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Davidpm12

YZ125 Yz 125 oil coming out of exhaust

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Yz125 2 stroke oil coming out of exhaust, I know some comes out but it tends to drip out. Can that mean over fueled or? I made sure to mix fuel properly to what it calls for

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1 hour ago, Davidpm12 said:

Yz125 2 stroke oil coming out of exhaust, I know some comes out but it tends to drip out. Can that mean over fueled or? I made sure to mix fuel properly to what it calls for

I'd like to give you a short answer but there is a bit to this question...

It's not a bad thing unless there is LOTS of it. If there's just a little on the exhaust tip than your just a little rich or you are not riding the bike hard enough. 

With same jetting (My 2011 yz125) , if I go trail riding at a medium speed, there will be a little oil out of the exhaust.. I will also foul plugs too. If I go on a motocross track, riding hard, No fouled plugs and a completely dry silencer. This is why you need to change your jetting between how you ride. 

As long as you aren't fouling plugs and there isn't oil gushing out the silencer i'd say its fine. 2 strokes are very sensitive in jetting and you always want to jet your carb for weather, and riding style. 

Try riding the bike harder. It is a 2 stroke 125 after all... You could also change the needle position. Try 1 position higher. (Leaner). 

What year is your bike? How do you ride it?  Does the bike bog at all? The stock yz125 needles are terrible. I got a jd jet kit and the needles are much better for throttle response and running.

WHATEVER YOU DO, DO NOT RUN LESS OIL IN YOUR MIX. THIS WILL NOT LEAN OUT THE BIKE.     I use 32:1 ALWAYS

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3 hours ago, Aaron C. said:

I'd like to give you a short answer but there is a bit to this question...

It's not a bad thing unless there is LOTS of it. If there's just a little on the exhaust tip than your just a little rich or you are not riding the bike hard enough. 

With same jetting (My 2011 yz125) , if I go trail riding at a medium speed, there will be a little oil out of the exhaust.. I will also foul plugs too. If I go on a motocross track, riding hard, No fouled plugs and a completely dry silencer. This is why you need to change your jetting between how you ride. 

As long as you aren't fouling plugs and there isn't oil gushing out the silencer i'd say its fine. 2 strokes are very sensitive in jetting and you always want to jet your carb for weather, and riding style. 

Try riding the bike harder. It is a 2 stroke 125 after all... You could also change the needle position. Try 1 position higher. (Leaner). 

What year is your bike? How do you ride it?  Does the bike bog at all? The stock yz125 needles are terrible. I got a jd jet kit and the needles are much better for throttle response and running.

WHATEVER YOU DO, DO NOT RUN LESS OIL IN YOUR MIX. THIS WILL NOT LEAN OUT THE BIKE.     I use 32:1 ALWAYS

Aaron really caught most of the serious points in his response above. 
How old is the bike? what year?

How hard is it ridden?

Do you know when the silencer was repacked last??

Could be nothing at all, or possibly just need to adjust riding style or jetting. If you want to verify the Jets in it and clip position, let us know what year it is and your conditions (altitude and temperatures), someone on here will be glad to help you figure it out. Just don’t assume there’s anything actually wrong... could be normal based on conditions.... With 2 strokes spooge happens, you just need a little more info to determine if it’s excessive. 

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3 hours ago, Aaron C. said:

I'd like to give you a short answer but there is a bit to this question...

It's not a bad thing unless there is LOTS of it. If there's just a little on the exhaust tip than your just a little rich or you are not riding the bike hard enough. 

With same jetting (My 2011 yz125) , if I go trail riding at a medium speed, there will be a little oil out of the exhaust.. I will also foul plugs too. If I go on a motocross track, riding hard, No fouled plugs and a completely dry silencer. This is why you need to change your jetting between how you ride. 

As long as you aren't fouling plugs and there isn't oil gushing out the silencer i'd say its fine. 2 strokes are very sensitive in jetting and you always want to jet your carb for weather, and riding style. 

Try riding the bike harder. It is a 2 stroke 125 after all... You could also change the needle position. Try 1 position higher. (Leaner). 

What year is your bike? How do you ride it?  Does the bike bog at all? The stock yz125 needles are terrible. I got a jd jet kit and the needles are much better for throttle response and running.

WHATEVER YOU DO, DO NOT RUN LESS OIL IN YOUR MIX. THIS WILL NOT LEAN OUT THE BIKE.     I use 32:1 ALWAYS

Bike does bog alittle. Bike is currently at the leanest the needle can get(highest positions) it’s a 2002 Yamaha yz 2 stroke. Bike does bog in first if I floor it all the way in first, actually it sounds like it’s coughing ok it’s self. Like it chokes for a quick second then goes. But only in that gear. And I also noticed that it does not really like to cruise at slow speeds in first gear. But I know it’s 2 stroke so they are made to run hard so that could be normal I’m not sure. 

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13 minutes ago, 502Racing said:

Aaron really caught most of the serious points in his response above. 
How old is the bike? what year?

How hard is it ridden?

Do you know when the silencer was repacked last??

Could be nothing at all, or possibly just need to adjust riding style or jetting. If you want to verify the Jets in it and clip position, let us know what year it is and your conditions (altitude and temperatures), someone on here will be glad to help you figure it out. Just don’t assume there’s anything actually wrong... could be normal based on conditions.... With 2 strokes spooge happens, you just need a little more info to determine if it’s excessive. 

It’s a 2002 Yamaha yz 2 stroke. I’m not sure when the silencer was repacked. I actually just got the bike. And did basic work cleaned filter, put new spark plug, change oil and flushed coolant. Cleaned the carbs and checked the hight of the float and inspected internals. 

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1 minute ago, Davidpm12 said:

Bike does bog alittle. Bike is currently at the leanest the needle can get(highest positions) it’s a 2002 Yamaha yz 2 stroke. Bike does bog in first if I floor it all the way in first, actually it sounds like it’s coughing ok it’s self. Like it chokes for a quick second then goes. But only in that gear. And I also noticed that it does not really like to cruise at slow speeds in first gear. But I know it’s 2 stroke so they are made to run hard so that could be normal I’m not sure. 

If its idling on the stand, and you whack full throttle does it fall on its face? this is lean. Seems like your just not riding hard enough. If it completely dies when it bogs that lean. Try richening the needle and air screw and keep that 125 pinned. As you learn to ride harder the spooge will go away.

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Just now, Davidpm12 said:

It’s a 2002 Yamaha yz 2 stroke. I’m not sure when the silencer was repacked. I actually just got the bike. And did basic work cleaned filter, put new spark plug, change oil and flushed coolant. Cleaned the carbs and checked the hight of the float and inspected internals. 

Who doesn’t love a new to you bike! Awesome.

If you didn’t have the Jets out pull the cap screw on the bottom and pull them/check your jet sizes , main (6mm hex) and pilot (small flat blade). 
According to FMF’s chart, an 02 with exhaust should use a 410 main, 30 pilot, and the Needle clip should be in the middle or 3rd position. That’s for sea level and 72 degrees temperature. 
What’s  your altitude and how’s your outdoor temperature right now? Then just adjust a bit to get where you should be... I live in northern Utah near 5000’ and have to go a step or 2 leaner on all my bikes.

I would also repack that silencer immediately, It’s possibly 18+years old,  packing is cheap, kind of easy, and then you’re at a baseline to make proper jetting changes. Bikes lose power quick with a plugged silencer. Nobody seems to think about it though...

Enjoy the bike. Really one of the best overall useable rides out there... my sons will do anything and go anywhere even with huge guys riding it, they always get off the bike with a grin....

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David-

I question the leanest clip position?  Even at 5k’ I’m at mid or 2nd clip... if you’re not at 7500’ then someone was probably chasing an issue. (Or had NOCLUE) How’s the compression feel? I’ve seen guys lean bikes way out trying to stop plug fouling. Unfortunately the plugs were fouling due to an easily replaced crank seal.... I’ve got a couple bikes cheap cause of that... 

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32 minutes ago, 502Racing said:

Who doesn’t love a new to you bike! Awesome.

If you didn’t have the Jets out pull the cap screw on the bottom and pull them/check your jet sizes , main (6mm hex) and pilot (small flat blade). 
According to FMF’s chart, an 02 with exhaust should use a 410 main, 30 pilot, and the Needle clip should be in the middle or 3rd position. That’s for sea level and 72 degrees temperature. 
What’s  your altitude and how’s your outdoor temperature right now? Then just adjust a bit to get where you should be... I live in northern Utah near 5000’ and have to go a step or 2 leaner on all my bikes.

I would also repack that silencer immediately, It’s possibly 18+years old,  packing is cheap, kind of easy, and then you’re at a baseline to make proper jetting changes. Bikes lose power quick with a plugged silencer. Nobody seems to think about it though...

Enjoy the bike. Really one of the best overall useable rides out there... my sons will do anything and go anywhere even with huge guys riding it, they always get off the bike with a grin....

Ok I will check that, the temp here about 77 I’m not sure about the attitude. That’s what I thought I prolly should put it on the middle ( recommendation) and go from there. That’s just how I got the bike and it was already set at its leanest setting 

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17 minutes ago, Davidpm12 said:

Ok I will check that, the temp here about 77 I’m not sure about the attitude. That’s what I thought I prolly should put it on the middle ( recommendation) and go from there. That’s just how I got the bike and it was already set at its leanest setting 

Where do you live?

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2 hours ago, Davidpm12 said:

Houston texas

You’re a sea level, lucky...

set it up as stock 410mj 30pj and put the clip in the middle and good luck!!!

so how she does and go from there

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2 minutes ago, 502Racing said:

You’re a sea level, lucky...

set it up as stock 410mj 30pj and put the clip in the middle and good luck!!!

so how she does and go from there

Haha, I too have the luxury of living and riding near seal level

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6 minutes ago, 502Racing said:

You’re a sea level, lucky...

set it up as stock 410mj 30pj and put the clip in the middle and good luck!!!

so how she does and go from there

10/4 will do. Appreciate all the help 

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