Synth or NO synth

[mayfair]

Ok, here's the deal ... In my Sporty I was convinced to try synth oil, and I pretty much immediately noticed that it was running hotter. I could tel not just from the oil temp gauge, but also from the heat coming off of the pipes as well as how the bike ran. I switched back to regular old oil and it was fine.

On my Fatboy, I was again convinced to give it a try. I didn't notice the heating issue this time until I was stuck in some serious traffic. Then it REALLY heated up! I've since switched back to regular old oil, and everything is fine.

Ok, here's the reason why I question going back.

I've mentioned my experiences to several friends, and after getting this "shocked" look and hearing stories of how it's impossible, one guy actually had me thinking. He told me that the synth oil is thinner and the bike WILL tend to run hotter, however it does a MUCH better job of protecting the engine.



So my question boils down to this ... Am I better off running hot and supposedly being better protected, or am I better off running standard oil and never heating up at all?

[Buford445]

I thought Harley Oil was Syn

[mayfair]

You can go with Screamin Eagle (synth), or regular ole 20/50

[Mitch]

Of course you don't want too hot, but hotter is better than too cold. Metal expands. When an engine is cold, the tolerance between the moving parts is not withing spec for optimal performance. The engine wears the most when it is cold, just like with our diesel engines, short trips are what kills them.

So the hotter is the better ticket. I don't know much about bikes and air cooled engines, but I haven't ever heard of a Harley engine falling apart from temperature...

[Kilch123]

I run the Screamin Eagle 20W50 in mine, and haven't had an overheat issue except one time last summer caught in DC Beltway traffic

Synthetic oil will hold up better in hot conditions than Dino oil

[Cumminalong]

I've mentioned my experiences to several friends, and after getting this "shocked" look and hearing stories of how it's impossible, one guy actually had me thinking. He told me that the synth oil is thinner and the bike WILL tend to run hotter, however it does a MUCH better job of protecting the engine.

Donny, if both oils are the same weight, neither should be thinner than the other....that's the whole purpose of the numbering.

The only difference between dino oils and full synthetics should be the base stocks and the companies additive packages.

Otherwise, a 20W50 is a 20W50 is a 20W50.

Otherwise, it wouldn't be a 20W50.

[cntryby]

Of course you don't want too hot, but hotter is better than too cold. Metal expands. When an engine is cold, the tolerance between the moving parts is not withing spec for optimal performance. The engine wears the most when it is cold, just like with our diesel engines, short trips are what kills them.

So the hotter is the better ticket. I don't know much about bikes and air cooled engines, but I haven't ever heard of a Harley engine falling apart from temperature...

Careful... thats mostly true, but there is some gray area.

Cold engine wear comes right at start up, before oil gets pumped throughout the engine. Other things happen too, but most of all an engine just doesn't run as efficient when cold. This can cause some deposits & build up (sludge)  over time. If it runs really cold it may not be able to displace the condensations and cause corrosion.

Hot, beyond normal, will cause tighter fitting components that can cause wear due to the lack of ability of lubrication penetrating the gaps. This can seize up an engine in extreme cases. Of course, synthetics are capable of lubricating better under these conditions than dyno. Still, the tighter the fit during friction, the more wear will happen.

I would much rather run a little cool than hot. HEAT is an engines enemy. (beyond normal operating parameters.)

[Mitch]

Of course you don't want too hot, but hotter is better than too cold. Metal expands. When an engine is cold, the tolerance between the moving parts is not withing spec for optimal performance. The engine wears the most when it is cold, just like with our diesel engines, short trips are what kills them.

So the hotter is the better ticket. I don't know much about bikes and air cooled engines, but I haven't ever heard of a Harley engine falling apart from temperature...

Careful... thats mostly true, but there is some gray area.

Cold engine wear comes right at start up, before oil gets pumped throughout the engine. Other things happen too, but most of all an engine just doesn't run as efficient when cold. This can cause some deposits & build up (sludge)  over time. If it runs really cold it may not be able to displace the condensations and cause corrosion.

Hot, beyond normal, will cause tighter fitting components that can cause wear due to the lack of ability of lubrication penetrating the gaps. This can seize up an engine in extreme cases. Of course, synthetics are capable of lubricating better under these conditions than dyno. Still, the tighter the fit during friction, the more wear will happen.

I would much rather run a little cool than hot. HEAT is an engines enemy. (beyond normal operating parameters.)

I think you may have misunderstood that a little. I didn't mean overheating an engine is better, I said running a little hotter is better opposed to cold. There is no lack of lubrication at operating temperature, which is the reason why there are clearance specs when engines are built.  I don't disagree that engines don't wear due to heat, that is a given, metal gets brittle at certain temps. What I was saying is a cold engine is worse than a slightly warmer than normal engine.

I forgot what this thread was about now..... 

[mayfair]

I've mentioned my experiences to several friends, and after getting this "shocked" look and hearing stories of how it's impossible, one guy actually had me thinking. He told me that the synth oil is thinner and the bike WILL tend to run hotter, however it does a MUCH better job of protecting the engine.

Donny, if both oils are the same weight, neither should be thinner than the other....that's the whole purpose of the numbering.

The only difference between dino oils and full synthetics should be the base stocks and the companies additive packages.

Otherwise, a 20W50 is a 20W50 is a 20W50.

Otherwise, it wouldn't be a 20W50.

Both are 20w50, however for some reason when running the synth 20w50, the bike gets REAL hot (like Kilch mentioned) when it's not really moving. I can't explain why, but it's happened in both of my bikes.

[cntryby]

I think you may have misunderstood that a little. I didn't mean overheating an engine is better, I said running a little hotter is better opposed to cold. There is no lack of lubrication at operating temperature, which is the reason why there are clearance specs when engines are built.  I don't disagree that engines don't wear due to heat, that is a given, metal gets brittle at certain temps. What I was saying is a cold engine is worse than a slightly warmer than normal engine.

I forgot what this thread was about now..... 

Yep, I'd agree with that... especially over a long period of time.

[Buzzy]

Donny I would invest in a cheap infra red temp gauge.
I don't see how dino or synth could have any affect on heat. Heat is cause by friction and if your bike did indeed get hotter, then the oil had to be ineffective at lubricating the moving parts. I don't see how this is possible as even the cheapest crap oil will do a good job of lubing in the short term.

I am wondering if your mind got the best of you and because you were worried about it, you payed closer attention to it and noticed the heat?
What I would do it take temp readings all over the bike, ride it, idle it and check again. Put the synth in it and do the same thing, check temps all over the bike under the exact same conditions you did with the dino temp reading. Make sure the ambient temperature outside is the same for both test including humidity.

I would almost put money on it that you will find very similar temps with both oils. "Feeling Hot" is a relative term and is subject to ones perception of "Hot" at a given time.

[mayfair]

Donny I would invest in a cheap infra red temp gauge.
I don't see how dino or synth could have any affect on heat. Heat is cause by friction and if your bike did indeed get hotter, then the oil had to be ineffective at lubricating the moving parts. I don't see how this is possible as even the cheapest crap oil will do a good job of lubing in the short term.

I am wondering if your mind got the best of you and because you were worried about it, you payed closer attention to it and noticed the heat?
What I would do it take temp readings all over the bike, ride it, idle it and check again. Put the synth in it and do the same thing, check temps all over the bike under the exact same conditions you did with the dino temp reading. Make sure the ambient temperature outside is the same for both test including humidity.

I would almost put money on it that you will find very similar temps with both oils. "Feeling Hot" is a relative term and is subject to ones perception of "Hot" at a given time.

Thanks for replying Buzz, I was kinda hoping that you would since I know that you ride as well. 

As far as the whole temp thing, I have a gauge right in my oil tank that I can easily see while riding (or sitting still). Reading this gauge is where I got my "running hot" thing from, not just from the heat coming off of my motor and up my ass! Also, as Kilch mentioned, my motor has actually cut off due to the heat, whereas it's never happened using regular ole oil. I don't need a meter or gauge in these situations to tell me that my motor is runnin hot!

 Keep in mind that the motor heats up while sitting in traffic (traffic jam ... Bike Weeks ... etc) not while actually riding.

I'm getting ready to get the bike ready for the season, and doing an oil change is part of the part of getting it ready. I'm really curious as to what you guys think.

Thanks!

[kenz]

Donny, are you using the Harley synthetic or another brand? Reason I mention this, and this is how I remember it being told to me by my Harley dealer, is that the Harley oil (I only used the 20w50 dino oil) is formulated for the air cooled engine. The oil not only lubricates, but wicks heat away. The oil is designed to help disperse engine heat. So maybe with the synthetic oil not being able to absorb/wick away the heat, the engine holds more of it in until it gets to hot.

[mayfair]

Donny, are you using the Harley synthetic or another brand? Reason I mention this, and this is how I remember it being told to me by my Harley dealer, is that the Harley oil (I only used the 20w50 dino oil) is formulated for the air cooled engine. The oil not only lubricates, but wicks heat away. The oil is designed to help disperse engine heat. So maybe with the synthetic oil not being able to absorb/wick away the heat, the engine holds more of it in until it gets to hot.

That make sense, and it sounds like exactly what is happening.
I don't know if Harley actually makes a synth oil, however they sell (and the dealer recommended) a synth oil called Screamin Eagle. That is the synth that I was referring to.

[mayfair]

As Spence would say .... HOLY FLIPPIN CRAP !!!!!!

I think I just answered my own question as to what I'll be using this year!

Tonight, I decided to drain the oil from my bike before getting the new stuff Thursday. The oil filter is a messy PITA, so I poke a hole in the side of it and let it bleed out for a day or so before removing it. Otherwise, it gets everywhere.

So tonight, I removed the oil drain plug, and honest to God, DROPS of oil came out!

I was stressin! I started second guessing if the plug that I removed was indeed the oil drain plug, so I poured some fresh oil in and sure enough, it bled out.

YIKES!!!

I then poked a hole in the side of my oil filter, and again, not even a dixie cups worth!

Does oil evaporate?

It's an 03 with 21K on it. I really only rode it a handfull of times last year, not much or far at all. The bike never smoked or ran hot, so where did it go? It certainly didn't leak out?



Since I never had this happen before using synth, unless you guy's can give me a rational explanation as to where my oil went, I guess I'll be switching back. This is the scariest and weirdest thing that has ever happened to me as far as the bike goes. Thank God I decided to change the oil before firing it up this season!