The 2013 and newer fuel Inj XT250 run well but they can run a little better.
I installed a Dyno Jet Power Commander FC fuel control specific for the 2013 and newer fuel Inj bikes. The controller comes with a map to match the stock configuration of the XT250 and three dip switches to add fuel +/- to the low,mid or high range. The XT250 just plain ran better and smoother stock with the configured map from Dyno Jet doing nothing other than installing it. ( With no other mods this is a perfect set up for stock)
(Note I wanted to keep the bike quiet left stock stock exhaust on bike)
More power can be made though. It is very easy to do with the Power Commander FC module. (The weak spot on the XT250 is the air box restrictions)
What I did to make even more noticeable low and mid power and smooth top end power. ( The XT250 is a low mid torque designed bike from the factory)
Step 1. I added a K&N factory replacement air filter.
Step 2. I purchased another air box lid and installed a 1" uni air box filter plug into the lid between the main brace that holds the filter down in place (note this is a very precise and tight fit to install this 1" filter plug as it just barely fits) This added more air to the air box (not much more air is needed)
Step 3. I adjusted the fuel controller low,mid and High as needed to run correctly. The XT250 runs great and has more power and is still quiet for trail and street riding.
(NOTE)
Setting ended up being stock pipe, Power Commander FC XT250 fuel controller 2013 & newer setting = low dip switch at +1 Mid dip switch at +2 High dip switch at +3,(These setting of course could and may differ on another bike but this fuel controler is very easy to tune. You can also use your PC for more precise tuning to the fuel curve if needed) K&N factory replacement air filter, factory air box lid with added 1" diameter Uni filter air box plug added to lid for more air to air box.
I really like the way my 2013 XT250 performs now.
Power Commander $199.00, K&N filter $45.00, extra air box lid $8.00, Uni 1" air filter box plugs pack of 6 $12.00
Happy Riding To All,

Bill G