Conventional 20W50 For Harley Davidson

I've rebuilt a lot of Harley engines over the years and had the chance to observe a lot of riders using a lot of different oils over time. Barring egregious foolishness (like the guy who ran the cheapest 10w-30 he could find or the guy who ran gear oil because it was heavier and therefore better) with one exception it is less about the oil and more about the person's riding habits and maintenance habits.

The exception first -- certain oils do not work with the cam profiles on Harleys. Think about the difference in the wear surface between a relatively low lift overhead cam and a relatively high lift cam with roller tappets. The wrong oil results in skating on the cam lobe ramps and as the valve springs weaken you start seeing bounce at the top of the lobe and the hard facing starts shattering. This causes a lot of wear and damage, far more serious than choosing 10w-40 rather than 20w-50.

It's worth noticing that there are plenty of Evo engines that went well over 200,000 miles on HDEO multigrade, I rode one that had been on Rotella since it was new, it had a little over 249,000 miles on it and other than repairing one leak it had never been touched with a wrench except to change oil and spark plugs and it ran like new.

The main sources of damage I've seen over the years in order of significance:

1) Revving the engine at cold startup. Let it warm up just a little bit first.

2) Rough treatment. If you are going to do hole shots or burnouts or wheelies at least load the drive train up a little first and have some finesse with the clutch. Taking the slack out before you apply power reduces damage greatly.

3) Oil change interval in hot weather. Harley published some guidance from the factory school when they first started recommending multi-grade oil that said every 20 degree increase in oil temperature over a certain point cut the oil life in half. I don't know if that still pertains, if the chemistry has changed, or the research indicates something different, but I can say with certainty that people who shorten the OCI in hot weather tend to get more miles out of their engines before a rebuild is required.

4) Too much oil and/or too much oil pressure. Whether it is oil that is too heavy for the climate or any of the aftermarket gimmicks that pander to "more is better" mentality, too much oil and/or too much pressure is rough on these engines. Roller bearing bottom ends just need to be wet, that is about all. I've seen bikes run for years with the oil light coming on at a low idle. There is a reason why Harley sets the relief valve pressure the way they do. And yes, if hydraulic lifters are clattering at an idle it's worth making sure they are getting the design flow (like clean the tappet oil screen on an older engine) and consider using a heavier oil under those conditions.

If you follow the manufacturer guidelines for oil type and viscosity and change it at the required interval or sooner under demanding conditions you're going to be fine. Any of today's premium name-brand oils formulated for V-Twin motors are going to work. I am careful about using automotive (passenger car) oils, the savings on the cost of the oils doesn't even come close to the cost of the damage I have seen if you choose wrong. As for HDEO, there is no reason to not use it in moderate climates if you are inclined that way, it works great up to about 80 degrees ambient.

To the OP question, I run Valvoline VR-1 (their racing oil) in the engines I have bumped up a bit, the oil is quite reasonably priced, it seems to hold up well in engines that are running hotter or under higher compression, and I just change it a little more often. Upon disassembly what I am finding is an engine that is worn as expected (tolerances all a little wide) but no scoring, even wear on pistons and cylinders, no unexpected discoloration anywhere, no mechanical damage to bearing surfaces, no shattering on cam lobes, the engine looks great, just worn out.

Everybody has their preference, anecdotal evidence abounds, and I am certainly not going to advocate one brand of synthetic 20w-50 over another. Just offering my own experience, maybe it will be helpful.

A little more background on oil selection for V-Twins, folks who were riding when Shovelheads roamed the earth may appreciate this.

A Harley V-Twin, at least until the advent of the Twin Cam, is basically a slice out of an aircraft radial engine. Close enough for our purposes here, anyway. Common crankpin, roller bearing bottom end, air cooled, long stroke, overhead valves and pushrods, dry sump, this is a very different sort of engine from an inline short-stroke DOHC four cylinder. If you look at a Harley factory manual from the 1970s it talks about the necessity for a high detergent low-ash oil. It occurred to more than one of us that this sounds a lot like aircraft oil.

For sure some of the aftermarket manufacturers did have some trouble with hardness on their cams, combined with "performance" profiles this did lead to some early failures. But some of them were renowned for reliability, every bit as good as the factory cams, in some ways better.

We ran AeroShell for years on all kinds of bikes in punishing temperatures and never had a problem, even with oils that were a little light by modern standards. The we tried Phillip 66 (this was years ago) and the cam lobe and roller failures happened soon there after. I always wondered about this, I think it was someone here who clued me in to the difference in additives.

For anyone who doubts, there's this:


They're putting additives in now for cam wear? Who knew?

Something similar happened when the additives in passenger car oil was was changed for catalytic converters. Motors that did fine for years on conventional 20w-50 suddenly didn't.

As I mentioned, I'm not trying to persuade anyone or change anybody's mind or tell anyone they are wrong, it's your bike, do whatever you want. But since the question was asked, maybe this info and experience will help anyone who is interested avoid some unnecessary expense and down time.
 
A little more background on oil selection for V-Twins, folks who were riding when Shovelheads roamed the earth may appreciate this.

A Harley V-Twin, at least until the advent of the Twin Cam, is basically a slice out of an aircraft radial engine. Close enough for our purposes here,

For anyone who doubts, there's this:


They're putting additives in now for cam wear? Who knew?

Something similar happened when the additives in passenger car oil was was changed for catalytic converters. Motors that did fine for years on conventional 20w-50 suddenly didn't.

As I mentioned, I'm not trying to persuade anyone or change anybody's mind or tell anyone they are wrong, it's your bike, do whatever you want. But since the question was asked, maybe this info and experience will help anyone who is interested avoid some unnecessary expense and down time.
One has to remember Piston Aircraft oil has no metallic anti wear agents in it.
No Moly, No Zinc no anything with metal as an antiwar additive. So it cant be compared like you are referencing.

I do sometimes remind others when looking for a lot of these elements that piston aircraft oil doesnt have them when they make posts on how "stout" an automotive oil looks and pay extra money for expensive oil containing large amounts of these additives that airplanes dont use them.
How perfect of an example can that be, airplanes dont use them! DOnt want them to fall out of the sky! *LOL*

Why? Because all that anti-wear metal in automotive oil (ex. zinc/moly) can lead to piston ring/piston deposits. Aircraft makers and FAA are aware of this. There is also pre-ignition possibilities with these deposits as posted by molecule.
SO goes the saying, for those looking for loads of it in their automotive oil, there is such a thing as too much.

Here is a really old thread ... UOA not exactly perfectly typed out, Im looking for another .
 
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Any quality API approved 20W50 oil is perfectly fine in a Harley motor. Main thing is to change it often as it's an air cooled engine. No need to overthink this.
 
Any quality API approved 20W50 oil is perfectly fine in a Harley motor. Main thing is to change it often as it's an air cooled engine. No need to overthink this.
Funny you said this as Harley's own factory recommended branded oil isn't API approved, and their bottles do not carry the API Donut. The only other oil Harley will consider acceptable to use in their engines is Diesel oil. And the factory recommended oci is at 5 k miles. So if your using a quality oil, you shouldn't have to change it any more often than what the moco says. They seem to know what works, and how long oil lasts in a air cooled motor. But when you consider how many brands of Motorcycle oils there is on the market, alot of oil producers know it also. You won't find any proven claims about engine failures due to not using Harley's oil, or pretty much any other brands for that matter.,,,
 
Funny you said this as Harley's own factory recommended branded oil isn't API approved, and their bottles do not carry the API Donut.
Does it have any 3rd party approvals ... or is it just "approved" by HD? What's a VOA show on HD oil? Seems like a way to market the sale of HD oil.
 
It has Harley's approval, they feel that's all it needs. No mention of meets or exceeds anything. Harley markets their oil in their dealerships. And unless you can convince them otherwise, any oil change you get at a dealership, will be with Harley oil. The sell alot of oil in the course of a year at the dealerships. I really don't get why with all the brands out there and with all the VOA's and UOA's just on this site, they won't recommend anything but diesel oil if their oil isn't available. Almost seems like a misprint in the manual when you read about using diesel oil.,,
 
Harley engines are air cooled, this is true, but it is only partially true. They are also oil cooled, this is something that was emphasized in factory school guidance to dealerships. If you think about these being dry-sump engines with an external oil tank and you think specifically about how the oil is circulated the difference will become clear, and it will be easier to understand why the manufacturer's recommendations are guidelines that you may want to modify depending upon your circumstances, inclination, riding habits, and how you want to care for your own bike.

A water cooled wet sump engine dissipates heat differently than a Harley, and the result for the oil is different. Oil that is designed for a water cooled wet sump engine might not be your best choice.

If you think about a V-Twin engine it should be clear that if the bike is lightly loaded at moderate and varied speeds on a cool Spring day the cylinder head temperature will look one way and if you are stuck in traffic on a heavily loaded bike and the ambient temperature is over 100 degrees and the asphalt temperature is over 140 degrees the head temperature is going to look another way and if you are running for long periods of time at high speed at a steady throttle setting it is going to look yet another way.

That oil is being circulated over those heads of course. If you install a temperature sensor on the heads and on the crankcase you will see the temperature of the engine is far from consistent.

The point to the information that the factory school was sending to the dealerships about oil life being cut in half for every 20 degrees past a certain point was just this -- what works for one rider and one bike in a certain situation may not work for another rider on another bike in another situation. Someone who does not push their bike hard under severe conditions is probably going to be fine with any appropriate oil that is changed at the recommended interval, as has been pointed out here many times.

But what works for a gentle occasional rider in a temperate climate is not going to be a good maintenance plan for someone who is pushing their bike hard, or operating under demanding conditions in more severe climate, the difference in oil life does show up in the longevity of the engine.

Part of getting the most life out of your engine before major repairs are required is using the right oil for the circumstances, part of it is changing it according to those circumstances, and part of it is riding habits like I mentioned earlier. I've rebuilt a lot of HD engines that were badly damaged far earlier than what should have happened because the riders did not know or care about this, many more of these than engines that were simply worn out. The engines that gave full service life and were simply worn out from high mileage had clearances well in excess of the service wear limits but very little in the way of visible mechanical damage. The engines that had the wrong oil, oil that was not changed often enough, or riders who were beating up their bikes, the mechanical damage was obvious.

There really isn't any hard and fast rule, there is no one-size fits all answer, if you are a gentle rider in a moderate climate there probably isn't much reason to give this a lot of thought, just follow the recommend maintenance schedule. But if you are running the bike hard or riding in a severe climate then the least expensive thing you can do is use good oil and change it a little more often.
 
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The point to the information that the factory school was sending to the dealerships about oil life being cut in half for every 20 degrees past a certain point was just this -- what works for one rider and one bike in a certain situation may not work for another rider on another bike in another situation. Someone who does not push their bike hard under severe conditions is probably going to be fine with any appropriate oil that is changed at the recommended interval, as has been pointed out here many times.

But what works for a gentle occasional rider in a temperate climate is not going to be a good maintenance plan for someone who is pushing their bike hard, or operating under demanding conditions in more severe climate, the difference in oil life does show up in the longevity of the engine.

Part of getting the most life out of your engine before major repairs are required is using the right oil for the circumstances, part of it is changing it according to those circumstances, and part of it is riding habits like I mentioned earlier. I've rebuilt a lot of HD engines that were badly damaged far earlier than what should have happened because the riders did not know or care about this, many more of these than engines that were simply worn out. The engines that gave full service life and were simply worn out from high mileage had clearances well in excess of the service wear limits but very little in the way of visible mechanical damage. The engines that had the wrong oil, oil that was not changed often enough, or riders who were beating up their bikes, the mechanical damage was obvious.

There really isn't any hard and fast rule, there is no one-size fits all answer ...
So are you saying ignore the owners manual and listen to people in BITOG?
Is Harley saying to ignore their oils requirements?
I would say no to both the above.

This is a 3 year old thread by the way and this argument will never end regarding motorcycles, it finally has ended with automobiles for the most part. I suspect because most automobiles are serviced by service places and not the owners, so the service places put the recommended oil in the engine, the automobile engines now last longer than the vehicle itself, unlike motorcycles where we have an endless debate on what will make an engine last longer.
We all know, properly designed engines by the manufacturer last a long time, in regards to motorcycles, normally longer than the owner owns it.

To me its real simple, use the recommended oil and your (in this case) motorcycle will give you a long life, no oil will make up for bad engineering if that is the case. Will using a non recommended oil hurt? I doubt it just like automobiles, use whatever you want or go with the manufacturer recommendation. I prefer API rated oils. Whether an automobile, bike or boat or plane, they will all give good service with what is in the owners manual and if you dont use what is in the owners manual chances are you still wont notice a difference, more so if its the same weight and API rated.
 
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Any quality API approved 20W50 oil is perfectly fine in a Harley motor. Main thing is to change it often as it's an air cooled engine. No need to overthink this.
But this is BITOG !@! We are all smarter than the other 99.9% of the population whom also own vehicles that go hundreds of thousands of miles using plain Jane factory recommended oil
*LOL*
BTW = yes, I agree any 20w50. I do for my own "thing" use the diesel oil since there is a mention of it in the manual so that takes me to a Mystik JT8 15w50 semi syn and the cost is the same or less than conventional 20/50 for me. Either way, either one. I buy it in 2 gallon jugs and now serves two purposes as I use it in my boat too.
 
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But if you are running the bike hard or riding in a severe climate then the least expensive thing you can do is use good oil and change it a little more often.

Yes this. I treat all my bikes the same by running the very best oil I can afford and changing it often. Sadly, the average Harley owner rarely runs hard or knows the meaning of extreme riding. It's not often you see a Harley rolling across the desert doing a 500+ mile day loop in 100+ deg heat.
 
The only TRUE way to know if your oil is depleted of it's protection capability's is to perform A UOA. Anything other than that your just guessing. It's been know for years that Harley torturers their bikes in testing ground situations to make sure in the real world, what they can handle. That's with using their branded oil, which has been proven to be nothing extraordinary. And they still go with the 5k mile recommendation. Claiming that using their Synthetic oil is even better than their mineral base oil. Still no change in the factory recommended OCI of 5k miles. Apparently Harley's oil filters do their job of filtering and crumbs and barnacles out so that helps keep the internals from grinding together. Defective parts from the factory probably make for internal repairs, that any brand or weight of oil couldn't help. I personally have a lifter wheel come apart and spew needle bearings inside the engine. The oil level was fine. I've also had cam shoes wear out. Now I know they are plastic, and oil can only help them slide to a point. And lets not forget about twisted flywheels on their pressed together versions. Again oil can't be held responsible for bad engineering. You could have changed your oil everyday and it wouldn't have changed the outcome of the things I listed.,,
 
Yes this. I treat all my bikes the same by running the very best oil I can afford and changing it often. Sadly, the average Harley owner rarely runs hard or knows the meaning of extreme riding. It's not often you see a Harley rolling across the desert doing a 500+ mile day loop in 100+ deg heat.
Well, honestly I ride in 95-100 degree heat (never less than 90) quite often late June, July and August and moving at 80 MPH the oil is cooler than when you are stuck in beach traffic and barely moving. On my 2014 Road King and 80 MPH it will run up to around 250 degrees +/- 5 degrees

Stuck in traffic and it will run up to 270 degrees +/- 5 degrees, for bad traffic I do have a lenale engine fan that will stabilize the temp around 270. Depending on outside temp sometimes will bring it down to 265.

Since my oil is so inexpensive I change it every 3000 miles, sometimes way less, sometimes a little bit more, though rare. Depends on how much riding I get in. Its been a cold winter here and haven't been out much so I will most likely change out that oil with low mileage at some point before the BIG heat of the summer just to get some fresh stuff in there for 3 very hot months.

We have been to a lot of places in and around our states and close by states, Im starting to wonder how much longer I will be riding, seem to have "been there and dont that" but hate the thought of parting with the bike so most likely will keep it.
I love the idea of another post in here, that new Low Rider ST for more around town kind of bike.
Looking forward to seeing it at the dealer but kind of know I wont do anything like buy one.
One thing for sure, nothing like being on a bike, always brings a smile to my face.
 
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Well, honestly I ride in 95-100 degree heat (never less than 90) quite often late June, July and August and moving at 80 MPH the oil is cooler than when you are stuck in beach traffic barely moving on my 2014 Road King. 80 MPH it will run up to around 250 degrees +/- 5 degrees

Stuck in traffic and it will run up to 270 degrees +/- 5 degrees, for mad traffic I do have a lenale engine fan that will stabilize the temp around 270. Depending on outside temp sometimes will bring it down to 265.

I sometimes forget that lane filtering is not legal in a lot of the country. I'm fortunate my bikes are water cooled so no issues with overheating. Man that is some high temperatures for normal conditions. I only see those temps when I'm on single track at walking pace.
 
My .02 here. I had experience with both conventional and synthetic my my TC's. My first was stock T88--dealer said he put in SYN but the bike was running so HOT I had to go back. Throttle response was slower and the power felt anemic. The fills prior to this incident were HD SYn 3 or M1, both 20w-50 grade. Yes, I could tell the difference...so I went back and insisted to have it changed to SYN3.

2nd bike TC-95. Cams, tuned. Compression under 10. This bike always had syn oils over the course of 35K miles of use, mostly high speed touring. I did have it shut off from idling in summer heat one year. The BEST oil I ever had in the bike was ester based Redline V twin 20-w-50. Ran cooler, higher mpg, great response.

Older folks say ester based oils are ideal for air cooled motors with the ability to manage and dissipate heat. My individual experience backs that up. Many v twin oils are very good. IMO==Redline was best for me and that bike.
 
I sometimes forget that lane filtering is not legal in a lot of the country. I'm fortunate my bikes are water cooled so no issues with overheating. Man that is some high temperatures for normal conditions. I only see those temps when I'm on single track at walking pace.
Yeah, Im surprised that here in the land of the free (South Carolina) its still not allowed.
The last two miles (or three miles) of a 2 hour 80 mph run to the beach can get dead stopped in traffic right before the beach. When its real bad infrequently we would take the "bike" lane. After all we are on a bike :eek:) once in a great while a vehicle would get pissed because your passing a long line of cars and trucks.

Well, I got stopped last year taking the bike lane. :eek:)
I was just about to pull into a parking space reserved for motorcycles literally across the street from the beach and I saw the blue lights.
I have a lot of respect for the police and he could pick up on that, so my wife and I on the side of the road, he said someone called them about me riding the bike lane. (in the meantime another cops pulls up) I explain the traffic was brutal, the bike was cooking, I thought the engine was going to stall and I panicked and had to get moving. We were there for quite some time talking, I was sincere and he wanted my license and registration.
I asked if I was going to get a ticket ( I was thinking I may not being we were having a cordial conversation and I did not deny what I was doing)
As he walked back to his car with my info he said, well, lets make sure your not a felon or anything and will let me know. *L*
He came back gave me my info, said stay out of the bike lane and have a good day. I thanked him for his professionalism (lack of better words) and he surprised me by saying the same about me. So that was that.
My wife says I am like "teflon" for me, I treat police with respect, they really dont have an easy job.

Ok, back to the state of SC, yeah, it drives me nuts that there is no lane filtering... situations like this are uncalled for, btw the bike lane I am talking about is nothing more then a white stripe painted on the road that no one was using.

AS far as the high temperatures, Harleys are engineered for high oil temps, though it states 230 degrees as normal. But they are not engineered to sit with no airflow for long periods of time and why I installed the Lenale fan. Its rare that I need it but glad that I have it for those beach days, though it burns the crap out of my legs, the heat blowing off the engine is unmanageable.
BTW I have 5 or so UOAs on this bike in the motorcycle UOA section, these temperatures did nothing to the oil or wear numbers. Again, its not a common everyday thing for 265 to 270. Safe to say up to 250 IS normal everyday oil temperatures on the interstate.
Over 30,000 miles now, bike still runs like new and has NEVER needed a repair which surprised me too!

With that said, I did have a Yamaha VStar 1300 which of course is liquid cooled, I didnt have the overheat concern as much but one thing for sure, it was not any cooler for the rider and passenger, when that radiator fan would kick on and blow that hot air back towards us it was torture. But at least you didnt have to worry about over heating, but its very limited that these occasions happen and I kind of like the simplicity of air cooled, if I had more of that kind of traffic I would go more towards JUGGS engine fans.

BTW- I run Mystik Semi syn 15/50 last oil on the UOA was for the first time Mobile 1 15/50 as an experiment because I see claims of lower oil temperatures with full synthetic. Well, I could not document the oil being any cooler. At one point I thought maybe is was up to 5 degrees cooler but turned out to be unrepeatable consistently so I question if it was anything at all.
I constantly check oil temperature as a fun thing, no way was a full synthetic like Mobile 1 any cooler and/or/if it was it wasnt by much. With that said, if you see the UOA, wear numbers were impressive with the Mobile 1 but I could tell the engine was more nosy for sure. Kind of a little unsettling at times *LOL*
 
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My brother and I have recoded significantly lower jug and case temps with Red Line vs conventional oils. He chose a lower viscosity, too, though. That’s likely the main source of the temp drop, but it has not had an adverse impact on wear. If anything wear is lower. His riding is all highway, essentially NEVER in slow or stopped traffic.
 
If highway riding is mostly what what you guys do, that makes sense. Have you spent an hour or more riding at lower speeds, like in stop and go traffic to see if the lower temp claim still holds true?. More airflow like what you would get on the highway, should equal lower temps.,,
 
any branded 20w50 is superior.

20w50 has come a long ways, it is a good oil just like 15w40.
 
If highway riding is mostly what what you guys do, that makes sense. Have you spent an hour or more riding at lower speeds, like in stop and go traffic to see if the lower temp claim still holds true?. More airflow like what you would get on the highway, should equal lower temps.,,
You know, many years ago I thought the same thing but not true for the 2014 Road King with the 103 H/O engine. That engine runs 2014 to 2016 in all the touring bikes. King, Street and Glide.
As you may know I have the digital oil temp gauge. I like instrumentation, fun thing for me.
Anyway, I know my oil temperature almost in any condition now without even looking I can guess as I check it so often.

1. Of course, stopped in traffic is horrible and highest.

2. Next highest is actually 80 MPH but at 80 MPH it is stable, rock solid between 245 and 255 depending on outside temperature, which means here, early morning 245, afternoon and close to 100 degrees 255.
So I looked into this, trying to understand, why, at such a high speed my oil temperature is higher on the highway, when gobs of air is blowing across the heads and air being rammed through the oil cooler is the oil temperature higher than riding around town and it truly is higher, the SECOND I get off an exit ramp the temp starts going down.

So from what I read, at higher speeds, the oil pressure is higher and "oil jets" in the engine spray the bottom of the pistons to cool the pistons and these engines, curiosity of the EPA now burn very lean/HOT and need to cool the pistons.
Which of course heats up the oil. Once you slow down barely any oil is spraying on the pistons to cool them down and not needed, bike under less stress, less RPMS and most of all less wind resistance, thus oil temp drops.
The reason I looked into this so much was I always wondered why manufacturers of all brands do not install fans on the oil coolers and Harley in particular since most dont have water cooled engines.
Anyway, that is what I understand it to be and all I can say this is what happens on my bike in real life, with real oil temperature measurements.

3. As long as I am not stopped in traffic, oil temperature hovers around 230 but if I jump onto the interstate, 245 to 255 is the norm.

4. As you may know I have done at least a half dozen UOAs on my oil, they are ALWAYS good, I am not at all paranoid about high oil temperatures or running temperatures, Harley engines are designed to run the way they do. Bike has been spot on reliable, never a repair yet at over 30,000 miles.
With all that said it would have been nice to have a fan oil cooler for the stuck in traffic days but I suspect an engine fan is more effective. Blowing air across the heads.
 
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I sometimes forget that lane filtering is not legal in a lot of the country. I'm fortunate my bikes are water cooled so no issues with overheating. Man that is some high temperatures for normal conditions. I only see those temps when I'm on single track at walking pace.
I saw 270-280 degree oil on my Sportster crossing Kansas a few years ago...90 degrees, steady uphill, and 80-85MPH speeds.

Per a UOA, the SYN3 handled it with no issues.
 
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