Hi, I have a '99 Honda CBR 600 F4 and I am pulling it out of the garage after being stored away for the winter. I pulled apart the carbs and gave them a nice clean, put the bike back together, and then it wouldn't start. I gave it a few more tries before it came to life with the choke open for a little bit before it died. Then I couldn't get it to start for more than maybe a second before it died.

I pulled the carbs apart again and noticed some black flake kinda of things on the butterfly valve and going into the engine. I have no idea what it could be but it wasn't there before. I cleaned it up and put the bike together again to find that it was doing the same exact thing except this time while trying to start it made aloud pop that scared me. I believe it was do to unburnt fuel in the cylinders combusting since I tried many times to start it.

When I cleaned the carbs I checked the floats in the bowels, the mixture needle, I thoroughly cleaned the jets, and I scrubbed the housing. I also checked the fuel filter and the air box and are both fine. The bike has all new oil and filter, coolant, and the gas had fuel stabilizer in it before I stored it away.

When I put the bike away I was starting to experience the bike not wanting to idle without the choke open but now it's not running with anything.

I'm not sure what else to do at this point. Any suggestions as to what this could be? Thanks!