250-500cc 250-300 differences (not performance)

I have read a lot on here about problems and tips. But it seems like most are for the 300. I have a 2011 Wr 250. What are the differences in the 2 bikes? Other than bore size. Carborator? Reed Valves? Clutch cable? What did they change on the 250 since 2011 or is the 2013 the same bike?
Not having any problems, just curious but I thought they were 99.9 % the same. I would like to know what to do about the clutch cable. I cant start the bike in gear to save my life.

the original 300 was a kit you bought from the dealer to replace the cylinder piston etc. like the 144 kit for the 125
they were so popular they built them as original factory bikes

A number of us have replaced the stock clutch cable with a Motion Pro Terminator cable with very good results. Just call motion pro and order one, make sure to order the Terminator not a stock replacement. They can even make custom lengths if you need. I ended up ordering a shorter one when I replaced the stock clutch lever with an ASV. The stock length was a bit too long and I had to crank the adjusters all the way to take up the slack.

Thanks for the info. I got to do something about the clutch cable. I will order the Terminator soon. As far as the bike goes I havent did anything to it and it runs great. Does seem to lose power if you dont shift soon enough, compared to the YZ250 I came off of. Only seems to be a problem in sand or very loose dirt.