YZ250 Lean pilot issue

scraprecon
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scraprecon 12/3/2018 11:51am
12/3/2018 11:51am
With ignition cover removed, I put propane in stator area and noticed no difference in idle. You would think if it's leaking and running lean, it would pull the propane in and cause it to either shut off or rev up
mattyhamz2
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mattyhamz2 12/3/2018 12:10pm
12/3/2018 12:10pm
scraprecon wrote:
With ignition cover removed, I put propane in stator area and noticed no difference in idle. You would think if it's leaking and running lean, it...
With ignition cover removed, I put propane in stator area and noticed no difference in idle. You would think if it's leaking and running lean, it would pull the propane in and cause it to either shut off or rev up
But what about the right side crank seal? I saw that suggested more than once.
scraprecon
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scraprecon 12/3/2018 12:19pm
12/3/2018 12:19pm
scraprecon wrote:
With ignition cover removed, I put propane in stator area and noticed no difference in idle. You would think if it's leaking and running lean, it...
With ignition cover removed, I put propane in stator area and noticed no difference in idle. You would think if it's leaking and running lean, it would pull the propane in and cause it to either shut off or rev up
mattyhamz2 wrote:
But what about the right side crank seal? I saw that suggested more than once.
I put propane into the trans vent hose, no change. Also put soapy water in hose with 6 psi, no bubbling at all. Saw a vid of a banshee with a leaking ride side crank seal, water/bubbles came shooting out when he airleak tested it. Nothing with mine. I thought that was a pretty sound test
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mattyhamz2 12/3/2018 12:36pm
12/3/2018 12:36pm
scraprecon wrote:
With ignition cover removed, I put propane in stator area and noticed no difference in idle. You would think if it's leaking and running lean, it...
With ignition cover removed, I put propane in stator area and noticed no difference in idle. You would think if it's leaking and running lean, it would pull the propane in and cause it to either shut off or rev up
mattyhamz2 wrote:
But what about the right side crank seal? I saw that suggested more than once.
scraprecon wrote:
I put propane into the trans vent hose, no change. Also put soapy water in hose with 6 psi, no bubbling at all. Saw a vid...
I put propane into the trans vent hose, no change. Also put soapy water in hose with 6 psi, no bubbling at all. Saw a vid of a banshee with a leaking ride side crank seal, water/bubbles came shooting out when he airleak tested it. Nothing with mine. I thought that was a pretty sound test
What pipe and silencer combo are you running?

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scraprecon
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scraprecon 12/3/2018 12:40pm
12/3/2018 12:40pm
mattyhamz2 wrote:
But what about the right side crank seal? I saw that suggested more than once.
scraprecon wrote:
I put propane into the trans vent hose, no change. Also put soapy water in hose with 6 psi, no bubbling at all. Saw a vid...
I put propane into the trans vent hose, no change. Also put soapy water in hose with 6 psi, no bubbling at all. Saw a vid of a banshee with a leaking ride side crank seal, water/bubbles came shooting out when he airleak tested it. Nothing with mine. I thought that was a pretty sound test
mattyhamz2 wrote:
What pipe and silencer combo are you running?
Pro circuit pipe with a freshly repacked factory muffler. Had this problem with an fmf turbine muffler also.
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mattyhamz2 12/3/2018 12:47pm
12/3/2018 12:47pm
scraprecon wrote:
I put propane into the trans vent hose, no change. Also put soapy water in hose with 6 psi, no bubbling at all. Saw a vid...
I put propane into the trans vent hose, no change. Also put soapy water in hose with 6 psi, no bubbling at all. Saw a vid of a banshee with a leaking ride side crank seal, water/bubbles came shooting out when he airleak tested it. Nothing with mine. I thought that was a pretty sound test
mattyhamz2 wrote:
What pipe and silencer combo are you running?
scraprecon wrote:
Pro circuit pipe with a freshly repacked factory muffler. Had this problem with an fmf turbine muffler also.
Ya man, I hate how they run with the stupid S/A's on. I was curious to see what PC and FMF recommended for jetting vs what you have.
scraprecon
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scraprecon 12/3/2018 1:46pm
12/3/2018 1:46pm
mattyhamz2 wrote:
What pipe and silencer combo are you running?
scraprecon wrote:
Pro circuit pipe with a freshly repacked factory muffler. Had this problem with an fmf turbine muffler also.
mattyhamz2 wrote:
Ya man, I hate how they run with the stupid S/A's on. I was curious to see what PC and FMF recommended for jetting vs what...
Ya man, I hate how they run with the stupid S/A's on. I was curious to see what PC and FMF recommended for jetting vs what you have.
SA? What's that?
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mattyhamz2 12/3/2018 1:48pm
12/3/2018 1:48pm
scraprecon wrote:
Pro circuit pipe with a freshly repacked factory muffler. Had this problem with an fmf turbine muffler also.
mattyhamz2 wrote:
Ya man, I hate how they run with the stupid S/A's on. I was curious to see what PC and FMF recommended for jetting vs what...
Ya man, I hate how they run with the stupid S/A's on. I was curious to see what PC and FMF recommended for jetting vs what you have.
scraprecon wrote:
SA? What's that?
Spark arrestor
scraprecon
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scraprecon 12/3/2018 1:49pm
12/3/2018 1:49pm Edited Date/Time 12/3/2018 1:51pm
mattyhamz2 wrote:
Ya man, I hate how they run with the stupid S/A's on. I was curious to see what PC and FMF recommended for jetting vs what...
Ya man, I hate how they run with the stupid S/A's on. I was curious to see what PC and FMF recommended for jetting vs what you have.
scraprecon wrote:
SA? What's that?
mattyhamz2 wrote:
Spark arrestor
Lol, makes sense. Thing was spooge city with that muffler, dripping all over swingarm. Not a drip with this factory muffler. Fmf settings for my bike are:
178 main
50 pilot
Stock needle 3rd clip
1.5 AS

My settings currently:
172 main
55 pilot
Stock needle 3rd clip
3 1/2 AS
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mattyhamz2 12/3/2018 1:58pm
12/3/2018 1:58pm
scraprecon wrote:
SA? What's that?
mattyhamz2 wrote:
Spark arrestor
scraprecon wrote:
Lol, makes sense. Thing was spooge city with that muffler, dripping all over swingarm. Not a drip with this factory muffler. Fmf settings for my bike...
Lol, makes sense. Thing was spooge city with that muffler, dripping all over swingarm. Not a drip with this factory muffler. Fmf settings for my bike are:
178 main
50 pilot
Stock needle 3rd clip
1.5 AS

My settings currently:
172 main
55 pilot
Stock needle 3rd clip
3 1/2 AS
I checked PC as well and PC jetting rec is
175 main
50 pilot
Stock Needle in 2nd clip
1.5 AS
RyanLester761
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RyanLester761 12/3/2018 2:09pm
12/3/2018 2:09pm
Here is an old video I took of the neighbor kid revving my cr125 with a bad right side seal. It got worse as it revved. The seal was popped out of the case big time! Check it out.

You said your bike revs clean, so I'd imagine your seal is good? Just weird because your exhaust looks "steamy" like mine did. And mine spooged oil out of the muffler too.

(I left a comment on your YouTube also.)

And for the record, I turn my idles way down on my 2-strokes. I don't like my bikes to chug-a-lug when entering corners.

Following this thread. Interested to learn, myself.

https://www.youtube.com/watch?v=dgAFKKY88nk
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scraprecon
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scraprecon 12/3/2018 3:54pm
12/3/2018 3:54pm
RyanLester761 wrote:
Here is an old video I took of the neighbor kid revving my cr125 with a bad right side seal. It got worse as it revved...
Here is an old video I took of the neighbor kid revving my cr125 with a bad right side seal. It got worse as it revved. The seal was popped out of the case big time! Check it out.

You said your bike revs clean, so I'd imagine your seal is good? Just weird because your exhaust looks "steamy" like mine did. And mine spooged oil out of the muffler too.

(I left a comment on your YouTube also.)

And for the record, I turn my idles way down on my 2-strokes. I don't like my bikes to chug-a-lug when entering corners.

Following this thread. Interested to learn, myself.

https://www.youtube.com/watch?v=dgAFKKY88nk
Thanks for commenting! That is crazy! Mine smokes a little but clears out once I ride it. Taking it out tonight to an open area to ride and tune it a bit more. We are going to get to the bottom of this
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mattyhamz2
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mattyhamz2 12/3/2018 3:59pm
12/3/2018 3:59pm
RyanLester761 wrote:
Here is an old video I took of the neighbor kid revving my cr125 with a bad right side seal. It got worse as it revved...
Here is an old video I took of the neighbor kid revving my cr125 with a bad right side seal. It got worse as it revved. The seal was popped out of the case big time! Check it out.

You said your bike revs clean, so I'd imagine your seal is good? Just weird because your exhaust looks "steamy" like mine did. And mine spooged oil out of the muffler too.

(I left a comment on your YouTube also.)

And for the record, I turn my idles way down on my 2-strokes. I don't like my bikes to chug-a-lug when entering corners.

Following this thread. Interested to learn, myself.

https://www.youtube.com/watch?v=dgAFKKY88nk
scraprecon wrote:
Thanks for commenting! That is crazy! Mine smokes a little but clears out once I ride it. Taking it out tonight to an open area to...
Thanks for commenting! That is crazy! Mine smokes a little but clears out once I ride it. Taking it out tonight to an open area to ride and tune it a bit more. We are going to get to the bottom of this
I take it you live out west haha
scraprecon
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scraprecon 12/3/2018 9:48pm
12/3/2018 9:48pm
RyanLester761 wrote:
Here is an old video I took of the neighbor kid revving my cr125 with a bad right side seal. It got worse as it revved...
Here is an old video I took of the neighbor kid revving my cr125 with a bad right side seal. It got worse as it revved. The seal was popped out of the case big time! Check it out.

You said your bike revs clean, so I'd imagine your seal is good? Just weird because your exhaust looks "steamy" like mine did. And mine spooged oil out of the muffler too.

(I left a comment on your YouTube also.)

And for the record, I turn my idles way down on my 2-strokes. I don't like my bikes to chug-a-lug when entering corners.

Following this thread. Interested to learn, myself.

https://www.youtube.com/watch?v=dgAFKKY88nk
scraprecon wrote:
Thanks for commenting! That is crazy! Mine smokes a little but clears out once I ride it. Taking it out tonight to an open area to...
Thanks for commenting! That is crazy! Mine smokes a little but clears out once I ride it. Taking it out tonight to an open area to ride and tune it a bit more. We are going to get to the bottom of this
mattyhamz2 wrote:
I take it you live out west haha
I'm in South Carolina, weather was nice tonight. Unfortunately, didn't get to mess with the 250. Was having too much fun on my 125!
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yz133rider
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yz133rider 12/4/2018 5:11am
12/4/2018 5:11am
Did you think to check the right side crank seal?
scraprecon
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scraprecon 12/4/2018 7:15am
12/4/2018 7:15am
yz133rider wrote:
Did you think to check the right side crank seal?
I put propane(unlit) into the trans vent hose and saw no change in idle. Will try putting into trans fill hole to see if it makes a difference.
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yz133rider 12/4/2018 7:52am
12/4/2018 7:52am
yz133rider wrote:
Did you think to check the right side crank seal?
scraprecon wrote:
I put propane(unlit) into the trans vent hose and saw no change in idle. Will try putting into trans fill hole to see if it makes...
I put propane(unlit) into the trans vent hose and saw no change in idle. Will try putting into trans fill hole to see if it makes a difference.
I was being funny since its been suggested 30 times.

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kb228
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kb228 12/4/2018 9:56am
12/4/2018 9:56am
Really dude its easy to do crank seals. I dont know why you dont just to rule it out.

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yz133rider
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yz133rider 12/4/2018 10:33am
12/4/2018 10:33am
Id say leaks are finicky. They cam come and go based on pressures, heat, expanding and contracting so dont rule anything out.
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kb228 12/4/2018 10:39am
12/4/2018 10:39am
kb228 wrote:
Really dude its easy to do crank seals. I dont know why you dont just to rule it out.
scraprecon wrote:
Educate yourself.
https://www.duncanracing.com/TechCenter/2stk_presstest.pdf
Ok bro ill make it damn simple for you. You have a hanging idle. Your carb is messed up, you have an air leak in your motor, or your jetting/float height is wrong.

Youre convinced all of those things are perfectly fine and you want US to tell you some magical other thing wrong with your bike, over the internet, where we cant physically examine it. Good luck fixing it.
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paddyB745 12/4/2018 10:46am
12/4/2018 10:46am
Have you tried looking for air leaks by spraying carb cleaner around the carb and intake or LH crank seal while it’s running?
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scraprecon
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scraprecon 12/4/2018 11:17am
12/4/2018 11:17am
paddyB745 wrote:
Have you tried looking for air leaks by spraying carb cleaner around the carb and intake or LH crank seal while it’s running?
I used unlit propane, I've heard that's the best and safest way to find air/vacuum leaks on cars and bikes. Put propane everywhere around the engine, intake area, cylinder and head, engine cases(and underneath), and around stator area with cover removed, no difference. Put near air filter and bike died right away, so I know the propane was working. May throw in some crank seals and see what happens, even though it passed the test which doesn't make sense.
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scraprecon 12/4/2018 2:52pm
12/4/2018 2:52pm
Update!
Decided to replace ignition side crank seal, it did look a little crooked. Replaced it, through it back together with 55 pilot, no difference. Still sounds lean and is surging.
scraprecon
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scraprecon 12/4/2018 2:54pm
12/4/2018 2:54pm Edited Date/Time 12/4/2018 2:55pm
Old seal
New seal

And I did clean inside stator area before installing cover btw
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mattyhamz2
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mattyhamz2 12/4/2018 3:04pm
12/4/2018 3:04pm Edited Date/Time 12/4/2018 3:05pm
scraprecon wrote:
Old seal [img]https://p.vitalmx.com/photos/forums/2018/12/04/307461/s1200_IMG_0757.jpg[/img] New seal [img]https://p.vitalmx.com/photos/forums/2018/12/04/307467/s1200_IMG_0768.jpg[/img] And I did clean inside stator area before installing cover btw
Old seal
New seal

And I did clean inside stator area before installing cover btw
What about the right side?

Edit: What's with all the debris in there??
scraprecon
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scraprecon 12/4/2018 3:19pm
12/4/2018 3:19pm
scraprecon wrote:
Old seal [img]https://p.vitalmx.com/photos/forums/2018/12/04/307461/s1200_IMG_0757.jpg[/img] New seal [img]https://p.vitalmx.com/photos/forums/2018/12/04/307467/s1200_IMG_0768.jpg[/img] And I did clean inside stator area before installing cover btw
Old seal
New seal

And I did clean inside stator area before installing cover btw
mattyhamz2 wrote:
What about the right side?

Edit: What's with all the debris in there??
Right crank seal next. I wish I knew about the debris, got this bike a month ago so couldn't really tell you.
mattyhamz2
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mattyhamz2 12/4/2018 3:24pm
12/4/2018 3:24pm
scraprecon wrote:
Old seal [img]https://p.vitalmx.com/photos/forums/2018/12/04/307461/s1200_IMG_0757.jpg[/img] New seal [img]https://p.vitalmx.com/photos/forums/2018/12/04/307467/s1200_IMG_0768.jpg[/img] And I did clean inside stator area before installing cover btw
Old seal
New seal

And I did clean inside stator area before installing cover btw
mattyhamz2 wrote:
What about the right side?

Edit: What's with all the debris in there??
scraprecon wrote:
Right crank seal next. I wish I knew about the debris, got this bike a month ago so couldn't really tell you.
I assume you cleaned it originally and this is from after your rebuild?
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scraprecon 12/4/2018 3:27pm
12/4/2018 3:27pm Edited Date/Time 12/4/2018 3:28pm
mattyhamz2 wrote:
What about the right side?

Edit: What's with all the debris in there??
scraprecon wrote:
Right crank seal next. I wish I knew about the debris, got this bike a month ago so couldn't really tell you.
mattyhamz2 wrote:
I assume you cleaned it originally and this is from after your rebuild?
Never rebuilt the engine. This was the first time having the flywheel off, previous owner must've cleaned the debris out. Crank had zero play, felt perfect.
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mattyhamz2 12/4/2018 3:33pm
12/4/2018 3:33pm Edited Date/Time 12/4/2018 3:33pm
scraprecon wrote:
Right crank seal next. I wish I knew about the debris, got this bike a month ago so couldn't really tell you.
mattyhamz2 wrote:
I assume you cleaned it originally and this is from after your rebuild?
scraprecon wrote:
Never rebuilt the engine. This was the first time having the flywheel off, previous owner must've cleaned the debris out. Crank had zero play, felt perfect.
My bad, I thought you rebuilt it. Must have mixed it up with another post. That's pretty bad though. I bought mine back in April and rebuilt it completely. Mine didn't look anything like that inside when I pulled the cover off and the motor had never been apart before. That debris is kinda sketchy.

I could be wrong, but it looks like there's pitting at the bottom of the case like something broke off and went bouncing around in there at some point.

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