missing oil???

one of the 3 150s i woork on has sudenly began to loose 200cc of oil every time out. the oil is not comng out anywhere and dose not look like it is coming out of the pipe. I will not be abble to do a teardown until later this week. any ideas on where to start. I suspect rings or valve seals, as no oil transfer to clutch is ocuring.

my guess is the rings hope you fix it any other problems with motor.

we had the same with a 07 rb the piston rings had turned 50ml of oil every 15min race.

well i still have not had time to teardown, pulled motor and replaced with another from a parts bike for this weekend. pulled the sparkplug and it is still ash white almost looks like im running a little lean, not at all like oil is going through engine. thanks for any help i'll keep yall posted when i teardown.

There are min possable

1: Check the sparkplug if is clean then you can rule out the rings and intake valve stem ware and bad valve seals.

Note if you look very carely for Ash Fouled which is a buildup of combustion deposits stems primarily from the burning of oil and/or fuel addatives during normal combustion., it can "mask" the spark result as looking like normal condition and only way see this heavier deposits are allowed to accumulate over long periods with out change the sparkplug.

2: Check the exhaust valve by pulling the exhaust pipe if don't see any oil caked or wet look a round the valve stem then need move on.

3: It maybe be a seal leak on the clutch side which seal the crank case oil from the transmission oil side.

4: Check all your vent tube.

cam cover vent tube was slightly pinched replaced and all is well. thx for all the help.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now