Posts: 169
Joined: 6/4/2017
Location: Pinson, AL USA
I'm not sure if this is normal or not but I have a Honda cr125 that I'm working on and when I took the pipe off there was black oil that came out the pipe and exhaust flange. Not a lot but I'd say maybe a cup or half a cup? I had only ran it for a total of 20 minutes after the rebuild. I didn't see any oil shooting out the back when it was running. I run a 32:1 oil ratio.
Posts: 1090
Joined: 10/28/2015
Location: Grand Terrace, CA USA
Posts: 115
Joined: 11/22/2017
Location: Fort Dodge, IA USA
Definitely not normal. 32:1 is a good mixture so it's not that. What ratio was ran before you rebuilt it? Is it possible the oil was in there before the rebuild?
Posts: 169
Joined: 6/4/2017
Location: Pinson, AL USA
Posts: 169
Joined: 6/4/2017
Location: Pinson, AL USA
Edited Date/Time:
No because I got this bike in a box in pieces and put it all together with lots of new parts. The pipe was cleaned and the cylinder was cleaned and honed and the exhaust flange is brand new.
Posts: 456
Joined: 12/17/2009
Location: WV, USA
In a 2 stroke motor that we deal with, there is only 2 ways to get excessive oil in an exhaust pipe. Well maybe 3...
1. Unburnt oil in fuel mix. Usually rich jetting.
2. Tranny oil getting sucked into the crankshaft area through the seals. New seals needed.
3. For the third one, tranny oil seeping through the center case sealing surfaces. Did you use the correct sealer? (Yamabond) Or is the sealing surfaces nicked up or not flat? (needs lapped)
These are the only 3 ways that you will find oil in the pipe, short of dumping a cup of oil in there...
A big thanks goes out to Donnie at Morgantown Powersports and RJ at Beaver Creek Cycles
