Synthetic oil: anyone run synthetic 50-60 weight oil

[53rigidrider]

Anyone run synthetic 50-60 weight oil? I've got alot of references about it, but haven't tried it yet. The main point I'm looking at is working parts lubrication in the heads. Any experience with this?

Thanks in advance! ;D

[shaker]

i started using the new mobile v- twin syn 20-50 , was using hd 60 , had a small head gasket leak it stopped , when i went to the 20-50 it was on the return side , guess it can flow better with the thiner oil, bike runs cooler with the syn also, but it is high $ oil if the bike used a lot of oil would prob, go back to regular oil, i change the filter every 1000 mi, and filter and oil every 2000 mi so it's not to bad..

[sleeper]

I like the Synthetic 20-50 Mobil 1 for bikes or
Amsoil Synthetic.............Both "First Rate"
I figure the oil is the least $ expensive thing in the bike. Make it the best!!!

Jack got me hooked on the Amsoil oil filters.

I have noticed lil' cooler running also., using synthetics Which has to be a Good thing...
I even use it in my Air Compressor..

[chopper]

Now you get me confused, cant say i know that much about oil but i've always been told to stay away from synthetic oil in old motors. Straight 50 oil is what i 've always use in motor and gearbox for my Pan, maybe that's totally wrong ??? and i'm looking forward to learn more in the subject.

As you say Billy "you learn something new every day"

Rikard.....

[Jack_Hester]

Rikard -

I've been running synthetics for so long, I have to stop and really think of when I first started. I have it in my 59 Pan and my 76 Shovel. When my WLA is finished (hopefully by Christmas) it will have synthetic in it. I used to do breakins with dino oil, but have decided that this one will start with synthetic. I've done it before. I burned the rings up in my 76, years ago, crawling through a traffic jam on a bridge over the Mississippi. Had synthetic in the tank when I put the new rings in. Never switched. Synthetic oil in older machines has never been a problem for me. There are different grades of so-called '100%' synthetics. Mobil 1 and Amsoil are two of the highest grades. I don't bother to try to find out which of the others are of what grade. These two are easy for me to get, so they are my staple. The Mobil 1 and Amsoil spin-on filters are killer high efficiency filters. Too bad they don't make the cartridges for Pans and Shovels. Amsoil does make spin-on replacements. If you can find OEM H-D filters for the Pans and Shovels, they are high efficiency. I was told by an Amsoil technician that they were some of the best made. No one can vouch for the aftermarket fiber jobs, though.

The high grade synthetics are unique in that they cling to metal, and do not entirely run off, as dino oil does. If you want to paint something that has had prolonged exposure to synthetic oil, you had better soak it in solvent for a while. And, wash in soapy water so hot that you can't hardly keep your hands in it. Then, maybe the paint will stay on. Maybe.

I'll get off this soap box, now. I can get wound up on synthetics. Have a good one.

Jack

[sleeper]

I agree with Synthetics ability to "Cling" to parts.
ie: My yard tractor is on synthetics, But when it was brand new, I broke it in on fossil oil. & it would sit there a week or 2, when I checked the oil on fossil, it was down at correct level.
On Synthetics, same time sitting for my tractor & go to check oil [always] before starting. Oil is still splashed way up the dip-stick from last use, & have to wipe off & re-check.
That's Clinging!! If it's doing that on my dip-stick, I am sure it is doing the same thru-out the motor. Helping to avoid "Dry starts".... I'm sold & have been for long time.

[chopper]

Thanks Jack and Billy, maybe i have to "dig deeper" in the subject, what you say about the fossil oil on the stick is true. But what about the synthetic oil gets thinner when hot, like you all know old Harley motors have a way of "marking their spots" and if the oil is thin it should have a easier way out (leak), but maybe it's just a myth that the fossil oil stays thicker when hot ??? Huh it's not easy to put my thoughts on print in English but i think you know what i'm getting at.

Rikard.

[Jack_Hester]

Rikard -

Your English is fine. Oil's ability to cling to parts and resist shearing are the biggest issues. Synthetics do not look like syrup, when poured from the bottle, like dino oils do. But, dino oils actually get very thin as they get hotter. And, start breaking down above 300+ degF. Synthetics have to exceed 600+ degF, before you need to be concerned. Engines just don't reach the temperatures to break down synthetics, in the crankcase. I have personally witnessed crankcase temperatures exceeding 300 degF. I used to build automotive engines on the side, and had an engine stand where I could run them. I monitored oil temperature along with a lot of other points. When an auto engine is warm to where the water temperature is at the thermostat setting, the oil temperature is over 200 degF. Rev the engine to a couple of thousand rpms, and the oil temp climbed to just shy of 300 degF. Load it up just a little and it goes above and never comes under 300, until the engine has run at an idle for about 30 minutes. This is on water-cooled engines. And, of course, much larger engine. But, heat is heat. Get your air cooled engine warmed up and loaded, and you have oil that is much hotter than a water-cooled engine. Above 300, dino oil will not cling. Synthetic never lets go. My theory with leaks is that if it does with synthetics, it was already waiting to happen. Fix the leak and keep the synthetic. I have no leaking issues from synthetics on all my equipment. Sorry for the soap box, again. I'm off.

Jack

[53rigidrider]

Manoman, it's great to be able to call on all this experience without having to fly all over the internet to find it!
I'm running Royal Purple 50 wt in the '53, and hope it helps lube my heads more.
A guy with a '58 swears by it after cracking a case and riding 200 miles for help. His internals were flawless when they yanked the cases apart.
I'll know after my next 500 miles.

Thanks to all for the help!