Honda CX 500 Forum banner
1 - 16 of 16 Posts

·
Registered
Joined
·
322 Posts
Discussion Starter · #1 ·
I did an oil replacement on my 1980 CX500 yesterday. I change the oil every 1000 km and the oil filter every second oil change.

The oil that came out of the engine was still in "good" condition. I filled up with high quality 20W50 mineral oil out of a new container. I was topping up and took the dipstick out when I saw a bright white stripe (about 4 mm wide) across the upper part of the dipstick - looked like paint... I could see another white streak floating in the oil inside the motor. I wiped the dipstick and the white came off clean.

The old oil I took out was not water contaminated at all. There is no coolant leak from the mec. seal on the outside. The oil inside the new container that remained was 100%....

What did I see??
 

·
Super Moderator
Joined
·
23,094 Posts
Sounds like emulsified oil.

A small amount doesn't necessarily indicate a fault.

This can occur from repeated short trips or use in cold or humid weather.

But check that the weep hole is clear.
 

·
Registered
Joined
·
2,071 Posts
Paper/foil from the refill bottle??
I once found grass in the coolant expansion tank of a Bmw of a bike dealer serviced many years ago
 

·
Registered
Joined
·
2,457 Posts
Oil change every 1000 km? If you were closer I’d take your used oil and put it in my equipment 😁
 

·
Registered
Joined
·
322 Posts
Discussion Starter · #5 ·
Oil change every 1000 km? If you were closer I’d take your used oil and put it in my equipment 😁
Yes - religiously... I rode that 1000 km in one year... the bike is old - taking no deliberate chances...
 
  • Like
Reactions: bahn88

·
Registered
Joined
·
322 Posts
Discussion Starter · #6 ·
Sounds like emulsified oil.

A small amount doesn't necessarily indicate a fault.

This can occur from repeated short trips or use in cold or humid weather.

But check that the weep hole is clear.
Seems the most probable explanation. Thanks!
 

·
Registered
Joined
·
2,071 Posts
Yes - religiously... I rode that 1000 km in one year... the bike is old - taking no deliberate chances...
Yeah....when i got my 750 the previous owner put 500km on in 1 year.....so out went that oil and filter.....
 

·
Super Moderator
'84 CX650E that is evolving into a GL500
Joined
·
17,275 Posts
Did you warm the engine up fully before you drained the oil?
If not, did you warm the engine up fully the last time you ran it before you changed the oil?

A small amount of unburned gasses can get past the rings until the engine warms up enough to close the gaps in the piston rings and any moisture in that air can condense and mix with the upper surface of the oil in the crankcase. If the engine is run until fully warmed up that moisture usually boils off and exits via the crankcase breather.

If you have any doubts warm up the engine and look at the dipstick again.
 

·
Registered
81 Gl500i 83 CX650E
Joined
·
1,899 Posts
Back 40 years ago we apprentices were taught to change oil every 3000 miles/5000kms or every three months. Engines produce water when burning gas which gets into the oil. Short trips are the worst thing for any vehicle ,as they don't get hot enough to boil the water out of the oil. So th OP is correct in changing his oil every 1000kms which sounds like once a year . Hopefully his rides are longer than it takes for the engine to warm fully up.
 
  • Like
Reactions: Wyn64

·
Registered
Joined
·
1,387 Posts
I rode that 1000 km in one year
Gotcha. I change the oil every year regardless if the mileage is under the recommended interval. Like someone said, oil is degraded by other things than mileage.
 
  • Like
Reactions: Wyn64

·
Registered
Joined
·
322 Posts
Discussion Starter · #11 ·
Did you warm the engine up fully before you drained the oil?
If not, did you warm the engine up fully the last time you ran it before you changed the oil?

A small amount of unburned gasses can get past the rings until the engine warms up enough to close the gaps in the piston rings and any moisture in that air can condense and mix with the upper surface of the oil in the crankcase. If the engine is run until fully warmed up that moisture usually boils off and exits via the crankcase breather.

If you have any doubts warm up the engine and look at the dipstick again.
I rode it for 20 km before draining the oil. I will have to inspect the weep hole... is that possible from the outside with everything intact?
 

·
Super Moderator
'84 CX650E that is evolving into a GL500
Joined
·
17,275 Posts
Yes. The pics on the page linked below show it with everything removed for clarity but if you know where it is you can get a wire into it without taking anything apart.
 

·
Super Moderator
Joined
·
5,155 Posts
  • Like
Reactions: bahn88 and Wyn64

·
Registered
Joined
·
2,071 Posts
If done in-situ would the general recommendation be to go below 2.5mm probe (eg 0.5-1mm bread board wire) or would the smaller gauge just bend.....
 

·
Super Moderator
Joined
·
5,155 Posts
1 - 16 of 16 Posts
Top