Bike wants to stall around 3500 rpm

[Dkm0130]

Hey guys. I am brand new to SECA's. I bought a 92 XJ600 a couple weeks ago as a commuter. I just moved to Florida so I wanted to get something that won't drain all my money getting me around. So I have been riding it for about 2 weeks with no issues and have loved it then the other day after getting rained on for a few hours I went out and started it up to go to work. It started and idled fine but then when I put it in gear and started to take off it bogged down and died. I started it again and tried the throttle and it wouldn't get over 3500 rpm. I figured that because it ran fine the night before there might just be water in the fuel or something. This morning I drained the tank and float bowls and then refilled them both. I checked the air filter and it was fine. Then it wouldn't even start. So I pulled the plugs and they were a little dirty so i just changed them. I got it to start again but the highest I could get the rpms was 4500 right after I start it and then around 3500 the other times I try. Any ideas on what might be the problem? I'm not very experienced with working on bikes and I'm a little lost. Thanks.