I recently picked up a near-mint 94' Classic with 14K miles on her, and need some advice. Is it a good, or bad, idea to switch the bike over to synthetic oil at this point? If it gets switched over, what are the consequences, and, what would be a good oil to use in either situation. The one-owner scoot has used HD oil from day one. Thanx much to all of you, in advance, for helpin' me out here. Mack

 

Alot of people run syn and a lot run dino oil.Its up to you.
I would say just use the HD 360 and change the oil/filter every 2500.

 

Well wouldn't want to be off topic now...

 

[quote]ORIGINAL: Richard






Went back to HD Trans/Primary and 20/50 HD oil at 2500..
The Synthtic oil made things too noisey[/size]

And the oil changes were less expensive..


Totaly off topic bike wise at least, but I am running a total syn oil in my 4cyl 4Runner 30000 miles on a new motor... it is noisy, even more so than what I am used to,
As for the Ultra, I am curently running Amsoil 70-90 in the transmission for the second time around and not sold on it 100% as it shifts nice for the first 2500 miles and gets a bit sloppy after that, nothing scientific , just seat of pants and feel from the heel shift, so the jurry is still out ...
My .02 worth, run the traditional oils as per your owners/sservice manual and enjoy the ride, cause it aint worth fretting about.
Or as most guys and gals do here try it once or twice and see for yourself!
Cheers,
Rob

 

Synthetic oil doesn't break down from heat like petrolium based oil does. That's important in a air cooled engine idling in traffic on a hot summer day. I change mine every 2500 miles. I run synthetic in the trans and primary also. I change them every other oil change. My dealer says that's overkill. Maybe it is. To me it's piece of mind. He says synthetic lasts a lot longer than petrolium based oil. That's true, but dirt, metal shavings and contaminants still get in the oil no matter what you run.

The bottom line is; no matter which you choose change it reguarly and it should last a long time.

 

I personally prefer RedLine 20W-50 synthetic in the engine due to its heat resistant properties and better friction(less) properties. However, I personally think it's a mistake to use synthetic oil in the primary. Our Harleys use a wet clutch that depends upon friction between the plates to make the bike go. Synthetic oil is considerably slipperyer (if that's a word) than standard dino oils - so, I use good ol' Pennzoil 20W-50 in the primary to lube the chain and to keep the clutch cool. I use RedLine Heavy Shockproof oil in the tranny - change the tranny once per year and the other oils every 5k.

 

wax-based vs oil-based is an argument that has valid points on both sides. If you ride in heavy traffic in mid-summer, the benefits outweigh some of the disadvantages. Perceived or real. Some local wrenches say that full synth don't allow enough friction for the cam bearings and they develop flat spots. base weight (viscosity) if the same, won't have any difference in mechanical noise. Any engine with an aluminum alloy casting for a cylinder head should be broken in with petroleum-based, followed by one more oil change before going full-synth. The molecular breakdown during normal combustion is not unlike "seasoning" a cast-iron skillet. Sealing the pores of what essentially is a sponge made of metal, eliminates possibility of seepage. It sounds like alchemy, but most major auto manufacturers have bulletins regarding this method of break-in.

 

Good points and I concur - although the techs at HD send most if not all of their bikes through with SYN3 now.

 

rmack,

Synthetic is superior to petroleum based oil for the reasons listed above. If the bike were mine I would run Harley Syn3 (I do) or Mobil 1 V Twin.
That said, when you swich to synthetic you may find some oil leaks, more than likely the base gasgets (rear cyl left rear is most likely) or the rocker boxes. The syn oil just finds it's way out.

DC

 

Waste of money