Engine Oil

[JasonB]

Just wondering what type and weight oil are people using for a 250 Ducati.

JasonB

[JimF]

I use straight 40 weight VR1 racing oil from Valvoline.

Jim

[kmev]

I'm planning to run straight 40 weight non-detergent oil.

It's my understanding that since this engine doesn't have a modern oil filter and just a simple oil screen a non-detergent oil is more appropriate, as non-detergent allows contaminants to fall out of suspension (which is appropriate due to lack of a filter) while detergent oils keep contaminants in suspension so they can be filtered out.

Please correct me if I am wrong. My engine hasn't run since 1972, but with luck it will this weekend!

[JasonB]

I am using a Silkolene 15w-50w at the moment, I was thinking of a straight weight oil, I was thinking Castrol.

Regards
JasonB

[DewCatTea-Bob]

____ For normal 'riding-weather', straight-40 was always the right-way to go (since it flows easily enough during such desired seasonal temperatures).
But when good ('SE' rated) 50w & 20w50 became available, I then always used 1qt of 20w50 & 1qt of 50w, and topped-up with 40w,, all Valvoline Racing-oil. ...
__ If ya study-up on oil-tech, 15w50 ought to be best for either when cold or fully heated-up, but I just don't trust that pure multi-weight will maintain the important qualities of the 40w & 50w, (of which mainly is to better absorb & carry-off otherwise destructive heat, away-from the bearings).
__ I agree that a non-detergent type oil is fine enough, so long as it's most-always dumped-out while still hot, right-after each extended use of the motor,, otherwise all internal horizontal surface-areas will become coated with carbon-soot build-up !


Dukaddy-DUKEs,
DCT-Bob

[ericpritchard]

Years ago, Henry Hogben told me to use Kendall 40.
I've been using it exclusively ever since, on the track, and have a pretty good reliability record.
Regards
Eric Pritchard

[Bevel bob]

I use any classic 40 , which I am told hangs around on surfaces better than 20/50, probably better also to cope with worn bush in timing cover , I do take it gently 3-4 k revs till warm as 40 is a bit slow to drain from the head. Avoid synth and car oils designed for those with catalitic converters.

[MotoMike]

I haven't been reading up on the topic lately, but a couple decades ago there was a fair amount of writing on the topic of oil for 4 stroke motorcycles with the wet clutch and gearbox sharing the same oil. -
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There are those who hold the opinion that the oil used there should be motorcycle specific for the following reasons:
The oil used in a car engine will not experience the shearing effect it would get from passing continuously through a transmission gear train. In the transmission the gears will grind up the special long chain molecules that are added to give the oil it’s multi viscosity qualities. The oil stock used for to create multi-viscosity oil is that represented by the lower number. So, if the multi viscosity property of a 20-50 were defeated, you’d be left with a 20 weight oil. In reality, the multi-viscosity properties are slowly compromised by the shearing effect and probably still remains in range far beyond a normal change interval.
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Oil designed for car engines have additives that are designed to coat surfaces with a slickening quality. This quality is not desired in a wet clutch and may degrade your clutch and cause premature failure.
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These old air cooled engines will run hotter than water cooled car engines and will be harder on the oil.
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I believe the big companies have addative packages that are designed to address the special conditions that exist in a motorcycle engine.
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I can’t see using a non-detergent oil now-a-days. When I first started wrenching it was not uncommon to see amazing quantities of sludge and gunk built up in an engine when you tore it down. At that time there were horror stories of detergent oils ruining engines and many refused to use them. The oils of 35 years ago are stone aged compared to the oils we have today. 15 years ago I worked occasionally with a buddy who had an engine shop and I was struck with just how clean the insides of the engines we tore down were. And these were engines being rebuilt. The old tech oil allowed the debris and combustion byproducts to settle out and become gunk. The new oils suspend them in the oil until they are drained.
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At the change interval I use, I’m not worried about oil failure. If you use the Ducati recommended interval I believe you will be very safe as these recommendations were made when oils really sucked. Many years ago I had a couple Jap bikes, I did a somewhat unscientific test by placing a drop of dirty about to be changed oil next to a drop of clean fresh oil on a piece of shiny card stock. I then turn the card surface vertical. Even after hard highway miles and some dessert highways in California, the drops always fell at about the same rate. Since the oil was at ambient temp at the time of the test, I would probably have been checking only the base stock viscosity.
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For the reasons stated above, I use oil designed for 4 stroke motorcycle engines in my Ducati 450. I am at present using Valvoline 20-50 four stroke motorcycle oil, but would use any that I believed had a real research and development department. The Valvoline oil label makes mention of wet clutch protection.
My two cents. Oil discussions can get as deep as electronic discussions.

[JasonB]

Hi, and thanks everyone who has replyed. As Motomike has said it could be just as a in depth conversation as electrics, but in big font (hehe).
Funny how different parts of the world reccomend diffrent brand oils, downunder where I live (Australia) we have a brand Called Nulon which is a great automotive oil, but alas they are not into motorbike oil. I have a mate who swears by Morris oils and another who reckons Castril XXL 40 is the bee knees. I think there is too much to consider when it comes to oil properties.

JasonB

[kmev]

Ok, so I changed my mind on non-detergent and just bought some Kendall 40.