Jetting issues? Tps? WR250F

christiande
Posts
3
Joined
5/27/2021
Location
Spokane, WA US
2009 wr250f with a rekluse z start auto and an fmf slip on

38 pilot jet
Aftermarket fuel screw 0 turns out
Jet needle on leanest setting at highest notch
170 main jet
Altitude 1800-4500 feet north Idaho/eastern Washington
Temperature 50-80 degrees Fahrenheit

I picked this bike up a couple weeks back and just can’t seem to get it tuned right. I’m experiencing what I think is a rich bog through each gear. There is also a pretty bad stutter/hesitation around mid-3/4 of the gears rpms. Mostly noticeable in first and second gear when slowly progressing through the gear around 1/8-1/4 throttle. When I fly through the gears full throttle the bike will power right through the sputter/hesitation but still feels a bit low/boggy. There is no popping coming from the exhaust on decel.
My brother has a 2007 wr250f with an fmf slip on and I used his main jet(162) and jet needle (four notches down I believe) and this didn’t seem to really help at all.
I’ve tried to read through some forums regarding these issues with this bike and it seems like a lot of people have unplugged their tps to get rid of the problem. When I unplug mine it definitely helps quite a bit but idle is still a bit rough and power isn’t as crisp as I would like. Definitely off from my brothers WR. I would like to be able to leave the tps plugged in and not just put a band aid over the problem. First plug I pulled after buying the bike was very black. I swapped that out when I got the bike and recently pulled the new plug and that was starting to turn a dry black as well.

For the pilot circuit it will fire right up without any choke and the reason the fuel screw is turned all the way in is because when I try to turn it out at all the idle gets worse. My understanding is when this happens I need to drop a pilot size but 38 already seems pretty lean.

Went through recently and cleaned the carb which was a massive pain in the ass on this model and my buddy mentioned that the float height was off and had adjusted that a bit. He didn’t measure the adjustment simply eyeballed it. So I’m thinking that probably wouldn’t be a bad place to start for the idle circuit but the bog/hesitation was there before the carb cleaning.

Any insights/pointers as to what to try next? Running out of ideas here.



|
LuiesMaes
Posts
79
Joined
9/1/2020
Location
Pueblo, CO US
5/27/2021 11:45pm
Record a video of the issue and throw it up on youtube and post the link here. .
LuiesMaes
Posts
79
Joined
9/1/2020
Location
Pueblo, CO US
5/27/2021 11:46pm
Also ask other people with similar bikes in your area what size jets they're running. Maybe on a local facebook group.
Paw Paw 271
Posts
3639
Joined
4/3/2013
Location
Benton, LA US
5/28/2021 11:07am
Fuel screw at "0" states that you are getting too much fuel from some where. It should be somewhere between 2 and 2 .5 turns out from seated. YOu don't need the TPS for this bike to run good, but you can set it at about .5 volts at idle. Check float setting and float needle seal.

Paw Paw
lhansen14
Posts
1
Joined
11/19/2023
Location
Ortonville , MI US
11/19/2023 12:01pm
2009 wr250f with a rekluse z start auto and an fmf slip on 38 pilot jet Aftermarket fuel screw 0 turns out Jet needle on leanest...
2009 wr250f with a rekluse z start auto and an fmf slip on

38 pilot jet
Aftermarket fuel screw 0 turns out
Jet needle on leanest setting at highest notch
170 main jet
Altitude 1800-4500 feet north Idaho/eastern Washington
Temperature 50-80 degrees Fahrenheit

I picked this bike up a couple weeks back and just can’t seem to get it tuned right. I’m experiencing what I think is a rich bog through each gear. There is also a pretty bad stutter/hesitation around mid-3/4 of the gears rpms. Mostly noticeable in first and second gear when slowly progressing through the gear around 1/8-1/4 throttle. When I fly through the gears full throttle the bike will power right through the sputter/hesitation but still feels a bit low/boggy. There is no popping coming from the exhaust on decel.
My brother has a 2007 wr250f with an fmf slip on and I used his main jet(162) and jet needle (four notches down I believe) and this didn’t seem to really help at all.
I’ve tried to read through some forums regarding these issues with this bike and it seems like a lot of people have unplugged their tps to get rid of the problem. When I unplug mine it definitely helps quite a bit but idle is still a bit rough and power isn’t as crisp as I would like. Definitely off from my brothers WR. I would like to be able to leave the tps plugged in and not just put a band aid over the problem. First plug I pulled after buying the bike was very black. I swapped that out when I got the bike and recently pulled the new plug and that was starting to turn a dry black as well.

For the pilot circuit it will fire right up without any choke and the reason the fuel screw is turned all the way in is because when I try to turn it out at all the idle gets worse. My understanding is when this happens I need to drop a pilot size but 38 already seems pretty lean.

Went through recently and cleaned the carb which was a massive pain in the ass on this model and my buddy mentioned that the float height was off and had adjusted that a bit. He didn’t measure the adjustment simply eyeballed it. So I’m thinking that probably wouldn’t be a bad place to start for the idle circuit but the bog/hesitation was there before the carb cleaning.

Any insights/pointers as to what to try next? Running out of ideas here.



What was the conclusion to this post? Did you end up solving the issue? 

The Shop

christiande
Posts
3
Joined
5/27/2021
Location
Spokane, WA US
11/19/2023 12:37pm
2009 wr250f with a rekluse z start auto and an fmf slip on 38 pilot jet Aftermarket fuel screw 0 turns out Jet needle on leanest...
2009 wr250f with a rekluse z start auto and an fmf slip on

38 pilot jet
Aftermarket fuel screw 0 turns out
Jet needle on leanest setting at highest notch
170 main jet
Altitude 1800-4500 feet north Idaho/eastern Washington
Temperature 50-80 degrees Fahrenheit

I picked this bike up a couple weeks back and just can’t seem to get it tuned right. I’m experiencing what I think is a rich bog through each gear. There is also a pretty bad stutter/hesitation around mid-3/4 of the gears rpms. Mostly noticeable in first and second gear when slowly progressing through the gear around 1/8-1/4 throttle. When I fly through the gears full throttle the bike will power right through the sputter/hesitation but still feels a bit low/boggy. There is no popping coming from the exhaust on decel.
My brother has a 2007 wr250f with an fmf slip on and I used his main jet(162) and jet needle (four notches down I believe) and this didn’t seem to really help at all.
I’ve tried to read through some forums regarding these issues with this bike and it seems like a lot of people have unplugged their tps to get rid of the problem. When I unplug mine it definitely helps quite a bit but idle is still a bit rough and power isn’t as crisp as I would like. Definitely off from my brothers WR. I would like to be able to leave the tps plugged in and not just put a band aid over the problem. First plug I pulled after buying the bike was very black. I swapped that out when I got the bike and recently pulled the new plug and that was starting to turn a dry black as well.

For the pilot circuit it will fire right up without any choke and the reason the fuel screw is turned all the way in is because when I try to turn it out at all the idle gets worse. My understanding is when this happens I need to drop a pilot size but 38 already seems pretty lean.

Went through recently and cleaned the carb which was a massive pain in the ass on this model and my buddy mentioned that the float height was off and had adjusted that a bit. He didn’t measure the adjustment simply eyeballed it. So I’m thinking that probably wouldn’t be a bad place to start for the idle circuit but the bog/hesitation was there before the carb cleaning.

Any insights/pointers as to what to try next? Running out of ideas here.



lhansen14 wrote:

What was the conclusion to this post? Did you end up solving the issue? 

It was the air cut valve. Someone put it back in the wrong order so it was basically just stuck open with the spring and diaphragm backwardsIMG 7409

Post a reply to: Jetting issues? Tps? WR250F

The Latest