2008 wr250x 1500 miles sputters

Okay so I recently purchased a 2008 wr250x. Ive noticed while romping on the throttle at slow speed it wants to hiccup/sputter/studder. At idle ig revs up just fine. If I accelerate slow it runs perfect.

Here is the mods I've noticed that previous owner has done:
Smog block off plate
FMF PC4 slip on
Airbox Diaphragm removed
Flapper screwed down
EXUP cables removed but motor still there

Only thing that I've noticed is that it doesn't have the FMF programmer. (I will be purchasing within the next month.)

One last question; If I unscrew the flapper from being screwed down will it be safe ebough to drive until I get the FMF programmer?

Thanks guys for the help!

I would def get a programmer soon. With open exhaust and airbox, you should be adding some fuel to prevent from running lean. Programmer will also smooth out the bottom end jerkiness and any snap, fart, on decell.

I know it's needed ASAP. But if I unscrew the flapper until I get a programmer will it help? Or just leave it how it is?

Hmmm I think the flapper was a part of the road restrictions as far as choking it down. would be more concerned if the door was off or modded but I will let some one else chime in on this part.

mcdoudlehopper wrote:

Hmmm I think the flapper was a part of the road restrictions as far as choking it down. would be more concerned if the door was off or modded but I will let some one else chime in on this part.

Well the door is modded. It's screwed down and the Diaphragm has been removed completely.

Think we are talking about dif things. I meant either completely removing the side door or drilling large holes in it.

Bump.. Anyone know?

What's the air filter look like?
How old is the fuel in the tank?
What's the condition of the battery?
Was the bike just sitting around for a while before you bought it?

YZEtc wrote:

What's the air filter look like?
How old is the fuel in the tank?
What's the condition of the battery?
Was the bike just sitting around for a while before you bought it?

Just put fresh fuel In.
Honestly it looks like oem (says "made in Japan") but it cranks just fine.
He only drove it 150 miles in 3 years.

I'd take care of some basic stuff.

Myself, I'd remove the fuel tank from the bike, turn it upside-down, and get all of what's in there out.
I'd then pour in a little bit of fresh fuel and repeat.
I'd then put the fuel tank back in place and then add some fresh fuel to run the bike with.

I'd remove the battery and take it to a motorcycle dealer with a MOTORCYCLE battery tester.
I'd have the battery tested on one of these devices.

Air filter condition?

YZEtc wrote:

I'd take care of some basic stuff.

Myself, I'd remove the fuel tank from the bike, turn it upside-down, and get all of what's in there out.
I'd then pour in a little bit of fresh fuel and repeat.
I'd then put the fuel tank back in place and then add some fresh fuel to run the bike with.

I'd remove the battery and take it to a motorcycle dealer with a MOTORCYCLE battery tester.
I'd have the battery tested on one of these devices.

Air filter condition?

I've flushed the fuel completely. I thought it was because it has all these mods without the programmer. (Opened air box mod)

Air filter looks brand new.
I mean the whole bike is absolutely MINT.

Jremeee wrote:

YZEtc wrote:

What's the air filter look like?
How old is the fuel in the tank?
What's the condition of the battery?
Was the bike just sitting around for a while before you bought it?

Just put fresh fuel In.
Honestly it looks like oem (says "made in Japan") but it cranks just fine.
He only drove it 150 miles in 3 years.

If it was me I'd change the air filter for a high flow aftermarket one because it could be original and brake down sucking pieces into the motor. Also change the plug unknown age and it's a bitch to get to on the trail. But I'd say when you add the programmer and use the settings recommended in the fuel map section the bog will probably go away but hard to know without it. Start with the basic maintenance and see if it helps then see what difference the programmer makes. You'll like how a fuel programmer wakes it up.

There is a fuel filter in the fuel pump assembly as well I'm fairly certain. Might be worth checking and cleaning it. Also a pain having to take the tank off.

speersie wrote:

Jremeee wrote:

YZEtc wrote:

What's the air filter look like?
How old is the fuel in the tank?
What's the condition of the battery?
Was the bike just sitting around for a while before you bought it?

Just put fresh fuel In.
Honestly it looks like oem (says "made in Japan") but it cranks just fine.
He only drove it 150 miles in 3 years.

If it was me I'd change the air filter for a high flow aftermarket one because it could be original and brake down sucking pieces into the motor. Also change the plug unknown age and it's a bitch to get to on the trail. But I'd say when you add the programmer and use the settings recommended in the fuel map section the bog will probably go away but hard to know without it. Start with the basic maintenance and see if it helps then see what difference the programmer makes. You'll like how a fuel programmer wakes it up.

It's not really a bog. It's kind of like a studder or burp. But only if I romp on it from idle. It i take off easy it doesn't do it. It kinda feels like it's getting too much fuel.

Sounds like the bike is running lean when you SNAP on it hard. it's getting the air but not enough fuel which is why it burps. if you accelerate smoothly throughout the RPM range it's fine? My guess is add a Fuel Programmer as mentioned above and you should be fine.

Caldsy wrote:

Sounds like the bike is running lean when you SNAP on it hard.  it's getting the air but not enough fuel which is why it burps.  if you accelerate smoothly throughout the RPM range it's fine?  My guess is add a Fuel Programmer as mentioned above and you should be fine.

Thanks. I think I'm going to unscrew the flapper until the programmer gets here (ordering this weekend) just so maybe it don't get as much air when I snap the throttle.

Jremeee wrote:

Thanks. I think I'm going to unscrew the flapper until the programmer gets here (ordering this weekend) just so maybe it don't get as much air when I snap the throttle.

I wouldn't be doing that unless you still have the diaphragm installed which I doubt. You don't want to close off the air completely.

Hey there smartazz, get that thing running properly with a programmer and take a ride up here to CT so I can show you how to get that thing dirty.:)

Adam.

wristpin wrote:

Hey there smartazz, get that thing running properly with a programmer and take a ride up here to CT so I can show you how to get that thing dirty.:)

Adam.

Where is CT? Charleston?

There must be another Jeremy in myrtle beach with a WR. Carry on.

wristpin wrote:

There must be another Jeremy in myrtle beach with a WR.    Carry on.

I just bought my wrx Sunday. If there is another Jeremy in mb with a wr I need to meet him. I need people to ride with lol

IMHO the EFI is very rich on these bike in the power range, hurting it with just a muffler and airbox mods is VERY unlikely. Where they are lean is in the light throttle settings which causes the stumble. Do the CO adjustment (free) set the idle speed correctly (free) and I'll bet you'll be happy.

Jremeee wrote:

Okay so I recently purchased a 2008 wr250x.

With this being said, read up on the tank removal vause ive heard of guys breaking off the nipple to the fuel pump. You don't want to do that.

mcdoudlehopper wrote:

With this being said, read up on the tank removal vause ive heard of guys breaking off the nipple to the fuel pump. You don't want to do that.

This had me really worried went I installed my PCV. It's not that bad at all and is important to learn. Taking the tank off will be necessary or a hell of a lot easier many times during maintenance. I think it's more about being careful and safe placement of the tank taking into account the fuel pump connector.

I have a question... Is the bike completely up to temp when it sputters? These bikes dont like to be run hard untill they're warmed up.

Mine will sputter if I ride it hard before its completely warmed up and I have a fmf programmer.

You can adjust the CO setting and make it richer off idle, I had to do this to mine even with the programmer.

It should run fine with a pipe, stock airbox, adjusted CO and no programmer.