Ooops. I guess it's my turn ...

[Cipher]

IIRC the synth does not cause oil leaks but can find leaks in an engine with marginal seals.
Sad how a silly myth can persist.

[Nessism]

Definitely don't want to start a oil debate. But since it's kind of already started. I would like to ask Steve a question, with all do respect. Why do you use the synthetic motor oil in your motorcycles? What is the big advantage in running synthetic motor oil in our Suzuki engines... In my experience with synthetic motor oil, it always caused a leak within short time. The last experience, was with my BMW. I switched to Amsoil synthetic motorcycle oil. 1000 miles later the base gasket started leaking... With my oil burners, I change the oil in the fall (end of riding season) and keep them topped off during the summer. They always has clean oil in them.☺

I use synthetic oil in my bikes and car. Zero oil leaks. Maybe because I maintain my equipment. In the case of my car I use synthetic because I only have to change the oil once per year that way. For my bikes I like synthetic oil because of it's superior high temperature stability. My 1000S's oil temperature gets up into the 300F range and I want the most protection possible.

[Steve]

Why do you use the synthetic motor oil in your motorcycles? What is the big advantage in running synthetic motor oil in our Suzuki engines...

Nessism pretty much summed it up, it's more heat-tolerant and more consistent. The additive package is also more likely to be consistent, because they are not relying on any inherent quality of the oil. They start with a known 'base' and add what they want, in the quantities that they want, to get the final product.

As to "synthetic will make your engine leak": hogwash. If your engine leaks with synthetic, it would also leak with 'regular' (dino) oil, if the dino oil hadn't clogged up trying to get through the leak. Synthetic oils typically have stronger detergent packages in them, so they tend to wash away at the clogged pores, uncovering any leaks that have been there all along, but clogged.

I gave you the history of most of my GSes, for the most part, they are oil tight. My wife's clutch release arm leaks a bit. I have a new seal for it, just haven't bothered to change it yet. Synthetic oil did not make it leak, 68,000+ miles did. I have a similar leak on my Wing. The seal and bushing for the shifter shaft have worn a bit, allowing a bit of oil to escape. Oil caused? Nope, just some extra strain caused by improper linkage on a heel/toe shifter. I need to adjust the linkage to get it right, then change the bushing.

One other small advantage of synthetic oil is the 5w- viscosity. The thinner oil will flow quicker through the small oil passages, giving better lubrication on a cold start-up.

I do leave it in there just a little bit longer than some people do, but maybe not enough to offset the extra cost, so it does cost me a penny or two per mile more than dino oil for the duration of an oil change, but that is a small price to pay for what I feel is peace of mind.

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[Steve]

OK, no diagnosis results tonight.

I was headed out to the shop, got a text message from another GSer who was on his way with a broken clutch cable. I told him I had some cables, but did not know what all I had, come on over. While waiting for him, ANOTHER GSer stopped by, had a dead battery just down the street. Diagnosed that one to a dead stator, which he will order.

Bottom line, two extra bikes in the shop right now. It looks like they are BREEDING.



Just got back from taking one of them home, it's bedtime now.


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[Buffalo Bill]

My 92 GSXR1100 engine developed a slipping clutch. The RPM readings I got at 55MPH and 70MPH were higher than what the Gearing Commander indicated they should be. It was plainly slipping under hard acceleration in 2nd and 3rd.
I was looking at replacing the springs and friction plates when I read a warning in the description of the EBC Kevlar friction plates; “Not for use with full synthetic oil”. So I drained the Mobile 1 synthetic out, and added Valvoline Motorcycle oil.
The clutch is gripping very well now, I detect no slipping anytime and the RPM readings match what the Gearing Commander indicates they should be at select speeds in 5th.
This is a salvage engine, I have no idea what kind of plates the PO put in there.

[Cipher]

There is politics and religion but these never come close to oil in terms of controversy. No one can keep still in the presence of an oil thread.
Aside from being of a stellar slipperiness what changes in hydrodynamics occur in synth oil to make it such a clutch destroyer?

Or were your steels and fibres already on the way out?

[storm 64]

""Synthetic oils typically have stronger detergent packages in them, so they tend to wash away at the clogged pores uncovering any leaks that have been there all along but clogged""

That's all I need to hear to convince me to stay with non synthetic motor oil. I don't want the stronger detergents washing away at my pores causing leaks. 👍

[TxGSrider]

""Synthetic oils typically have stronger detergent packages in them, so they tend to wash away at the clogged pores uncovering any leaks that have been there all along but clogged""

That's all I need to hear to convince me to stay with non synthetic motor oil. I don't want the stronger detergents washing away at my pores causing leaks. 

I guess I'll step into this because it sounds like a fun topic.
Going with what we "may" have learned here about synthetics, along with a couple previous posts, lets take it to its logical conclusions... It may have flow easier so it may find leaks easier. It may have more detergents so it may clean away small pore leaks. It is more resistant to heat breakdown (and thus turning to carbon particles), so the little pieces of carbon that might ordinarily gather in small places and block leaks are less likely to form and more likely to wash away. So all of this points out one thing to me... you've got a leaky gasket that needs to be changed. lol!
I mean lets face it, if it is just some pieces of crud floating around a motor keeping a gasket from leaking, then its time to fix the gasket.. and change the oil. lol!

[storm 64]

But my motorcycles don't have any leaks, so what gaskets do I need to change? I'm not going to switch to synthetic motor oil with stronger detergents to find out... My motorcycles are loving life with regular dino Rotella and annual oil changes...

[Cipher]

annual oil change? dear lord you cannot be driving much. Higher mileage change intervals are nice but an MC really does not get much chance to benefit from truly bitter cold starts. I remember years ago when I first used synth in the 80s. -30celsius is hard on starters. I left my oil jug in the truck overnight and in the am was amazed to find the liquid was almost water like in spite of the freezing temps. Dino would have run like molasses.

What is replacing a few seals compared to a drive train or gears or pistons and rings though?

[Wingsconsin]

On my Goldwing I have had some oil testing done -
I sent samples off to Blackstone Labs to get the reports.
One test was on Synthetic oil with about 4000 miles on it. (Came back near perfect-they recommended a longer run)
The next test was 6800 miles (Came back as all good still but ready to be changed soonish)
Now that is a liquid cooled engine so the extremes are less - but full synthetic for longer runs is a good idea in my opinion.

STEVE -- Yes my experience also indicates that synthetic with better flow properties will REVEAL a leak sooner than Dino oil (detergents also?)
But the leak was already there...

[storm 64]

But my motorcycles don't have any leaks, so what gaskets do I need to change? I'm not going to switch to synthetic motor oil with stronger detergents to find out... My motorcycles are loving life with regular dino Rotella and annual oil changes...

Cricket Cricket...

[Steve]

Cricket Cricket...

Huh? Not following you on that one, Norm.

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[Nessism]

Huh? Not following you on that one, Norm.

.

He's just being a jerk. Dismiss.

[ddaniels]

I read a very long article years ago on synthetic oil vs. Dino, and for some reason, the one thing I remember is that, synthetic oil molecules are all the same size, which is kinda small. Dino oil, however has a variety of molecule sizes. What this meant to the guy writing the article is that since synthetic molecules are all the same smallish size, they flow better...and are able to make their way through potential leak spots, where Dino oil may not.