petrol in oil?

[JZS 600]

I think HG 10/40 semi IS Motul!


(just cheaper,,,)

[darrsi]

[color=rgb(34, 34, 34)][size=1em]Mixing Mineral and Synthetic oils [/size][/color][color=rgb(80, 80, 80)]"...Here's the current thinking on the subject of mixing mineral and synthetic oils. This information is based on the answer to a technical question posed on the Shell Oil website:
There is no scientific data to support the idea that mixing mineral and synthetic oils will damage your engine. When switching from a mineral oil to a synthetic, or vice versa, you will potentially leave a small amount of residual oil in the engine. That's perfectly okay because synthetic oil and mineral-based motor oil are, for the most part, compatible with each other. (The exception is pure synthetics. Polyglycols don't mix with normal mineral oils.)
There is also no problem with switching back and forth between synthetic and mineral based oils. In fact, people who are "in the know" and who operate engines in areas where temperature fluctuations can be especially extreme, switch from mineral oil to synthetic oil for the colder months. They then switch back to mineral oil during the warmer months.
There was a time, years ago, when switching between synthetic oils and  mineral oils was not recommended if you had used one product or the other for a long period of time. People experienced problems with seals leaking and high oil consumption but changes in additive chemistry and seal material have taken care of those issues. And that's an important caveat. New seal technology is great, but if you're still driving around in a car from the 80's with its original seals, then this argument becomes a bit of a moot point - your seals are still going to be subject to the old leakage problems no matter what newfangled additives the oil companies are putting in their products..."[/color]

[unfazed]

[quote author=unfazed link=topic=8389.msg82761#msg82761 date=1371744868]
[quote author=darrsi link=topic=8389.msg82658#msg82658 date=1371686870]
10w/40 is 10w/40 

Not true :rolleyes
The are 3 basic types of 10/40 oil
Mineral 10/40
Semi Synthetic 10/40
Synthetic 10/40
Neither should be mixed with each other, whereas you may top up semi synthetic with fully synthetic and fully synthetic with semi synthetic, under no circumstances should mineral oil be mixed with fully synthetic of semi synthetic.
As I said the specification should match before you decide to mix
[/quote]

10w/40 is 10w/40, sure, there is mineral based oil and synthetic ester based oil, but there's no ill symptoms of mixing them, and you'll find that even most "Semi-Synthetic" and "Fully Synthetic" oils are already diluted with upto 20% standard mineral oil anyway!

There was an article by the Chief of R&D at Silkolene/Fuchs a few years ago which highlighted exactly this.
[/quote]
May have been the case a few years ago, but Castrol say differently now with the newer spec high performance oils. They do not say you can't they say you should not. It is not the recommended thing to do.
A bit like driving the wrong way up a one way street, you can, but you should not :lol

[marksfazer]

I had this problem with petrol in oil a little while ago with a mates Triumph. We stripped the carb's replaced the needle seats/valves and made sure the floats were moving freely.
The problem never happened again.


On old carb'ed bikes the petrol tap use to cause this problem as well, but as the fazer has electric pump can't see it being that.


Mark

[robby boy]

When you changed the oil how did it look/smell, was it really thin and runny, did it smell petrolly, my guess is you have a bit of condensation in the crankcase due to short runs with the bike not getting a chance to get hot, I would keep an eye on the oil level, as if it is leaking fuel into the sump your oil level would go up. (personal view only, this information my not be true :lol )


I personally would not mix mineral and synthetic oils, as I remember when Ford brought out there first zetec engines we had a few in with sticky valves in the valve stems which Ford claimed was caused by a chemical reaction between the 2 different oils.

[keno]

When you changed the oil how did it look/smell, was it really thin and runny, did it smell petrolly, my guess is you have a bit of condensation in the crankcase due to short runs with the bike not getting a chance to get hot, I would keep an eye on the oil level, as if it is leaking fuel into the sump your oil level would go up.

Drained oil smells of petrol
Dirty brown colour looked normal consistency for used oil
Oil level has never gone up or down.

[igor5b]

Hey Keno

I was wondering if you sorted the problem out and found the cause of the emulsion?

[keno]

No, just going to put it down to condensation as since the warmer weather is coming seems to be a lot better,had to clean inside of clutch housing twice as it was really bad and changed the oil and stripped out all crankcase breather tubes they where badly gunged up,come to think of it i think the same happened last winter as well.

[Slaninar]

Motul says it can be mixed. 




Mix it - no problems. BTW Motul's semi-synth 5100 oil is a bit less good than the other producers' similar oils  - while it costs a bit more.