Motorcycle Repair: gas in airbox, starter fluid, airbox

Question
I have a 1991 Yamaha yfm250b that was running well until yesterday--just quit and would not start.  Gas was in the airbox.  Took the carb apart and cleaned it, put it back on and still the same problem.  Starter fluid doesn't work.  Also, compression seems almost non-existent, but the engine has only 130 miles on the ring job.  Is it a stuck valve, and how can I fix this?  Thanks for your insight.

Answer
Hi David.

 How clean is the air filter?  A severely dirty air filter can cause all of those issues and more.
 As far as compression, if you haven't checked compression with a compression testor, then you do not know if it is getting a loss of compression.
 There is the possibility of the valve timing being off as well.

 I seriously doubt that the carb is the issue, or ever was.

 If the air filter is clean, or reasonably new and clean, then get out the repair manual and approach the other possibilities, or get it to a shop to be looked at by a properly trained mechanic.

Good luck and ride safe.
FALCON