That is the endless debate....

There is no "Best" oil, and there are no right or wrong answers about oil selection.... that is why you get conflicting advice from "experts"...

Bottom line, if you use an oil that meets API specs, and change it frequently, you will be fine...

I can't remember the last time I heard of oil quality causing a problem... Oils have come a long way in the last 30 years... yet some of the old urban legends still persist...

IMHO....

The difference between a quality dino oil and a quality synthetic oil boils basically down to two things..

1) The quality synthetic oil breaks down at a higher temperature than a dino oil. So with a higher thermal beak-down, it will work particularly well in engines that are worked hard, have high HP, and/or work in a high temp environment. I believe it will last longer and lubricate better than a dino oil in those same conditions.

2) The oil change interval can be extended with a quality synthetic oil. Dino oils are often 3500 mile change intervals and synthetic are often 5000 mile change intervals

If you want extended change intervals or better thermal break down resistance, choose a synthetic oil.

Since Harley uses an air cooled engine, I usually recommend a good synthetic oil.

Having said all that, here's what I do... I have three twin cam bikes;

On the 2016 Bagger, I have a high HP crate engine installed in it (135hp/151tq). I also put the most miles on that one, usually 5k+ a year. I use a quality synthetic (Motul 7100, 20W50) and usually have to change it at least once a year based on mileage, sometimes twice. Because it's a high performance engine, I change at 3500 mi. intervals.

I have an '03 w/ 95" big bore and an '01 with just a stage I. They get about 1500 to 2500 miles a year max. Since they are locally ridden bikes, and don't get a lot of miles per year, I just use a quality dino oil. I use Spectro 20w60. I change that oil once a year, regardless of miles, so that's why I use the dino oil in them.

Good luck with your decision... Just don't over think it or lose sleep over it....

 

Thank You very much, good advice,my Low Rider s 114 it says it can have same oil SYN3 in all 3 holes,not sure about that,any thoughts on it ,or Harley Formula+ , What's your thoughts Please.

 

Interesting enough, that is confusing. When Harley came out with SYN3, the bean counters at Harley said use it in all three holes. Hince, the name .

My bike came with an extended warranty and service warranty

They added extra for 6 qts SYN3.

Fast forward to around 2014 or so and Harley started listing SYN3 as a second choice in owners manuals.

Not sure why and it wasn't in all models.

Oil engineers say use non detergent gear oil in unfiltered boxes.

Any choices of 1 thru 3 work great. No one ever will know the difference.

What makes oil threads a problem is some have thin skin unless you promote their idea.

 

So would Motul 7100 20w50 synthetic,be ok in all 3 holes,like SYN3,or use Harley formula+ for transmission and Primary what do you think, Thank You

 

Not a clue or any experience with Motul 7100 20W50 SYNTHETIC. But if it's a high detergent motor oil, it's a 2nd tier oil according to oil engineer standards because there is no filter. In them, you want crud to settle and stick to the bottom. Not stay in suspension with the oil and stop in a filter.

Is there any proven statics to the above that it works Have no idea. Just what the engineers say.

 

Seems like good enough answers on this. Let's move on to heel/toe shifters and is a Sportster a girl's bike.

 

Interestingly, Harley used to say that you should not use synthetic oils in Harley motorcycles. Then they would repeat many of the old urban myths about synthetic oils in an attempt to keep Harley customers buying Harley dino oil....

Then, Harley came out with Syn3, and now synthetic oils became such a great thing, you should use it in all three holes..... I've been riding Harleys since 1978, and in time you will learn that not all of the advice HD gives is because they are suggesting something that is best for their motorcycles.... Often, it is just marketing....

Again, IMHO.....

I am not a fan of uses the same lubricant in all three holes... I believe each area needs a certain lubricant. Obviously you CAN use an engine oil in all three holes, but I don't believe it's the best choice.

I like a good multi-weight oil int the engine. I use a straight weight, non-synthetic lubricant in the primary (HD Formula+ is good) and I use Bel Rey products in my primary. I like to use a 75-90 gear oil in the transmission, again I use Bel Rey products in the trans.

Many believe that a synthetic oil in the primary can be bad on the clutch discs. There are some aftermarket, performance clutch makers that suggest automatic transmission fluid for their clutches, and some warn against synthetic lubricants for their clutches....

Harley used to warn against 140wt gear oil in their transmissions.... Now that they offer a 80W140 transmission gear oil for sale, it's the "way to go".... Hmm, sounds familiar to me...


There are a lot of "shades of gray" in choosing a lubricant.... Decide what lubricant you want to use where, pick a quality name brand that matches required specs, and then enjoy riding your bike...!!!

 

Thank you for all your help and advice Mike

 

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