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Discussion Starter #1 (Edited)
use 20W-50 oil ONLY!

Hello Ladies & Gents, I just wanted to let the Forum members here know that they should use a 20W-50 motor oil only, even though the manual says you can use a 10W-40 motor oil, as some of you know, my 102HP "MOTOR OF DEATH" died, I lost my crankcase ball bearings, and the rod bearings looked like they had 100,000 miles on them! :eek: after a close examination, by some mechanics & crankshaft specialists, it may have come down to the incorrect weight oil, I have used the 10W-40 oil since new, & I now have about 12,000 mi.

After talking to some race shops here & in Europe, I found that they ALL use the 20W-50 oil, for some reason the air-cooled Ducatis are especially hard on the oil & needs the heavier oils to help absorb the "pounding" the bottom end takes. The top-end was in great shape, so go figure.

I have ALWAYS used top quality motorcycle specific synthetic motor oils & change it every 2500mi. this time it did not make the difference.:cool:

So this is what I learned...........
1. If you do track-days use 20-50
2. if you just ride hard use 20-50
3. if its over 80 degrees use 20-50
4. if you have more HP than stock use 20-50
5. if your bike is stock, and you ride like a Grandma, and its a winter snow storm you can get away with a 10-40 :D

So this in NOT a I use this oil brand or that oil brand, I don't care what oil you use, just use a good 20W-50 motorcycle oil, change it often, and hopefully you don't go through what I'm going through, lesson over. :p Aloha Alex
 

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surely it depends on where you live and the temperatures you expect to hit. I was already recommended 20-50 i think by my shop.
 

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Huh.

How about 15w-50? (full synthetic)

I don't even know the the numbers mean :eek: ...turns to google
 

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And they didn't tell you that and fill it with 20-50 when they built it why??? Alex, I'm not buying it. The first thing I thought when I heard your motor cooked was, they fucked up.Didn't you have a problem with the valves when you first got it back too? I don't think the oil was the cause of your failure. I'm pretty sure there are guys out there with a lot more HP running 10-40.Best of luck with round two.Please understand I'm not trying to be a dick with this post, you seem like a hell of a nice guy.:)
 

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The W stands for winter!! not weight!! a 15 or 20w50 is basically a 50 weight oil with the 15 or 20 or?? added in which will circulate better at lower temps... If you live in a very hot climate you could just run straight 50 weight... I could go on!!
 

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I always use 50W in my rigs, especially when your hammering on them. I am using 10W - 50 in the Hyper. It's the second number that counts most, the first number is a cold start number.

Here is an explanation, I have seen better ones.

This is either a single number (e.g., 30 weight) or a pair of numbers separated by the letter W (e.g., 10W30.) The latter type is much more commonly used these days, and are the only type that most automobile manufacturers specify in operators manuals. The first number in the designation (10W) is the apparent viscosity of the oil when it is cold; the W stands for `winter'. The second number (30) is the viscosity of the oil when hot. There is a trick here; the oil doesn't actually get thicker (turn from 10 weight to 30 weight) as it gets hotter. What is actually happening is that when the oil is cold, it has the viscosity of a cold 10 weight oil. as it gets hotter, it doesn't get thin as fast as a 10W oil would; by the time it is up to temperature, it has the viscosity of a hot 30 weight oil.

Note that these numbers actually specify ranges of viscosities; not all 10W oils have exactly the same viscosity when cold, and not all 30 weight oils have the same viscosity when hot. Also the behavior of multi-grade oils is caused by additives, and it has been reported that some 10W40 oils do not retain their multi-grade characteristics well over time. But 10W30, 15W40, and 20W50 oils work fine.

Out!
 

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Discussion Starter #9
And they didn't tell you that and fill it with 20-50 when they built it why??? Alex, I'm not buying it. The first thing I thought when I heard your motor cooked was, they fucked up.Didn't you have a problem with the valves when you first got it back too? I don't think the oil was the cause of your failure. I'm pretty sure there are guys out there with a lot more HP running 10-40.Best of luck with round two.Please understand I'm not trying to be a dick with this post, you seem like a hell of a nice guy.:)
No the shop did not fuckup, the bottom end has never been opened till now.
On my valve issue ,it was the aftermarket valve collets that proved too tight,
that gave a false bottomed out feeling, until it actually seated.

I know that there are a lot of guys out there that are running the 10w40 motor oil, heck, I'm one of them! I always believed that a good quality lighter weight oil would make more power & still protect the motor, but in this case I was wrong, and all the race shops that I have spoken with that know this motor say to use the 20w50 motor oil, and I AM a hell of a nice guy, :rolleyes: thanks Aloha Alex
 

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No the shop did not fuckup, the bottom end has never been opened till now.
On my valve issue ,it was the aftermarket valve collets that proved too tight,
that gave a false bottomed out feeling, until it actually seated.

I know that there are a lot of guys out there that are running the 10w40 motor oil, heck, I'm one of them! I always believed that a good quality lighter weight oil would make more power & still protect the motor, but in this case I was wrong, and all the race shops that I have spoken with that know this motor say to use the 20w50 motor oil, and I AM a hell of a nice guy, :rolleyes: thanks Aloha Alex
That's good to hear.By the way, I've always been a fan of heavier oils especially on an air cooled motor. It never ceases to amaze me how thin hot engine oil is when draining it. Like frickin water.Maybe I'll heed your warning.:eek:
 

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Discussion Starter #12
20/50 is for Hawgs :D

10 or 15 /50
Most definitely /50 for air cooled machines

I like Silkolene 10/50 for winter
15/50 summer

Good luck Alex the MotorKillah
My bike IS a Hawg, a MONEY HAWG!! :cool: Aloha Alex:sleep:
 

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With a multi-viscosity oil (like 20W-50), the first number is the viscosity at 0 degrees C,
and the second is the equivalent viscosity at 100 degrees C.

Quote:
"Multi-viscosity oils have polymers added to a light base (5W, 10W, 20W), which
prevent the oil from thinning as much as it warms up. At cold temperatures the
polymers are coiled up and allow the oil to flow as their low numbers indicate.
As the oil warms up, the polymers begin to unwind into long chains that
prevent the oil from thinning as much as it normally would. The result is that at
100 degrees C, the oil has thinned only as much as the higher viscosity number
indicates. Another way of looking at multi-vis oils is to think of a 20W-50 as a
20 weight oil that will not thin more than a 50 weight would when hot."

While it is better to use a 20W-50 in highly stressed engines (esp. air-cooled
engines), I would bet there were other contributing factors to the death of the
"Motor of Death"-- especially since a good synthetic oil was being used. The
film strength of the oil only goes so far to protect the bearing surfaces. Unless
you've been running oil temps consistently higher than 260 F or so, the oil
itself was probably not the most critical factor in the crank bearing failure,
although oil delivery to the bearings might have been an issue.

If the rod bearings "look like they had 100,000 miles on them", I've seen
where connecting rod misalignment causes this type of damage. Once the
rod bearing wears badly, it can take out the main bearing and vice versa.

Misalignment can be caused by a distorted bearing bore, bent connecting rod,
or combustion problems causing uneven side-loading on the piston and
connecting rod. "Hammering" loads caused by detonation due to too much ignition
advance, or excessive compression for the fuel used would lead to this type
of damage. Lugging the engine when in too high of a gear can also contribute
to bearing fatigue.

How high was the compression ratio on this motor? Any ignition timing changes
or a raised rev limit? I would be very careful about re-assembling this
engine in the same configuration and parts as before without really
knowing what killed it. If it really is a friction failure, the difference between
40 and 50 weight oil is probably not enough margin to definitely prevent future
problems, it will just take a little longer, IMO.
 

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I suppose that's why BMW suggests 20w-50 for their air cooled, OIL-DRINKING, hexheads. Hec, they go as far as promoting non-synthetic oil for the first 6k miles!

Grandma's are nice people too (not Alex...me). :eek:
 

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I use 20w50, in my forks.
























(kidding)
 

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I am a 10w40 guy as well, and I will remain one. There are a bunch of great "oil" articles online, and every one that I have read that tests oil with air cooled motors show many different weights with near identical low wear levels, regardless of viscosity. This doesn't mean that different weights wouldn't be better for different circumstances of course, but for your average motorcycle rider in your average climate, I think 10w40 is as good as it gets. :)
 

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22,000 miles right here. 10-40 since new. I bought my Hyper in October of 2007 - 5 or 6 track days, 40 mile regular commute, regular rides to Laguna(from San Diego), and I beat the shit out of it. No issues at all. I am not about to switch oil wieght. My 900SS used the same oil, and so did my 916. Come to think of it, so did my RC51, my NT650 race bike, my 450SMR, my 625SMC, my DRz400SM, my T509, my TL1000, my Superhawk, my CRF250, my XR600, my XR400, my RZ350, my RD400, my FZ600, my GPz550....
 

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With a multi-viscosity oil (like 20W-50), the first number is the viscosity at 0 degrees C,
and the second is the equivalent viscosity at 100 degrees C.

Quote:
"Multi-viscosity oils have polymers added to a light base (5W, 10W, 20W), which
prevent the oil from thinning as much as it warms up. At cold temperatures the
polymers are coiled up and allow the oil to flow as their low numbers indicate.
As the oil warms up, the polymers begin to unwind into long chains that
prevent the oil from thinning as much as it normally would. The result is that at
100 degrees C, the oil has thinned only as much as the higher viscosity number
indicates. Another way of looking at multi-vis oils is to think of a 20W-50 as a
20 weight oil that will not thin more than a 50 weight would when hot."

While it is better to use a 20W-50 in highly stressed engines (esp. air-cooled
engines), I would bet there were other contributing factors to the death of the
"Motor of Death"-- especially since a good synthetic oil was being used. The
film strength of the oil only goes so far to protect the bearing surfaces. Unless
you've been running oil temps consistently higher than 260 F or so, the oil
itself was probably not the most critical factor in the crank bearing failure,
although oil delivery to the bearings might have been an issue.

If the rod bearings "look like they had 100,000 miles on them", I've seen
where connecting rod misalignment causes this type of damage. Once the
rod bearing wears badly, it can take out the main bearing and vice versa.

Misalignment can be caused by a distorted bearing bore, bent connecting rod,
or combustion problems causing uneven side-loading on the piston and
connecting rod. "Hammering" loads caused by detonation due to too much ignition
advance, or excessive compression for the fuel used would lead to this type
of damage. Lugging the engine when in too high of a gear can also contribute
to bearing fatigue.

How high was the compression ratio on this motor? Any ignition timing changes
or a raised rev limit? I would be very careful about re-assembling this
engine in the same configuration and parts as before without really
knowing what killed it. If it really is a friction failure, the difference between
40 and 50 weight oil is probably not enough margin to definitely prevent future
problems, it will just take a little longer, IMO.
This is an oil thread, which we all know, are the pits, so I don't want to fan the issue of what oil to use more than desired, however, it was my understanding that the best protection is offered by mulitgrade oils with the widest range between numbers, ie a 5 w 50 will protect your engine better than say a 10 w 40 or a 20 w 50, as it has better flow when cold as a 5 grade, and we all know cold start ups are when most wear/damage occurs, and will then act like a 50 grade at higher temps, ie visocity, not "weight" will increase due to changes at the molecular level. I agree that lugging the engine will damage the bottom end so it's best to keep the spinning/on the boil. As fas as air cooled engines needing different oil, I'm not sure why that would be the case. If you want to run "heavier" oil, it won't flow as well, though may burn off less, so you add a little less than you would with a "lighter" oil, but with lighter oil it's getting to the parts when cold. IIRC, and I don't know if this is true, rings on a/c engines have a wider gap because they run hotter/will expand more, so yes, a/c engine will use more oil then w/c. You'll need to add more in any case. Finally, I don't believe oil is meant to "absorb" pounding as much as its meant to reduce friction/heat by it's visoscity, ie ability to cling to metal. As always, YMMV.
 
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