I know there have been thousands of discussions about this subject, but I was talking to my good buddy (small engine brainiac) today regarding synthetic additives and my 99 Wide Glide.....
He says that if you are a fanatic about changing your oil and old-school enough to change it every 2500 to 3000 miles on the dot (which I have always done with all my cars and bikes), regular oil is fine and synthetic is not a necessity. I also remember reading a few posts regarding the engines running a little hotter when using synthetic? Is this true?
He did, however, say thatin the primary and tranny case (since there is substantially less heat in those galleys) he believes wholeheartedly in using synthetic oilsfor those items.
Can anyone here tell me if theystill use conventional oil for the engine itself, but run synthetic in the tranny and primary?
Just trying to come up with a system I can stick to with this bike....I bought it usedwithlow miles and want to make her last with as little wear as possible......
Thanks in advance.

 

This oil thinggy is a never ending story and I guess this one will go on and on or someone will divert the attention so readers check out older posts where everything has been beaten to death.

One thing though, after you have done your running in, then synthetics are more than fine since they lubricate better and withstand higher temperatures than the dyno oils (even though both come from the same source). Synthetic oil if anything, with keep your engine cooler, will need less oil changes and will protect your engine better for it is a better lubricant than the mineral oil.

Having said that, on my previous mount, a V-Max, the synthetic was a killer. As you accelerated it was so "slippery" that it would run back to the rear end of the engine, leave the oil pump without oil and if you were not careful you could end-up damaging the big-ends. That is not our case here as far as I know.

 

There are thousands of opinions on this but since i get to be one of the first to respond to this I'll do so.
I run synthetic in the engine because of its ability to handle high temperatures without breaking down. I think that my bike may run cooler with syn but that is subjective and it would be only a few degrees. If i am in hot weather and running hard though the syn oil provides some cushion on the upper level of the running temps before it starts to break down and fail over dino oil. I like the way syn oil feels in the bike and believe it gives me some increased performance at the upper rpm range. Again this is subjective but that's the way the motor feels. I use Rev Tec RedLine

I will only use conventional heavy weight non-syn gear lube in the trans/primary. There is no substitute for the viscosity provided by these lubes in the syn lube world. The gear shearing in the tranny creates is a harsh environment for lube and the most reputable people i have found in my research recommend the heavyweight standard lubes.

good luck with your decision. The good thing is, with regular changes of whatever fluid you choose your bike will last a long long time.

 

Iuse HD 20W50 in the engine and HD Formula + in the tranny and the primary. I change the all 3 oils as the manual says every 5,000 miles. No problems yet. At 5,000 miles the engine oil doesn't really look that dirty, but I am sure that it has some thermal break-down. I think that I read somewhere that they(HD) have increased the oil change intervals for the tranny and primary. I currently have just under 13,000 miles on my bike, the oils were changed at 1,000 miles, 5,000 miles and 10,000 miles.

IMHO every 2,500 or 3,000 is overkill. I also think that Synthetic oil is also overkill and due its viscosity and it being thinner than the regular oil it would create a thinner lubricating bearrier between working surfaces which could be the result of the bearing failures, but what do I know, this is just what I think.

 

To me sythetics are the way to go.

All oils have additive packages to enhance the qualitys of the oil, the the sythetics have a lower friction coeffent + additives to allow for longer life on engine parts, thus the engine runs cooler and makes more power.

I think of it as cheap insurance on the high dollar parts I bought to go fast.

but just having regular consistant oil changes at the recomended intervals speaks volumes in itself!