Reliability impact of FMF exhaust + programmer

Hey folks, new here. I don't yet have a WR250R, but I'm shopping for one and found a clean copy with very few miles.

I generally prefer to buy vehicles stock, but this particular bike has an FMF header, pipe, and programmer installed.

My question: Does this modification have any impact on the reliability of the WR250R? Any change in regular maintenance intervals because of the modification, or anything else I should know about? I understand it's a very common mod, and the seller even has the stock parts so I could return it to stock if I want. I just don't know much about it.

Thanks for any help!

Practically speaking, no, except for repacking the muffler once in a blue moon (I do mine once a year).
I also feel those items are worth having on the bike, as both my WR250R and WR250X had them.

Thanks for the response, it's reassuring.

Depending on which FmF pipe (Q4 or Powercore) is on the bike noise might be your biggest concern.

In terms of reliability and/or maintenance - no effects or changes that aren't in your favor.

If you're also getting the stock items, I don't see the issue.
Try the bike both ways and see which one you like best.

The only thing I would think that may impact reliability and performance is how the FMF programmer was programmed.

When I first did mine I kept having engine cut outs at mild throttle application around 50 to 60 mph even though I set it per their instructions.

Later I read in the Forum that the #5 setting (I think) needed to be set at 6 or higher to avoid that issue. When I did that all seemed well but my fuel economy took a nose dive which led me to believe I was running rich. Actually it was down as soon as I installed the FMF programmer not because of the changing the #5 setting.

In my mind unless you have a dyno or exhaust gas analyzer then setting up the programmer is all guess work and if you guess right then things should be good. Guess wrong and then things will not be as good.

motokid wrote:

If you're also getting the stock items, I don't see the issue.
Try the bike both ways and see which one you like best.

How easy is it to return to stock? Does the programmer need to be returned to factory settings before disconnecting it, or does disconnecting it automatically return the FI settings to stock? I'm not worried about unbolting / bolting to swap the header and pipes, but FI and electronics are an enigma to me.

MRSallee wrote:

motokid wrote:

If you're also getting the stock items, I don't see the issue.
Try the bike both ways and see which one you like best.

How easy is it to return to stock? Does the programmer need to be returned to factory settings before disconnecting it, or does disconnecting it automatically return the FI settings to stock? I'm not worried about unbolting / bolting to swap the header and pipes, but FI and electronics are an enigma to me.

The programmer is easy to remove.

There is a connector from the controller to the injector and another connector from the bike ECU (normally would go on the injector) to the controller. Remove these two connectors and plug the ECU connector directly into the injector (stock setup). I think you may have to remove a negative ground to the battery as well.

The one thing I would do before pulling the programmer is to write down the settings since I am not sure how long it will retain those settings once removed from the bike.

Do you know what type of programmer that you have? The above are based on a FMF programmer. If you have a Power Commander then there are a couple of other connectors that you will need to play with that interface with the TPS.

rsteiger wrote:

Do you know what type of programmer that you have?

The programmer on the bike I'm looking at is an FMF.