[DanDiver]

I met someone today who told me that in his Harley, he switched from regular oil to a particular brand of synthetic and his engine ran almost 10 degrees cooler. He claims to be a skeptical engineer, does not sell oil and I'm sure his conclusion is anecdotal. Has anyone else experienced this?

 

[SilverBuffalo]

synthetic oil absorbs heat less than "regular" oil,
so there might be "some" thruth to what he says.

I swear, my bike runs better when I wash it (once or twice a year)

all oil is essentially "microscopic ball bearings"
think of synthetic as even smaller ball bearings.

Whether the benefits justify the cost is subjective,
you'll have to decide that one for yourself,

I use Mobil1 and extend my oil change intervals to "offset" the increased cost.

 

[fpmlt]

I use synthetic in all my rigs, one being a Harley. I went out with a heat gun and an oil dipstick/temp gauge. Ran the same route same speed etc., as "scientifically" as I could. Recorded a 14 degree drop in oil temps, and that was running while the ambient temps were higher than the test using dino oil. I could give you a long winded story about using syn hyd fluids where I work, but short story, motors lasting 4X longer now, machine runs cooler and faster. I also have UOA that shows, so far, my Harley engine wear reduced unbelievably. I would never go back, but that's just me.

 

[DanDiver]

thanks.... that was what I was looking for. Guess after 36,000 miles it's time to switch to synthetic. I'll still change all three every 6,000 miles, but in Florida in the summer, the engine does seem to get hot.

 

[yechave]

I run Mobile 1 in everything I own, except, our 99LT. We were told with 48k miles, it was too risky to now change to synth. The oil removes the paraffin from the seals having used the dino oil, which then leads to the clutch going. It was not worth the risk for us to do so.

Were it not for the dry clutch, I would not hesitate to switch.

I had 35k on my Ford when I switched, and did so with the engine, trans, rear. It ran significantly better, shifted better and is much easier to start in cold Pa winters.

I decided to do so after using the synth in our snowblower. The first two years I could not start the blower without the electric starter. Once I switched to synth, I have not used the starter since.

I am sure it is the way to go!

 

[DanDiver]

I run Mobile 1 in everything I own, except, our 99LT. We were told with 48k miles, it was too risky to now change to synth. The oil removes the paraffin from the seals having used the dino oil, which then leads to the clutch going. It was not worth the risk for us to do so.
!

Guess then I better wait for the jury's decision. I was going to switch and I have a few 1,000 miles to decide..... so...... guess the decision is to wait.. thanks

 

[cfell]

10 degrees shy of "China Syndrome".. wow...

In my HD, the greatest reduction in temperature was due to many factors... Temperature and Relative Humidity (wet bulb), seasonal Fuel choice, load, winds, roads, etc.

The greatest heat problem was during 'breakin'... which for many HD riders takes several years.

I recall that my Sportster never ran better or cooler than when I ran 120 octane Aviation fuel... and, mixing that fuel with the dino-oil generated an intoxicating perfume...

edit..
PS... I run synthetic in all my motors after breakin.. and have had zero engine failures..

 

[fpmlt]

You forgot to mention air/fuel mixture. Putting on a powercommander and richening the mixture slightly will also drop temps. While I agree with all you stated, remember that I ran my little test on the same tank of fuel, same day, same route, same speed etc., and got good results on my bike.
Also consider that this oil temp problem is probably more critical in an air cooled motor than liquid. But, then again, reduced heat likely relates to less friction, thus better wear patterns. That's my story, and I'm sticking to it!!!
It's always a huge debate, and a guy's gotta do what gives the best "feel good" effect.

 

[jarhead354]

Is it better (safer) to switch to synthetic earlier on than later? For instance, I just bought a used '03 with 19k miles and was considering switching to synthetic but I'm not convinced it's safe to do so.

Thanks,
Frank Carroll

 

[cfell]

Frank...
Should be no problem changing.

However, there have been folks who experienced "seal" failure after changing oil types... and blame the oil for it... but there are some who have run exclusively dino or synth who have had failures..... and some had no failure... but worry about it anyway.

If you plan to keep the bike, do what gives you the confidence and just fix it if it breaks.

Semper Fi...

 

[JATownsend]

I do a lot of work for General Motors. Around 1996, I was supporting a group of engineers working on advanced vehicles. They ALL rode HDs, and they hated the fact that HD stipulated that ONLY HD oil be used in their bikes.

This group decided to take HD to task. They ALL installed recording temp gauges on their bikes. Then they each ran a 1000 mile loop with HD...Then a 1000 mile loop with Mobil One.

The M1 run recorded much lower oil temps. Much lower. They then joined the main group, who was trying to FORCE HD to allow other lubes to be used.

They won! And, changed HDs position on the matter. Period.

Now, what has this got to do with our LIQUID COOLED LTs???

 

[LAF]

My Road Glide ran 13 degrees cooler with Synth oil. This by a heat gun and the oil temp gauge.

I use it in everything I run.

Here in PA I use 20-50 summers and 10-40 winters.

Way too much data on the benefits of true PAO oil.

The biggest thing is cost. If you don't loose the traditional mentality of our Dads on changing oil every 2500-3000.

The thing is at 6000 miles you can just change the filter and top it off
(Except on this bike) run it to 12,000 and drop the oil and new filter. This is where the benefit and a break-even cost are for a PAO Synthetic.

Well not all the benefit, it will without a doubt reduce oil temps, does not break down or sheer until a much higher temp then dino, and is quicker to flow on cold starts because of its molecular structure.

Now on our bikes I have used it in the FD and Transmission since 600 miles. I change all at every 3000 mile. I wanted to get 15,000 on before I switched. That on my Service Manager's advice, I would have done it at 600 otherwise.

So another couple of 1000 and I will switch over and use the brand of oil I use with its matching filter, and start going the 6000 with no worries, well will continue to do the FD every 3000 to keep an eye on it.

 

[RealWing]

I changed the engine to synthetic at 20,000 Km (13,000miles), the Tranny at 1000 Km and the rear drive at 10,000 Km and have been doing analysis on the oils since day 1.

 

[leiboshi]

synthetic oil absorbs heat less than "regular" oil,
so there might be "some" thruth to what he says.

I swear, my bike runs better when I wash it (once or twice a year)

all oil is essentially "microscopic ball bearings"
think of synthetic as even smaller ball bearings.

Actually all those "bearing balls" in synthetic oil are similar size comparing to mineral oil, where particle size variates. This makes synthetic oil charasteristics better, less friction, less viscosity variation between different temperatures.

I have been only synthetic oil in all my vehicles already close to twenty years. Difference is remarcable in winter time, but I have never recognized any temperature difference in running summer time. Maybe, because I have not had any aircooled vehicle since 1978! Watercooling system is keeping motor in certain temperature regardless what kind of oil is inside the motor.

Tranny (if not using same oil with motor) and rear gear are then different issues. They might run in lower temperature with synthetic oil. I have synthetic oil in rear gear as well.

Only problem coming with synthetic oil according to my knowledge is clutch slipping, when having wet clutch (not in LT). Well I have synthetic oil also in my K1200S but I have not had any problems so far.

Regards
Leiboshi

 

[DanDiver]

Guess then the question, Who has switched from regular oil to synthetic after 25-35,000 miles and did you have any problems associated with the switch?

My TROUBLE FREE K1200LT is an 02 if that might make a difference.

 

[zippy_gg]

Guess then the question, Who has switched from regular oil to synthetic after 25-35,000 miles and did you have any problems associated with the switch?

My TROUBLE FREE K1200LT is an 02 if that might make a difference.

I did that on my 03 bought with 19K miles. I switched to synthetic at about 23K miles an kept the bike until 47k, at which time I bought my 05.
Never had an issue after the switch.

 

[rkimmel2]

Switched my 99 at 21000 miles. No problems.

 

[Caveno]

I switched my 02 LT to synthetic at 30k miles, no problems.