DE Modding my 2018 WR250r

Hello, I recently bought a 2018 WR250R that has many of the common bolt on mods. It came with the stock parts that were removed (Hope I have them all). It has the Full FMF Q4 Exhaust with FMF Power-Bomb Header * Graves AIS Block off kit & Grave EXUP eliminator * EJK Fuel Programmer . I'd like to put the stock pipe back on. Do I need to install the removed EXUP components and is it preferable? Should I keep the EJK fuel programmer on the stock bike? I'll probably sell off what I don't use. I need the bike quiet for what I want to get out of it.
Also, is it tricky reinstalling these components? I don't have the factory service manual yet, so no idea how it all hooks up.
Tia

For what it is worth I like the EXUP on the bike for slow speed woods riding. It does provide a nice little torque bump in the low RPM range. However, if you are riding it in a more open environment you may not benefit from adding it back on. Get yourself a Service Manual since that will come in handy on several things. Most are available in an electronic format.

The only thing I would concern myself about is adding the AIS back on the bike. The stock muffler has a catalytic converter in the assembly - the AIS system provides fresh air for the catalytic to function properly. If it is not in place you may be at risk of plugging up the catalytic over time. In my case I cut open the exhaust and removed the catalytic converter.

rsteiger wrote:

For what it is worth I like the EXUP on the bike for slow speed woods riding.  It does provide a nice little torque bump in the low RPM range.  However, if you are riding it in a more open environment you may not benefit from adding it back on.  Get yourself a Service Manual since that will come in handy on several things.  Most are available in an electronic format.

The only thing I would concern myself about is adding the AIS back on the bike.  The stock muffler has a catalytic converter in the assembly - the AIS system provides fresh air for the catalytic to function properly.  If it is not in place you may be at risk of plugging up the catalytic over time.  In my case I cut open the exhaust and removed the catalytic converter.

Thanks for that info. Will probably put it all back to stock and keep the cat converter happy. Is the fuel programmer smoke and mirrors on a stock bike, or does it improve performance and not harm reliability in your opinion?

Nicad wrote:

rsteiger wrote:

For what it is worth I like the EXUP on the bike for slow speed woods riding.  It does provide a nice little torque bump in the low RPM range.  However, if you are riding it in a more open environment you may not benefit from adding it back on.  Get yourself a Service Manual since that will come in handy on several things.  Most are available in an electronic format.

The only thing I would concern myself about is adding the AIS back on the bike.  The stock muffler has a catalytic converter in the assembly - the AIS system provides fresh air for the catalytic to function properly.  If it is not in place you may be at risk of plugging up the catalytic over time.  In my case I cut open the exhaust and removed the catalytic converter.

Thanks for that info. Will probably put it all back to stock and keep the cat converter happy. Is the fuel programmer smoke and mirrors on a stock bike, or does it improve performance and not harm reliability in your opinion?

I have played around with a lot of different mods on my WR250R but the reality is a lot of the benefit or lack of benefit depends a great deal on how you use the bike.

I had a PCV with the airbox mods and custom free flowing exhaust with a custom map developed during several dyno sessions. The end result was the bike was noticeably faster on the Interstate - I topped out at a GPS indicated 93mph. However, it was not so happy running down a tight woods trail - it definitely lacked some low end grunt that was there in it's stock form.

In the end I pretty much returned it to stock since I tend to ride the bike in off pavement scenarios and I don't really race it - I ride it for enjoyment and I enjoyed it better in the stock setup.

So in my case the engine mods were not really worth it and actually hurt the performance of the bike for how I ride it.

However, the suspension mods made a big impact for me on the trails. The GoRace solution worked very well for me and how I ride the bike.

That being said, if you are using the bike more as a motard then I think there is something to be gained from the engine mods... really depends on how you are going to use the bike.