Well this has got me a bit confused!! Just changed the engine oil on my 2005 Road King with 8000 miles on it to Redline synthetic20/50. I was expecting the bike to run better on this oil than the HD 360 20/50 that I have always run in it. I took the bike out and gave it a good test and straight away on pulling away I felt that the bike just didn't feel "quite right" if that makes sense. The engine is more vibey and noisier and generally the bike isn't as good to ride as it was before. I have read one or two posts regarding this with synthetic oil and indeed I used to have a BMW R1150RT that felt exactly the same after changing to syn oil. My question is, taken that synthetic oil is obviously more slippy than dino oil, why is it that the bike doesn't SEEM to run as well on it as the dino HD 360. Has anyone any thoughts on this, is maybe that syn oil in aircooled engines isn't right for them - what do you all think ??????

 

What brand of synthetic oil did you use? Is it a pure synthetic or blend? What are your ambient riding conditions? I think sometimes the expectation of how a machine is going to behave after moving to synthetics is a bit higher than reality. All things being equal, you really shouldn't notice any difference in how an engine runs when moving to synthetic oil...

 

In his post he stated Redline 20/50 synthetic. Yes your right, there should have been no real noticable diffrence in how the engine runs other than maybe runing a few degrees cooler.

Take Care,
Bill G

 

The main reason Iswitched to a syn is for the heat reduction.I just switch to Amsoil but cant say the engine sounds much different.I switched for the cooling.
I am also using Redline in the tranny.The tranny is no quiter but the syn is better than dino oil.

 

I am running Redline 20/60 and think the top end is a bit quieter. No obvious difference in running perceived but I swithched FROM Amsoil 20/50 to the slightly heavier Redline. Redline is a group five syn, the best base available from all I've read, most other oils discussed here are type four or Syn 3 which is type three (a blend, semi syn).

I honestly don't know if there is a "muffling" effect with 360 dino but can't
really say there could be any real difference in running, other than a bit cooler and capable of withstanding higher temperatures than dino.

The tranny noise, IF you mean the clunky shifting, is really a function of the clutch adjustment at the basket (eliminate drag by adjusting to the half turn rather than full turn out and adjust the lever cable tighter). It can also mean that the primary is overfilled, causing the clutch to drag.

The tranny noise that a good gear oil like Redline HD shockproof quiets is gear noise and whining from the transmission.

Sometimes I really think we ALL overthink the oil thing.

EZ

 

I also noticed more engine noise with synthetic oil than with dino oil.

On my '06 Ultra, the engine makes less noise with HD 360 20/50 than with Mobil 1, Syn 3 or Amsoil 20/50 synthetic oils.

BUT, what I also have noticed is that:
- the bike seems to run a little cooler with the synthetics than HD 360
-I have far less metal fragments trapped by the drain-plug magnet when using synthetics than with HD 360
- the bike maintains higher oil pressure on hot days with Amsoil or Mobil 1 than with HD 360 or Syn3

Therefore, from what I have seen with thisbike - I plan to continue using synthetic oil.

However, this is my 6th HDand the first bike that I have used synthetic oil in. The other HD's all did great on HD dino oil. I truly believe that any of the quality 20/50 oils will work just fine --- but synthetic oilsdo a little betterin the summerheat.

This is NOT a jab, but really ---- an '05 with 8K miles? Whatdifference in engine life would it make ifthe HD recommended360 20/50 oil was used or some expensive synthetic? Ifthe bike runs better on HD 360, use it

If you just got the bike with 8K on it and are one of those folks thatride 25K miles per year (and more) you may want to be concerned about one oil being slightly better than another, but I would guess that mostHD ownersride less than 5K milesper year, and either find a new hobby after a couple of years or trade bikes. For the majority of riders, HD 360 works great at keeping the engine from rusting as the bike sits in the garage and collects dust - in between trailer rides to rallys.

BTW, I would guess that after riding your '07, the '05 would feel like it "just didn't feel 'quite right'." Could that be the source of your concern?

JMHO

 

I have only noticed a change in engine noise when I drained the syn 3 out and reoplaced it with mobil 1 synthetic. It seems to run smoother but I don't really see that much of a difference in temps.

 

Lots of people notice different levels of noise with different oils. My TC88 was making all kinds of clattering under acceleration with Syn3. I switched to Mobil1Vtwin.......smoother and quieter. I'm going to try some Redline and see how that runs later this season.

 

That might be attributable to break-in. If the HD360 was used first, then followed by a variety of synthetics, the engine has gone through its break-in process and magnet deposits should decrease with time. On mine, I noticed some at the 500-mile change, then less at 1000 and subsequent changes. I didn't switch to synthetic until 2k miles to allow the engine to break-in thoroughly, and deposits have all but disappeared.

IMO that is undoubtedly a sound decision.