[Sabre-t]

Amsoil here. Getting it from the right sellers and it's as cheap as anything else (Mobil 1 or Valvoline that is). I buy it by the case for that much more of a discount. My personal opinion is that a motorcycle-specific conventional oil will offer much better protection of the wet clutch, transmission and overhead cams than diesel engine synthetic oil. JASO-MA is the bare minimum for wet clutch operation; but has nothing to do with the other unique properties of our engines. Oil designed for slow moving, high compression engines is going into bikes with very fast spinning overhead cams. It's certainly no skin off my nose; but I think that marketing has sung people to sleep with the notion that 'synthetic' (which is just a word slapped on a bottle anymore) is so much better, that it's somehow better than a motorcycle specific conventional. When in fact, the MC specific conventional oil will offer much much better protection. (And MC specific synthetic even better; but if we're talking like-for-like pricing).

One thing to note. Some are ALSO sucked into marketing gimmicks for "V-Twin Oil" and buy heavier weight oil than what the manual recommends. Our metric cruisers actually have a lot more in common with sportbikes than Harley-Davidsons. Shared oil between the engine and transmission, overhead cams, most Vulcan engines have a fairly high top end RPM too (the VN900 hit's 8k, and the 1700 revs faster than a Harley-Davidson 106"). The V2K is a little closer; being a slow revving lumbering engine; but the rest really would be better off with the oil marketed for 'sportbikes', with those additive packages. And running what the manual recommends; which on most bikes is 10W-40. Some misread the manual and think because it sometimes, once in a while, during the hottest part of the summer gets 'that hot', they run the oil for those conditions. But ultimately they are sacrificing protection to run the oil that's ideal for 2 or 3 days a year instead or running the oil that's best for the other 360+ days of the year. (Except, of course; for those in truly very hot climates; like Death Valley or southern Florida/Texas).

Just my $0.02. I'm happy with Amsoil but I was happy with Valvoline and Mobil 1 too. Any of the premium synthetic motorcycle specific oils will offer excellent protection.

I just did a used oil analysis on my wifes bike (for the fun of it). She has 9k miles on her bike. I change the oil in hers once a year (she only rides a couple thousand miles a year). After about 4,000 miles and a little over a year; the oil came back (Amsoil) still in grade with the additives still plentiful. They said I could've easily gone much longer; and the metal in the oil (which helps determine wear) was well below average from a 750 Honda with that many miles. So it appears to be doing its job!

I just wonder why so many folks say that 20W-40 or 50 is too heavy for the 1700s and that we should use what the manual recommends. Well, the manual recommends both for certain temperature ranges. The pic below is from the service manual for the Voyager. The general recommendation is for 10W-40, but is followed with advise to adjust according to conditions:

"Although 10W-40 engine oil is the recommended oil for most conditions, the oil viscosity may need to be changed to accommodate atmospheric conditions in your riding area. "

I do agree that 20W-X is too heavy for winter riding and I change to 10W-40 before the temps get anywhere near freezing. However, according to the pic from the manual, I shouldn't ride at less than 14° F, even with 10W-30. Oops! I rode at 10-12° (with 10W-40) on multiple occasions (also shown at down to 14°).

Amsol touts their own 20W-50 as "providing superior performance and protection" for motorcycles. They don't even suggest that it should not be used in colder climes.

https://www.amsoil.com/shop/by-product/motor-oil/gasoline/premium-protection-20w-50-synthetic-motor-oil/

 

[Sabre-t]

The main difference between motorcycle oils and automotive oils is (supposedly - see the next paragraph) the amount of ZDDP (Zinc Dithiophosphate) and the addition of friction modifiers to auto oil. ZDDP acts as a last gasp measure to reduce wear of metal on metal. What this means is that as the oil breaks down, it provides less lubrication. ZDDP extends that protection a little longer than the oil would otherwise provide. With the advent of synthetic oils, especially fully synthetic oils, ZDDP is less necessary unless you do not change oil often enough. It still helps to reduce metal on metal wear, but it is not nearly as important as it used to be if you are using a synthetic oil. It is very important if you still run a traditional oil and go more that about 3K miles between oil changes.

ZDDP concentration in oil is regulated. It causes damage to catalytic converters. Many motorcycles have catalytic converters, so it is regulated to the same extent for motorcycle or automotive oils. It has been a few years so I don't have any links, but I saw the data from testing of a number of auto and motorcycle oils. The amount of ZDDP within a brand of oil and type (traditional or synthetic) was pretty consistent without regard to being auto or MC oil. The main difference between the auto and MC oils was the friction modifiers.

It sucks that we have to pay more to have friction modifier additives left out.

 

[Sabre-t]

That is the point you don't, I run Rotella T6 5W-40, does great.irate:

I have had bad results for other Shell Rotella versions in the past with another bike. T6 may be better than the ones I used, but I don't care to risk their products again. I like Royal Purple, but they do not have 10W-40 or 20W-50 without friction modifiers except for the MC versions. My opinion, but I don't think 5W-40 provides adequate cold cranking protection unless a vehicle has been specifically designed to use an oil with 5W cold viscosity. Oils with cold viscosity that low do not leave enough of a film on surfaces when the engine cools off. Like I say, that is just my opinion.

 

[Sabre-t]

Whut??????? Engine off, no pumping, Oil hanging on to parts for dear life waiting for next crank over... film strength of straight 50 vs 5w would be about the same after a couple of days. There is no oil there. Sha-boom. Fathom that.

Respectfully, I totally disagree.

 

[Sabre-t]

It's been quite a while ago but I believe it was Mobil 1 full synthetic, but now I'm wary to try it again.

There are a number of full synthetics under the Mobil 1 brand. A couple are for motorcycles and would not have friction modifiers. Some are for cars with and without friction modifiers. If you used one of the ones for cars, it's quite likely that you used one with friction modifiers.

You can get oils that are not full syn that have friction modifiers, so just staying away from full syn and not educating yourself on what to look for in a motorcycle oil can land you in the same situation again.

 

[Sabre-t]

This is the truth from Oil engineers!

How 10w30 Oil Affects Equipment

Although understanding oil viscosity is important in solid fleet maintenance, oil viscosity also affects the performance of a wide range of industrial equipment. For example, viscosity can increase or decrease the heat created by bearings and cylinders. Viscosity can also affect how quickly oil is consumed and how easily equipment can be started and operated in extreme temperatures.

When the oil has a higher viscosity, or is thicker at warm temperatures, you will use less oil and experience less wear and tear on your vehicles or equipment. However, a thinner viscosity oil can help improve the start-up of a piece of equipment as well as reduce fuel usage.

Inappropriate oil viscosity can result in occasional contact between machine components. When this goes unchecked, you’ll start experiencing damage and problems with equipment. As a result, it's important to not only select the right type of oil for each application, but also to conduct regular oil changes in your preventive maintenance program.

No one is arguing that the appropriate oil weights need to be used. Your earlier statements just did not make sense. They were also, at least partially, incorrect. Oil weight does not affect sheering to a significant degree. The base type of the oil does. Conventional oil sheers more quickly than synthetic oil of the same weight. Muti-weight oils are needed to make sure flow and surface adherence are correct at different engine temperatures. Each engine is designed to use a specific viscosity oil range. A car that uses 0W-30 would be damaged as much or more by using 10W-40 as a motorcycle that uses 10W-40 would be damaged by using 0W-30.

 

[Sabre-t]

It's grade, not weight. Viscosity=grade.

that little "W" is for "winter"

..... and most synthetic oil sheers less than conventional oil. Not all.

and more....

www.bobistheoilguy.com

Potato, potato (say the difference in your head). Both are tied to viscosity. For non-petroleum chemist talk, they are interchangeable. The numbers represent specific viscosity ranges at specific temperatures.

As you say, the "W" in a multi-weight oil does not stand for weight, though. Originally, it stood for "Winter." Bad choice since multi-grade/weight oils are needed year round if needed at all.