Article: "The Oil Truth"

[David in Sugar Land]

My Norton-riding friend in Crete, Gerry Bristol wrote an article for Real Classic (a UK bike magazine) a few years ago. He has a lifetime of work in the motor oil industry and contributes regularly to the Brit-Iron mailing list and other classic motorcycle online groups. He always offers sound advice for those of us just barely able to keep their machines running, but learning more all the time.

There is some history and some good, basic info in this short article.

http://www.realclassic.co.uk/techfiles/oil030319.html

 

[fuel tanker man]

Decent piece.

I do take exception with his contention: "Synthetic oils have a number of advantages over the old dead dinosaur juice and, used correctly, virtually eliminate wear caused by friction."

I used to think that way as well, but the evidence is piling up so quickly to the contrary that it's hard for a thinking person to go there any more; dino oils are, in many cases, turning in better UOA's than syns these days, and would appear to be protecting just as well in most cases--even when the dinos are pushed to extended OCI's.

It's not good to run an oil the necessary three times the usual OCI in order to justify the cost of a synthetic. Too much can happen to contaminate or weaken the oil in a carburated, air cooled motorcycle engine. Much better to change the oil out sooner, not later.

Flash points on some of the newer dinos are as good or better than those on many synthetics.

From all I've seen and read, the dino oils changed at frequent (2500 miles or so) OCI's have set the standard for low metal wear and long engine life--at least in the air cooled Harley Davidsons.

Dan

 

[TR3-2001SE]

I don't know your age fuel tanker man but my guess is not very old. If you have seen many engines run on dino and 3000 mile changes after any high milage figure you care to come up with, you would feel differently. I have owned these cars. Several to past 250,000. Then do tear downs on high milage cars run on synthetic oil with reasonable changes 6000-10,000. You will see the reason for synthetic oil. As one oil author said it is like comparing light bulbs to lazers. I see why no one who cares about their auto long term using dino anymore. Just my 2 cents.

 

[fuel tanker man]

There are two Harley Davidson Evolution powered bikes in the museum in Milwaukee. These bikes were serviced at 2500 mile intervals with HD 360 dino oil.

One bike, belonging to Dave Willet of High Point, NC went around 410,000 miles. I spoke to one of the mechanics at Curly's Harley Davidson in Winston Salem and he said that he was present when mechanics from Tilley's (Statesville, NC) tore that engine down at 240,000 miles "just out of curiosity." The only noteable wear was to one of the cam lobes, and though it wasn't critical they did replace the cam at that mileage. Harley Davidson had told Willet to continue the same maintenance program and document it and they wanted to "talk to him" when the bike reached 400K. When it did, they traded him a new bike for his '87 Tour Glide in 2002. Willet has over 200K on that bike at last report.

Another rider from the Pacific Northwest put over 460,000 miles on a similar bike. Can't remember the year model, but he ran a side car. He too had no major engine problems from his machine, and he too ran the 2500 mile OCI's on HD 360 dino oil.

There was a feature in American Iron magazine a couple years back on the two bikes mentioned above.

While 400+ K miles isn't the norm, 100K miles can be reached easily enough with the Harley Big Twins.

I know of two HD's in my area which have reached the 100K mark, both on 20W50 dino oil.

Dan

 

[Jay]

quote:

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Originally posted by fuel tanker man:
Decent piece.

I do take exception with his contention: "Synthetic oils have a number of advantages over the old dead dinosaur juice and, used correctly, virtually eliminate wear caused by friction."

I used to think that way as well, but the evidence is piling up so quickly to the contrary that it's hard for a thinking person to go there any more; dino oils are, in many cases, turning in better UOA's than syns these days, and would appear to be protecting just as well in most cases--even when the dinos are pushed to extended OCI's.

---

As a long time proponent of synthetic oils, especially Mobil1, I'm forced to agree. Dino oils are consistently delivering lower wear numbers in my UOA reports than synthetics--even the expensive "boutique" synthetics. I think I would be using Havoline dino in my car even if it sold at a premium to Mobil1--that it sells for 1/3 the price makes it an incredible bargain!

Synthetics still have their place in very cold environments. They may leave fewer deposits than dino oils, but I think that's much less the case with the newer hydrocracked dinos.

 

[Cujet]

Do not forget the better thermal stability of synthetics, both hot and cold. Turbo use is another reason for synthetics.

Chris

 

[LVHospiceRN]

quote:

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Originally posted by Cujet:
Do not forget the better thermal stability of synthetics, both hot and cold. Turbo use is another reason for synthetics.

Chris

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and the ELVES, dont forget the ELVES....they are another perfectly great reason to use German Castrol, i mean, synthetic!!!

darrell
sin city

 

[Jaybird]

When we consider racing bikes, we see temps much higher than what a normal sunday rider may see.
For that reason alone I feel that synthetic provides and advantage over dino.

Frequency of change is the single most important issue with MC oils, but when we see oil temps topping 375-400f, the top shelf synthetics will not degrade as a dino oil will.

 

[SlowDave]

Jaybird,
Not necessarily. My racebike coolant doesn't go over 100C/212F unless something is wrong (e.g. blown headgasket) or they stick us on the grid while some hack tries to get his stalled bike out of the way (rare). This is a lightweight bike (400cc 4 cyl) so I can't say this applies to all race bikes, but it does to mine. Since the oil is cooled by the coolant, its temperature is greatly affected by the coolant temp. Admittedly, it is also affected by the work put into it through the bearings and piston cooling nozzles (if so equipped), etc.

On my streetbike on the other hand, stuck in traffic in El Paso (who knew you were allowed to SHUT DOWN I-10?), I pegged the coolant temp gage on my streetbike (oil also cooled by the coolant) so... There are no numbers on the coolant temp gage, but from my experience, I would expect that red zone to be at least 250F, more likely 260F. I get way up in that temperature gage anytime I get stuck in gridlock on my streetbike, so it is much more typical there, IMHO.

 

[SlowDave]

quote:

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Originally posted by Jaybird:

Frequency of change is the single most important issue with MC oils, but when we see oil temps topping 375-400f, the top shelf synthetics will not degrade as a dino oil will.

---

I agree Jaybird. My question is, does anyone have access to any operating oil temperature data showing temps above 300F? I remember an article way back when talking about ?Honda? and that they fitted oil coolers as a factory item (e.g. Nighthawk 700/S) to any bike that showed oil pan temps above...?280F? in operation. My thoughts are that synthetic would be absolutely key in the kind of temps that you mention, but that no motorcycles anywhere get to those kind of temps, but I really don't know.

Anyone got data, or a magazine article, or something?

 

[Jaybird]

Racing motocross bikes and off-road air-cooled bikes can often see high oil temps.

The most notorious for high temps are the high revving mini's.

The clutch makes lots of heat. And you will see the temp of the oil much higher than the temp of your coolant in the radiator.