sv starting sputtering then dying even on choke

I've searched but I can't seem to find somebody else with the same problem...

My bike is parked outside with no cover, and I just recently added on a remus high mount slip on. It has been raining lately but it has never been a problem starting up, only the front cylinder would die when i ride it in the rain.

However when I started it today, it started up fine and I put the choke on to warm it up then it would start sputtering the rpms would drop down 1500 rpms or so for 5 seconds then snap back up to where i set the choke. I'm 100% sure the spark plugs aren't wet, since I dried them out a couple days ago and haven't ridden the bike since. Everything else is clean carbs, air filter, etc. I am baffled to why the bike is sputtering since the bike always starts up no problem.

any ideas?