If you're also running Off, this is the way to go.
If you want to run off-road with 2007 WR250X, OEM is the safest choice. Just recently, at Mr. Webig, I bought YOSHIMURARs4J (Japanese Government Approved Exhaust System) As a result, the combination with the OEM exhaust pipe is the most suitable for our power characteristics and the pickup and power in the whole range is very good. (aisCut and intake Solenoid removal only, NORMALecu) Then you can get a good lap time, so I greedily added a K&N Air Filter to compensate for the fuel. (This is as far as you can go with Meter. By the way +4) However, if you also run off the road, the wet air filter will cause a lot of dust and sand to enter the air filter. (MOTARDCourse has a Large Outline DirtSection, right?) We strongly recommend the OEM Air Filter for those who do not want to rewrite the ecu.
Pickup is a little Large person, but with the external Air Filter, it seems that fuel is a little thin only with Meter correction, and when it returns from k&n to OEM, After has decreased. After all, I think that the OEM Air Filter is more compatible with NORMALecu.