Opaque oil sight glass

[Dave20046]

that dizzyblonde's oil side extremely dark I thought it was just stained.


Tazdaz you should top up your oil to between those lines when cold. Althoguh I'm wondering where the oils been hiding if it goes past f when warm...surely it can't expand that much. Have you dried running the bike for 20 seconds from cold then switching off and checking?

Checking oil:

Hold the bike upright, see where the oil level rests. If you cant see it, or its below the line, then put some oil in. Running with low oil level will increase the risk of engine damage occuring, and will also stop the engine from cooling as efficiently.

[yorkie_chris]

Increase the risk? No matt, low oil is a cast iron guarantee of a total engine failure. Not "if" .... "when".

If it is run low, then the massive extra heat will more than likely lead to a hot siezure. If you're lucky you may get away with a rebore, but probably not.
Or if it goes the other way, then the big end bearings will sieze to the crank until the shells spin, the crank will be scored, the bearing shells reduced to dust which will not do the rest of the motor much good either. One f##ked crank, zero chance of economical repair.

Originally Posted by yorkie_chris

Increase the risk? No matt, low oil is a cast iron guarantee of a total engine failure. Not "if" .... "when".

If it is run low, then the massive extra heat will more than likely lead to a hot siezure. If you're lucky you may get away with a rebore, but probably not.
Or if it goes the other way, then the big end bearings will sieze to the crank until the shells spin, the crank will be scored, the bearing shells reduced to dust which will not do the rest of the motor much good either. One f##ked crank, zero chance of economical repair.

The above would be why I have a 2nd engine waiting to be fitted to the CG125 in my back garden.

(sheered it's sump plug whilst I was riding it at 70mph - abracadabra, oil on the back tyre which is now locked solid whilst I'm in effectively motorway traffic at rush hour )

Originally Posted by yorkie_chris

Increase the risk? No matt, low oil is a cast iron guarantee of a total engine failure. Not "if" .... "when".

If it is run low, then the massive extra heat will more than likely lead to a hot siezure. If you're lucky you may get away with a rebore, but probably not.
Or if it goes the other way, then the big end bearings will sieze to the crank until the shells spin, the crank will be scored, the bearing shells reduced to dust which will not do the rest of the motor much good either. One f##ked crank, zero chance of economical repair.

Were doomed. Doomed I tells yah!.

All true though.

[Dave20046]

I love YC's heart warming optimism

[yorkie_chris]

We're doomed.

YC, it depends on how low the oil is; granted, having only a litre left is pretty much like saying "go on engine, die a death now". But if its just below the sight glass (like this chap appears to be noticing) he maaaaay be getting away with it. The risk of engine/mechanical faliure rises (i suppose exponentially) with lessening oil - but its not like its iminent seizure if the oil is just below the sight-glass.

You can't half feel it though when the oil is getting low. I can, my gear shifts are not as smooth and the engine is louder

[yorkie_chris]

Bottom of the sightglass is about 1.5 litres IIRC. Low enough to cause overheating problems.

I have 2 blown curvy motors here, I have some pics of the state of the big-end bearings shells somewhere if you would like to see them? They both had oil levels that were a little bit below the sightglass.

Yes he "mayyyy" be getting away with it for now, but open the throttle up a bit and it's just a matter of time before it goes bang in an expensive way.

So, FFS, make sure your motor has oil in it...

Originally Posted by yorkie_chris

I have some pics of the state of the big-end bearings shells somewhere if you would like to see them?

go for it