Why not use OW-x all the time? (Indian Chief owner

[SkipII]

This is my first time on this forum and I was fascinated by Bob's thorough explanation of viscosity and the fundamental differences between mineral and synthetic oils in maintaining their viscosity.

But it raises an interesting question...

If the lower number is a measure of an oil's ability too flow at colder temps and the higher number is a measure of its viscosity at operating temps, why used anything higher than 0W at allis using a synthetic? What can be the harm in having an oil that is at least closer to the 10 flow rate when cold, as long as it has the same when hot?

I have an Indian Chief Vintage, which is notorious for having a sticky gearbox when cold, and it is because the clutch plates get gummed up with cold oil in the first few minutes of operation. (Indian Thunderstroke engines have a shared sump with engine and gearbox, so they do want a specific motorcycle oil that does not have the friction inhibitors,but that seems separate than viscosity).

As well, if Bob is correct (and I think he is!), why do manufacturers persist in recommending 10W or even 20W (in the caae of Polaris/Indian) if the science shows that flow rate is too sluggish? And why does Indian (or others) recommend a blend?

 

[SuperSalad]

Why indeed.

The trouble with the lower winter ratings is that many products will shear more the lower the W grade. This isn't true in all cases, but it isn't uncommon for lower W ratings to exhibit more viscosity shear. Different brands will give different results depending on the viscosity modifiers they use.

 

[Shannow]

Sorry that was your first introduction to the place, there are some errors that you have been exposed to.

the "0W" is the "Cold Weather" performance of the oils, at their extreme limits of functionality. It is made up of two tests, the CCS (Cold Cranking Simulator), which is a measure of how poorly a typical engine cranks at a given (very cold) temperature. MRV is a measure of how well the oil can flow into the oil pick-up tube, and to the oil pump - that's the pumpability.

These test temperatures are respectively.
0W, -35C, -40C
5W, -30C, -35C
10W -25C, -30C
15W, -20C, -25C
20W, -15C, -20C
25W, -10C, -15C

So you can choose a "W" rating based on the minimum temperature you expect in your OCI.

At temperatures well above these limits (say freezing), you can expect oil to "flow" to all parts of your engine at about the same time. e.g. Mobil 1 0W30 and 5W30 are virtually identical in all respects for viscosity bar their ability to pump at -30C basically...the concept of theor flow rate at realistic riding temperatures being "too sluggish" is incorrect, and fearmongering really.

101 claims that synthetics don't have products called "viscosity index imporvers"...that's false, as they and minerals do...they might have a little less but still typically have them.

The disadvantage of having them in a shared sump is that these VII molecules are long polymer chains, typically thousands of carbon atoms long. They can and do get sheared (cut to pieces) in service, and shared sump applications are some of the worst conditions for them.

The "10" is a made up number that the author has never defended when challenged...he makes no mention (except incorrectly) to the High Temperature High Shear Viscosity, oft listed in brochures. This is the viscosity that's apparent at the shear rates in things like big ends, and at a temperatures of 150C, which aren't uncommon in big ends...It's usually in the range 3-6, 3.5 to 4.5 being pretty typical for bike manufacturers.

Your manufacturer is cogniscent of all of these competing requirements, and knowing that you aren't likely riding at -30 to -40C has made recommendations that they feel are appropriate.

 

[OneEyeJack]

I use Red Line oil and for similar spec's at the same price I use 0w-30 instead of 5w-30. I have no idea if I'm better off but I'm okay with my decision.

 

[Oro_O]

To give a graphic representation of Shannow's excellent answer you can take a look at this graph. It is copied from an SAE paper on this and represents typical convenional motor oils at degrees fahrenheit.

For most ambient temperatures at which vehicles are operated, there isn't a difference in most oil grades. The trade-offs made (more VIIs/thinner base stock) are not worth it unless you need the cold-weather performance.

 

[BrocLuno]

Your oil pump is a positive displacement unit. If the oil is fluid, it pumps the same amount whether is 10W or 30W (cool/cold oil). In any kind of weather were you'd feel comfortable riding for more than 10 minutes, even with a snow suit, you will never need a 0W, or even a 10W.

15W is liquid at minus temperatures and flows just fine. Ask all the heavy duty diesel truck guys trying to start south of the Arctic Circle... It's used year round in big rigs all over the county.

I think your question should be rephrased - why run a multi-grade oil at human temperatures (riding temps). There is no real reason to. SAE 30 HD oil would be fine as long as your engine MFG allows 30 grade in the mix in the owners manual. No shear at all - period. Stable near 100% oil without things that are not oil like VII's.

Bikes present peculiar problems because they share crankcase, clutch and transmissions. If yours has separate primary and tranny, all the better.

My Harley like thick'ish oil for the engine - say 20W-50 most of the time. I can get away with Castrol 10W-60, but it's slightly noisier on cold start. I like quiet smooth engines. I like narrow grade spreads with as few VII's as I can get.

Most oils for cars and trucks do not really address motorcycle engines. They are primarily for plain bearing lowers. Most motorcycles have roller or ball bearing lowers, so the oil requirements are somewhat different. But over time it has been discovered that many HDEO's (15W-40) work well in some bikes. They might in yours. Only trial and error will tell what the motor is happiest with

Listen to the motor cold and hot. Find the oil that makes it quietest and smoothest under the broadest range of conditions. That's your oil.

If you have a separate tranny oil reservoir (?), that is separate from the primary and clutch, you can try Redline MTL in the tranny. Your shifting issues will be gone

But if it's shared with the primary it won't work. It will louse up your clutch engagement ...

And just for reference, you do know how they make oil right? They start with base stocks that will pass the W rating and add viscosity index improves to get the hot rating they want. Once they shear down, all you have left is the base oil. Do you really want your Indian running around on 0W oil ...

 

[SkipII]

So, Bob The Oil Guy is not right? Darn, Santa Claus, the tooth fairy, and now this...

I was going by Bob's 101 article that made the case that oils are markedly too "thick" when cold -- well about what he called the ideal 10 viscosity at operating temps of 212 degrees. No, I don't assume my air-cooled 1811cc engine has the same temperature at operating level, but I figured it was somewhere in the ballpark, even if a bit higher.

But it led to me conclude that an oil with aW number of 10 or lower would more likely have a better flow than 20.

Some of the responses here basically totally content with that assertion and say that oil of 20W flows just fine. So I'm confused as to why he has a chart and a narrative that states otherwise.

Or, I can just forgo all this and just ride the thing! The only reason I raised it is that the bike does have an idiosyncrasy where it is nearly impossible to shift it out of first on a cool/cold day for the first mile or two because the oil is still to "think" and does not fling off the clutch plates. (Yes, Indian is shared sump.)

 

[EdwardC]

I always thought that even with a positive displacement pump, a thinner liquid would be easier to pump than a thicker one.

Either way, it sounds like you have a very specific issue, poor shifting while cold. With a shared pump, the oil directly affects that. I would just try a lower winter rated oil and see.

I noticed that with my old bike, as the oil sheared, the shifting got notchy, prompting me to replace. I never really had issues with shifting while cold.

 

[Robenstein]

I have seen some bikes have a sticky clutch with some oils (my old Yamaha Virago was one). Or you may have a clutch that is just a bit out of adjustment.

 

[Shannow]

Originally Posted By: SkipII
So, Bob The Oil Guy is not right? Darn, Santa Claus, the tooth fairy, and now this...

I was going by Bob's 101


Unfortunately Bob didn't write that article.

You can read more articles by the author of University 101 here...

 

[SkipII]

I probably invited solutions to the clutch issue by raising it, but that was just to give me question some context. I am deeply researched on that issue and have been involved in several high-level discussions at Polaris about it. It is not my only interest.

My reasons for my post was to understand some facts. I still am puzzled about the 101 article that seems to indicate that only the lightest (0W, 5W) synthetics come close to the "ideal" 10 weight (at least for 212 degree operating temp engines) in cold conditions. Others here are saying that doesn't matter, the oil will flow in all but the most extreme cold.

My point (or question) simply was that if a synthetic oil with a 30-weight on the high side will maintain that under time and heat, why not go with the lightest W viscosity rating to protect the engine during start-up?

Or put another way, as long as I use a synthetic that has at least the recommended viscosity on the high side (in this case, 40) what is the harm in going as light as possible on the low/cold side? If the charts are correct, even the lightest oils are still thicker when cold than the desired operating temp viscosity.

 

[Shannow]

You are right...that's what 101 says.

Please report back on your 0W40 shared sump experience.

A Used oil analysis would be handy, run it full OEM Oil change distance, and I'll put $30(US) towards the analysis.

 

[Atesz792]

It will end up a 0w-20 or worse (that's permanent shearing) within 1000 miles, that's why.
Shifting becomes notchy, your gears could start pitting, and that's a downward slope...
The mfgr knows this. They also know the recommended stuff will shear a bit too, but it'll still protect adequately afterwards.
Do a search on Shannow's posts, he has explained this very well a thousand times, bet he's tired of it by now.

 

[Robenstein]

As mentioned the problem is not time and heat, but shear caused often by the nature of unit construction/shared sump designs.

A 0w50 for instance will hold up well in terms of viscosity in a non shared sump design like some BMW's and Harleys. But toss that same oil in a shared sump Yamaha V twin cruiser that uses engine oil to lube the engine and transmission and the tranny gears will grind up that oil and spit it out a full grade or more possibly if you have other issues like fuel dilution.

That being said if you are a warm weather rider, a 10w40 will most often hold up better than a 5w40. The general rule of thumb is the larger the spread in viscosity, the quicker they will shear versus an oil with the same base stocks but with less spread.

 

[Spur]

I also have an Indian with the TS111 engine. You have some very knowledgeable folks commenting here. I would be interested in the UOA on a 0w40. I have always thought they would shear too much.

I run Delo 15-40 and have posted UOAs in the motorcycle section. The UOAs have been very good. I usually run the oil about 3000 miles and use a fram XG7317 that I change every other oil change. The clutch feel and shifting feel good to me with this oil. I would be equally comfortable running, SRT5, delvac or Delo. I just kind of like the chevron chemistry a little better.

I am probably changing the oil too often, but it gives me something to do. The Indian Chieftain is so trouble free, that's about the only thing I get to do to it. At $12 dollars a gallon, it doesn't cost much to do. Considering only changing the filter every third oil change. It is rated for 15,000 miles.

Good luck Skip, let us know how it turns out.

http://www.bobistheoilguy.com/forums/ubb...vro#Post3737079

 

[Oro_O]

Originally Posted By: Shannow

Unfortunately Bob didn't write that article.

You can read more articles by the author of University 101 here...


Priceless...

 

[KrisZ]

You guys do realize that the number before W is for winter low temperatures, we're talking well below 0F, not just "California 40F cold" right? It does absolutely nothing in above freezing temps like pretty much 100% of motorcycles are operated in.
There is no better flow, better cold start protection. None of that applies to motorcycles. Of course there is one member that will argue that 0WXX oils allow the use of full power sooner and that he's seen engines fail on the race track with thick oil in them and not to the operating temp. but it was never substantiated and still hold the status of a fairytale.

 

[Shannow]

Originally Posted By: SkipII
Or put another way, as long as I use a synthetic that has at least the recommended viscosity on the high side (in this case, 40) what is the harm in going as light as possible on the low/cold side? If the charts are correct, even the lightest oils are still thicker when cold than the desired operating temp viscosity.


OK, a couple of examples...from a Mobil blending guide (note guide, not recipe book).

First one is for small engines, and motorcycles.

Look at the two 0W30 brews versus the 10W30 brews...both are "30" hot, and clearly the difference is in the "W" part, and how they get it.

The two 10W30s use a base-stock of about 7-8cst, and the additive package at around 10.3(+) percent.

The two 0W30s use a base-stock of 4.5 to 5.5Cst, a lot thinner, and have 5-7% Viscosity modifying polymers, to get the viscosity up to a 30 hot.

These polymers aren't necessarily stable in gear boxes, and end up getting sliced up, which drops the viscosity away from 30 hot...and as the oil has a much lower base oil viscosity, there goes your protection down the toilet.

Also, the 0W30 with it's lower base oil viscosity will have a higher volatility, more evaporation, and probably slightly higher oil consumption and deposits.

So I'd personally recommend that you don't chase the 0W part in a shared sump application unless you really DO plan on riding at -25C.

10W-40 is one of my least fave grades also, for the same reasons.

Here's the passenger car sheet...posted as it's got more information, and there's a couple of advocates of using M1 0W30 passenger car motor oil in their bikes.

Look particularly at the 0W30 versus 0W40...the 0W40 is actually a thinner basestock than the 30, and nearly double the Viscosity Modifiers.

Thus I would never suggest actually running it shared sump.

 

[AMC]

Shannow- Thanks for the clear response.

With what you said in mind, how do you think a 15w-40 would fair in a shared sump bike at 40F / 4.5C, the coldest most people are willing to ride?

Would something like a 5w-40 really be worthwhile or no, just stick to 15w-40?

 

[Shannow]

AMC,
the 15W40 is going to be more shear stable for sure (hope sunruh chimes in, hes got some really great field data).

But with an HTHS of 4.4ish, versus 3.8 for the 5W40, you'll lose some small amount of power (and economy), and generate a little more heat as a result...but will have greater film thicknesses throughout.