Take it from a guy with 45 years experience as an aircraft mechanic...Dont`t bother with aviation oil, it isn`t what your motorcycle engine needs, it`s what an airplane engine needs.

Just because it`s an aviation oil does not mean it is better.

 

i agree with mr. dan for the most part
i do use turbine oil in my compressors
and i know people that use av oil in their cars with ill effects. the no. 1 issue was with seal compatibility.
the two engines operate in diff bands unless you are a stunt pilot. av oil is mostly for cleanliness and not about hours.
sticking with mfg recommendations usually works best.
to be honest, does hd require a 50wt???
my 1974 ch has seen everything from 30wt to 90wt, i shy away from multi weight oils of old because of government report, use what was at hand at the moment. a rebuild due to frame restoration (bird in hand) revealed neglectable lower wear and only a .010 over bore to straighten up the cyls(at 175k miles). reason is that back when, oil changed as an over kill at 2k miles.

 

Reading some posts in here are just laughable, thinking they know all about oil better then the manufacturer of a product. One thing for sure, last thing on earth I would want to do is buy a car, truck, boat, piston aircraft or motorcycle from some of these people who use oil not recommended by the manufacturer because they "know" better. Dont get me wrong, most bikes dont run the mileage of cars, truck, boats and "planes" so chances are it really doesnt matter but I just dont get it, why on earth do people choose oils that are not in spec with the engine maker>?
They base their decisions on marketing hype, incorrect assumptions and worst of all, recommendations in a motorcycle forum. )
As far as some of the incorrect assumptions, people believe the hype that more additives are better, completely wrong, why does one think adding extra zinc the cheapest metal on planet earth to oil, which only displaces the best knitwear additive of all, the actually oil, is better for an engine? WhY? Because oil forums but its completely wrong, too many additives in oil create and add to piston deposits, do you know what piston deposits do? they wear out your cylinder walls! *L* But forget all that, everyone knows better then the engine makers right?

Here is 5 UOAs on oil run in my Road King, three of the last using Mystic JT8 15/50 HDEO rated CH4+ and better as recommended by Harley (if their oil not available but whatever)
Read my UOA in the link below -
https://www.bobistheoilguy.com/forum...87/type/thread

 

READ my post above this one ^^^
https://www.bobistheoilguy.com/forum...87/type/thread


For those who dont care to read the link above, here you go;

 

then why do you run 15W50 when the owners manuals state to run 20W50, all other alternatives are just that, not the preferred spec by the manufacturer...I mean HD doesn't even offer a 15W50..I'm sure it's relatively small and inconsequential but still just a little contradictory anyway

 

I Changed my own engine oil today, 2004 FXSTI
I used Mobil 1 Delvac 1300 Super 15w-40 heavy duty diesel oil, because I happened to have 3 quarts of it. I figured it would be ok, so am I safe? Bike has about 17K miles

 

did it need changing so bad that it couldn't wait to ask that question ahead of doing it? LOL...and really...about a 17 year old bike with 17,000 miles...not sure it matters

 

Do you have anything useful for me or just gonna troll?

 

It'll be just fine. Been running Rotella in my Suzukis for years with no problems.

 

Thanks!