KLR 250 issues

I have a little KLR that is having issues. It was running fine and then I bought a DRZ and haven't really driven the KLR. I had a guy that wanted to buy it after it had set up for two months. The bike starts well. It revs up. It seems to be ok until you are going down the road. Under a load/accelerating after third gear the motor boggs down. Could it be an ignition issue? Could it be a carburetor issue? Any ideas?

Drain all the fuel and clean the tank,petcock and carb. It is probably old stale fuel or dirt in the carb.

little tiny jets in that carb, the slightest deposits in them will have a very noticeable effect especially when you factor in that stock it is jetted on the lean side already.

carb needs to come off and be cleaned. tank drained and fresh gas back in.

Did you turn off the gas and drain the carb, before you stop riding it?

I ran it dry. Then flushed the tank before I parked it.

You could try adding some SEA FOAM (available at auto parts stores) to some fresh gas and run it. A good last ditch effort before removing carbs. It might not work, but it's easy.