I thought that air-cooled engines are supposed to roast their oil?

[richard612]

Lab: Schaeffer's Specialized Lubricants

Engine: 739cc air/oil-cooled four-stroke four-cylinder motorcycle engine with combined transmission and wet clutch.

Miles on engine: 17389

Miles on oil sample: 2900

Miles on oil filter: 2900

Oil: Mobil Delvac 1300 Super 15W-40 (current API CI-4/SL formulation).

Make-up oil added: Approx 5% of total crankcase volume.

Operating conditions: 45F to 100F, mixed high and low speed/RPM, no short trips, moderate idle time.

Engine condition/tune: Good overall. Mild knock at startup. Factory jetting, pilot screws 3 turns out (overrich idle). Stock exhaust, airbox, and air filter element.

Copper: 2ppm
Iron: 16ppm
Chromium: 0ppm
Aluminum: 6ppm
Lead: 1ppm
Molybdenum: 71ppm
Phosphorus: 1769ppm
Zinc: 1852ppm
Magnesium: 757ppm
Calcium: 4071ppm

Anti-freeze: 0% (duh!)
Fuel Dilution: None noted
H2O: 0%
Silicon: 3ppm
Viscosity: 13.67cSt @ 100C (SAE 40W)
(Mfr viscosity spec: 15.5cSt @ 100C)

Oxidation: 9%
Nitration: 2%
TBN: Not tested.
Soot: Not tested.

 

[Chris]

What kind of bike, a Nighthawk maybe? Not a real high performance engine so may not be as punishing. Iron seems a bit high. Does anyone know if the high level of calcium, in this diesel oil, can cause any problems in this application? If the bike had a Cat. could it cause a problem?

 

[Pops]

richard612

Over the previous oil used whatever it might have been did you notice a gas milaege drop using this oil ?

 

[msparks]

quote:

---

Originally posted by Chris:
Does anyone know if the high level of calcium, in this diesel oil, can cause any problems in this application? If the bike had a Cat. could it cause a problem?

---

My BMW has a Cat and I have been using Amsoil which also has a great deal of CA in it. No problems with my Cat.

From what I understand Ph is what is supposed to kill cats, that why the SL forumulation has reduced Zn and Ph. Though Amsoil as well as have higher amounts of ZDDP with no problems.

I feel if you use a higher quality oil, you will get less blow-by, therefore reducing the amount of poisoning to the cats! But who am I anyway

 

[satterfi]

The viscosity loss would suggest that the oil did suffer quite a bit, especially for only 2900 miles.

 

[richard612]

quote:

---

Originally posted by satterfi:
The viscosity loss would suggest that the oil did suffer quite a bit, especially for only 2900 miles.

---

Just how serious is this loss? Would you drain when it falls out of grade or sometime before then?

 

[satterfi]

quote:

---

Originally posted by richard612:

quote:

---

Originally posted by satterfi:
The viscosity loss would suggest that the oil did suffer quite a bit, especially for only 2900 miles.

---

Just how serious is this loss? Would you drain when it falls out of grade or sometime before then?

---

I don't have a clue. Next time send your oil to Terry, then you can ask a pro. You'll also get a TBN value.

Edit: Ok, that is a smart *** answer but you would really be better off asking someone like Terry than just anyone on the internet, like me.

BTW, motorcycles do grind up the oil a lot and viscocity loss is a parameter that needs to be watched, more than car applications. I think it's the transmission. But if you're smart, you'll ask a pro.

[ December 13, 2002, 09:37 PM: Message edited by: satterfi ]

 

[richard612]

quote:

---

Originally posted by Chris:
What kind of bike, a Nighthawk maybe?

---

ZR-7. Very similar engine. Late 70's era, 10k redline, 65-68 rear wheel HP.

No catalyst.

 

[Bror Jace]

I haven't seen as many used bike samples as I would like ... but that sample doesn't look too bad. But the iron should ideally be lower ... especially after only 2,900 miles.

Perhaps the moly in this oil has now plated up on those gears and an identical run would yield lower wear numbers?

I think the iron comes from the gears in the gearbox ... and I agree with scatterfi that they are what really tears up motors oils in bikes. I would not run this oil past 3,000 miles in this bike.

After seeing Terry's analysis on some other examples, he generally thinks that oils should stay in grade throughout the drain interval. It was thought that Castrol's 5W30 shears down to a 5W20 in about a thousand miles so the oil will give better fuel economy. I think this is bogus. If the owner wants to use 5W20, it's now widely available and he could buy that grade to start with.

--- Bror Jace

 

[dragboat]

Welll here is three less cylinders to compare the Fe with but Fe will come from the gears as well.Al can come from the clutch backing plates " factory" The anaylsis below reminds me why I never liked the Mobil Trysyn

http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=000061

 

[Bror Jace]

Yeb, Dreamboat, I rescind my earlier comments about the iron in this example. They really don't look bad at all in light of some more recent samples.

--- Bror Jace