been a while, that will do the most damage to the bike if they are out of spec; hopefully, you're not getting piston slap.
Also, could be slack on the timing chain - have you adjusted the timing chain recently?
2009 Aprilia Tuono - Ginger
2001 XR650R BRP (Big Red Pig)
2006 Honda 599 - Ex wrecked it :-D
2007 Honda CB900F (sold)
2006 Honda VTX 1300C (sold)