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Have I bought a heap of...

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DaveB:
... junk, ... problems, ...any other word

On returning from a 20 mile ride I saw the following... Please watch one or both videos...





I'm pretty sure this is condensation, not smoke, and the white liquid is either emulsified oil or condensation with a little oil from the breather. Is this normal? To be expected? or have I bought a whole heap of trouble? I'm just surprised it there could still be so much condensation in the engine after 20 miles.

I thought when checking the oil level the other day I saw a little emulsified oil on the dipstick but then ruled it out immediately because it's not liquid cooled. Never thought about condensation and I don't remember my CB 550 K3 ever doing this back in 1980.

Sorry, I know I'm asking a lot of questions but I'm sizing up what I've bought.

Thanks.

Bryanj:
Buy some fresh oil and a filter then take it out for another  decent ride them change oil immediately you get home, probably get better with regular us. 550 has oil in engine case so oil stays warmer

mike the bike:
Water could have sneaked past the dipstick O ring.  If there's water in with the oil,  then you're going to get steam coming out of the breather.  As Brian says...fresh oil, and a fresh O ring.

philward:
I would change to oil and flush through as per previous posts. Might just be that the bike has been standing and condensation formed due to hot and cold changes in temp. There is certainly no mechanical cause but the issue is to get any water vapor out before it does any damage

K2-K6:
As the others have posted, I don't think it's too bad. If it's been run much recently on choke and not brought up to full temperature then it will have an excess of water vapour in the oil. I'd not expect it to stop steaming given those circumstances until something like 50 to 100 miles of running. In 20 miles it just hasn't had enough time at decent heat to evaporate much.

Try doing this, smell the oil on the dipstick and compare it to new oil. I'll have a bet that it reeks of petrol. If so, Bryan's advice to change it is even more relevant.

As a comparison to more modern engines, the choke system on these is really crude and amounts to not much more than stuffing a rag into the intake. There is no corresponding throttle lifting connected to the choke operation and it literally just stops the air going into the motor. It runs very rich to start it and you're best to get it off choke ASAP which requires you to moderate engine warm up with the throttle. It really is that manual.

You get alot of unburnt fuel in that situation and quite a bit of it will pass the rings and just mix with the oil. That's how water gets into oil on any of these old aircooled engines.

The 550 K3 was also a lean burn setup I believe, so far less likely to do this. Although looking similar, they are fundamentally better (nobody likes those carbs though) for running and engine without excess fuel being used and not entirely combusted.

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