Oil out of the exhaust?

alright so im almost done going over the bike now (06 rm125) and inoticed that when the bike runs i have oil that leaks from where the cylinder and the expansion chamber(exhaust) meet and im no 2 stroke pro but im pretty sure that aint normal, anyone have any ideas as to whats goin on? And no i didnt put any oil where oil doesnt go.
 

SRAD97750

Moderator
Staff member
Perfectly normal for a 2 stroke to spooge at the exhaust. There may be an o-ring as well, but that will only mask the rich condition.
It is a sign of an overall rich condition, usually minimized by properly setting the float per the manual.
-BIG DAN:thumb:
 
I'll fitting pipe, o-ring if it has it, too rich, pipe already coated inside and when it gets hot it liquefies and runs downhill. Did you repack the silencer and clean the spark arrestor if it has one?
 
I'll fitting pipe, o-ring if it has it, too rich, pipe already coated inside and when it gets hot it liquefies and runs downhill. Did you repack the silencer and clean the spark arrestor if it has one?
And what exactly does rich mean? Fuel to air? Or is it the gas and oil mixture thats too rich?
 
total fuel amount too rich=jetting too rich. This can be the float level as above, pilot, needle, or main. Its trial and error. I would see what jets are in it and set the float. Then look into what others have changed their jetting to in order to fix the stock settings from the factory.
 
Do you have a manual for this bike?
Usually the dirtiest black nasty oil soaked part you will remove from a 2T when breaking it down! Being a 2T the pipe will have been off a fair few times so if If any of the bolts are wrong and too long you won't have a seal and it will leak oil there! New o-ring if reqd and check the bolts are correct and nipped tight!
All your microfiche here-
http://www.partzilla.com/parts/search/Suzuki/Motorcycle/2006/RM125/parts.html

Perfectly normal for a 2 stroke to spooge at the exhaust. There may be an o-ring as well, but that will only mask the rich condition.
It is a sign of an overall rich condition, usually minimized by properly setting the float per the manual.
-BIG DAN:thumb:
 
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And what exactly does rich mean? Fuel to air? Or is it the gas and oil mixture thats too rich?
Oil/gas is a ratio, when we say rich or lean we are always talking fuel/air, and the terms always refer to the fuel. The fuel contains oil, but is still fuel. Rich = too much fuel, lean = not enough fuel.
A certain percentage of the oil in the fuel mix goes through the system unburned, and collects in the pipe, silencer packing and the inflamed nostrils of the Sierra club set.
 
So i checked the float yesterday and it was all good so i guess ill try to just clean out the exhaust and put it back on making sure it seals well. And does anyone know the stock jet sizes for this bike?
 
So i checked the float yesterday and it was all good so i guess ill try to just clean out the exhaust and put it back on making sure it seals well. And does anyone know the stock jet sizes for this bike?


Replace the silencer packing as well.
Procircuit.com will have it on their jetting page. You can also follow their jetting charts but then again if the motor isn't fresh everything you do will be for not.
 
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