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Synthetic oil in a triple?

16K views 90 replies 32 participants last post by  loxx101 
#1 ·
Since the bikes use a dry clutch, can I run sythetic oil (an automotive synthetic like Mobil 1) in the crankcase for longer life? I know synthetic would be too slippery for bikes with wet clutches.
 
#36 ·
Running decent quality oil in any motor is definitely the best insurance policy you'll ever buy. I was a "Cazzy R" racer back when, and if anybody wants to argue about R's lubrication qualities, you must have a screw loose!! It does however leave a lot more internal cylinder deposits than any Synthetic oils, and that's important on 2 strokes. This requires a lot more diligence in regular maintenance - a true fact.
Most of my racing experiences have been with either motors with separate primary drives, or dry clutches, where I would use a different oil for a wet clutch and I was pretty reluctant to believe Synthetics were the 'way to go'. After experiencing using a 100-1 premix situation on Trials bikes (both modern and Classic) using Synthetic oils, I became pretty interested in why it works.
In simple layman's terms -- try frying an egg in petroleum based oil, then do the same with a good quality synthetic ---- I'd eat the synthetic one first!!
There have already been a few scientific facts bandied here, that only cloud the issue of what oil to use in certain conditions, so -- here's my humble recommendation.
Back in 'the day', a lot of engines used 'communal' oil for both lubrication for the crank/cams/top end, as well as the clutch/primary, and I always considered it was that way for 'job security' for the factories, as when the clutch plates shed both friction and steel bits, it all found it's way through the oil pump -- and ultimately the rest of the engine. Those guys were pretty sneaky!! Many wet clutch bikes still use the same system, although materials and OILS have come a long way, and the attrition is definitely not anywhere as bad as it used to be, it's still an area where regular oil changes -- no matter what oil you are using are necessary to keep your engine in top form as long as possible.
IF - a modern manufacturer stipulates a certain oil --- DON'T argue.
IF you have been running the bike on petroleum based oil for any length of time (thousands of miles) -- keep using the same oil until you need to rebuild the engine.
Reasoning here is from my own findings, that seals get 'conditioned' to the oil they were 'born in', and if you change from petroleum based to synthetic after major mileage - expect problems with leaks.
I've seen it happen a few more times than it takes for a 'fluke' to rear it's head!!
My race bikes are fired up with petroleum based oils -- just to get ring seat, and immediately live on Synthetics -- usually Catrol Syntech -- a great oil - as expensive as it is!!
All the modern wet clutch bikes I deal with, I stipulate Mobil 1 4T 10w40, which is fully synthetic and has no silly "friction modifiers" or whatever nonsense most Synthetic oils blart about.
I spent some time under the tutelage of a friend that worked in the oil business for a long number of years, raced (reasonably successfully) for a good few years, and heard all sorts of "Old Wives Tales".
Bottom line --- Don't short-change your motor with cheap oil.
If it is happy where it is -- why change?
Ride it hard - and put it away dry!!
Cheers,
Brid.
 
#38 ·
I have Mobil 1 20/50 in every cycle since they started selling it. Not MC specific. I have never had clutch slip, but then none of the 30 or more bikes had over 110 hp advertised.

I would not consider using the super low (<10/XX) in any motor I wanna keep. No science here, but I have always wondered if that was an mpg thing, not a best product for the motor.
 
#40 ·
I restored a rusty, corroded and dented '98 Adventurer from the Florida coast. After about five years, off and on... I got it back to very acceptable appearance. Fixed lots of things but basically left the engine alone other than adjusting valves. They bike shop that bought it from its derelict original owner had said it had good compression etc. before I bought it. Well, not knowing any better, I used synthetic oil in it. Low and behold, it fired right up. Has been running w/o complaint for about three years now. No clutch slippage. Just runs... very decently. In the basement now for some R&R... carbs leaking some so I have a little winter project.
 
#46 ·
When I first saw this thread I said to myself, "Oh-ohhhh... oil thread.":eek:

So with no action for a day or two I ventured in and sure enough, first post I see, which is the last post, is Dean's.:D

That said, I'll share my recently oil learnin' experience here and add to the confusion.

I recently aquired a 1939 Indian 439. As most will know, this is a very valuable bike. I know very little about these and am in the middle of the learning process. The guys who play with real vintage machines (not the slightly long in the tooth tarts that we discuss here) have more legends, rumors, theories, superstitions and other mumbo-jumbo about oil than all of us here, combined. So, rather than sort thru all the BS, I decided to take it to the mountain. Fortunately for me, the guy sitting on the mountain is Irv Truax, a recognized Indian 4 expert and rebuilder and the man who rebuilt my engine back in the 90's. Irv said that the general concensus is that the oil to use in that engine is Amsoil racing 20W-50. The Four is a wet sump, wet clutch with clutch plate technology (until recently) by the Flintstones, shares the oil with the tranny and no oil filter. So, probaby the worst scenario for oil. Oil change interval is 500 miles, and that is the original OEM recommendation. I did not discuss this point yet with Irv, but suspect that is due to no filter and the shearing action of the tranny on the oil.

So, that oil is good enough for the Indian Four, it should be more than adequate for our modern Triumph engines. Before somebody starts to argue the roller bearings skidding in the races point, keep in mind that jet engines use synthetic oil. It was originally created by the Germans during WWII for war machines which included aero engines. When jet engines came into being, syn oils were required due to the high engine temps which would cook fossil oils. And all jet engines run on roller bearings.

So, although I would not suggest running it in an engine that has not been rebuilt and thoroughly cleaned because of the risk of dislodging old crud and maybe plugging an oil passage, I would consider running it in a rebuilt engine once it has been broken in.

regards,
Rob
 
#47 · (Edited)
Hi there.

I don't know the theory, but I can speak from practical experience.

Last year on the Iron Butt Rally, I used Castrol GTX Semi Synthetic in my 1969 T150. I rode in temperatures from near freezing to 120 degrees farenheit, from below sea level to nearly 12,000 feet, covering more miles in 11 days days than some "classics" will in 11 years and the oil worked well.

When we did the first oil change during the ride at just under 6000 miles, we had some of the oil analysed and the general synopsis was that it would have covered a further similar mileage without any major problems

As I say, the theory I cannot speak about, but my experience leads me to suspect that using semi (or even fully) synthetic oil in your T160 will be no problem.

Regards

John Young
 
#48 ·
I spoke to a Spectro Oil rep at a dealership open house today, and also someone at a vintage bike shop, and they both said to use non-synthetic oil with a high zinc content. The Spectro guy recommended the Spetro 4 oil; the other guy said Castrol GTX 20W50, as specified in the shop manual, because he claimed it had the highest zinc content of all standard oils.
 
#49 ·
With all due respect, reps are salesmen! I used to be a salesman and would tell a customer anything to make it seem genuine. It's all lies!

As I said before, people who say anything bad about synthetics just don't understand oil.

Sent from my GT-I9100 using Motorcycle.com Free App
 
#52 ·
Actually the term synthetic itself is misleading. Several years back the oil companies were going after the true synthetic guys and the courts decided and I believe API, that you could use the term "synthetic" to describe your oil if it met certain specs. So, that means it can be labeled synthetic, yet be fossil based oil.

regards,
Rob
 
#54 ·
Hope its real synthetic in the Uk because i just bought 600 litres for my repair garage.A few comments about what it might or might not do to bearings etc.I am not against the stuff and use a lot of it.I just feel i made an error putting 0/40 in my old Triumph.
turning this into an oil thread yet again,The 20/50 Mobil vee twin oil is great for an old Triumph
 
#56 ·
It's been a long while since I've read thru the Amsoil website. I do remember that they listed the various syn oils on some scale that ranked them.

Everytime a discussion comes up about oil, I post this link which I find to be an excellent resource on oil written by somebody that did the research work to develop some conclusions. It answered some questions I had as well as changed a beliefs I had regarding oil.

http://www.calsci.com/motorcycleinfo/Oils1.html


I'm doubtful that there will ever be a consensus on oils. Think about it, most of us base our comments on either first hand experience with a few bikes, or on third party info, such as the thread below. If you talk statistics, one bike failing with a certain type of oil in it, does not necessarily mean the oil was the root cause. It might have contributed, but there could be other factors that went unnoticed.

And I think oil threads will continue to abound because new folks come along every day and have the same questions that many of us had when we first started. I tend to believe that the only folks who are informed enough to truly make intelligent decisions regarding oil types are folks in the oil industry, OEMs of vehicles and in the private sector folks like race teams, very seasoned dealer/repair shops and maybe restoration shops. I'm the first to admit that I know squat about oil other than what I've read. Yet I can probably make a good argument for using a type of oil given what I've learned. Does that make me right? Certainly not. When all is said and done, the same mantra ends being said during every oil thread and it probably the only thing all will agree on when it comes to oil selection for street motorcycles. Use a quality oil, of the proper rating and specification, and change it per the OEM guidelines or sooner and you are all set.

regards,
Rob
 
#57 ·
Jeez - I wasn't aware this would go on so long !! I guess it's 'another oil thread' :eek: :D
The only post I've made was based on honest findings, and a long few years seeing results of 'oil abuse' and - conversely, great results from the correct oil being used in the right application. An old friend of mine worked in the oil industry when synthetics were becoming more available, and once told me "It's hard to find a (named) 'bad' oil in this day and age. Just don't expect miracles from any oil".
He was referring to the fact that, in any application, any oil will NOT negate poor engineering - whether it be from manufacture or substandard mechanical prowess on the behalf of 'rebuilders'.
A few interesting points raised here - however, nothing to remotely make me veer from what I know and abide by.
Cheers,
Brid.
 
#58 ·
The last time I had it serviced the local shop put Amsoil in my Subaru WRX (I know, it's not a motorcycle, bear with me for a sec). I've always used dino in it and it just went over 100K miles. I am now getting a little oil seeping from the valve seals. The same thing happened to my Mazda MX6 when I tried synthetic after years of using dino.

Anyone know if a little extra seep from the seals a normal side effect when switching from dino to synthetic?
 
#59 ·
There are a lot of urban legends surrounding syn oils, but weeping seals on high mileage vehicles is a common known problem. If you call Amsoil and talk to them, they will (or at least they used to) not recommend you switching to syn if you have high miles on the vehicle.

Syn oils do an amazing job of cleaning out the crud in your engine. And one of those areas is worn seals. As I understand it, they can become packed with crud and when the syn cleans them out, they start to leak. I had a friend have this happen when he moved to Mobil 1 on his dump truck fleet. Each new truck used syn oil and when he only had a few old trucks left, he switched them to syn and they leaked.

regards,
Rob
 
#62 ·
The concern that has been voiced by others, although I don't recall any instances where this actually occured, is that the cleansing properties of syn have the potential to loosen up crud in your engine and circulate it thru the bearings, since there are no filters on these engines. In addition, their is thought to be a risk of some large piece of hardened crud coming loose and blocking a key oil port, such as a piece in the sludge trap coming loose.

My personal opinion, for whatever that is worth, is that if you run the bike regularly, you will probably slowly clean your engine a little at a time and with each oil change more old crud will be removed. But if you let the bike sit for long periods, it could have more potential to work at larger deposits without circulating them and when you start the engine after that period, could have a slug of crud run thru with the potential to plug ports and passages.

It's all conjecture as far as I can tell. I don't believe anyone has posted an example of syn oil destroying bearings with crud or old crud coming loose and plugging a port and killing an engine.

And maybe, and I do mean maybe, the apparent lack of cases where syn oil has caused engine destruction or severe damage might very well be telling us that all the concerns voiced, mine included, are just a bunch of hooey.

regards,
Rob
 
#66 ·
Same old debate

The great oil debate for motorcycles continues to pretty much mirror the now passe oil debate for automobiles. Yet even today you're not going to convince the guy that insists on running single weight non-detergent oil in his vintage vehicle because that is what the owner's manual said. Never mind that multi-grade oil was still in development and synthetic oil was a science fiction story at the time of printing.
Running synthetic in your bike is an improvement over running conventional oil. Your bike actually will run cooler as there is less friction. Synthetic oil is more stable and more readily maintains its proper viscosity with changes in temperature which with air cooled mots is more critical. Synthetic oil has uniform long chain molecules that provides a better friction barrier. Conventional petroleum based oils are chemically different in that they are "cracked" from crude oil. As such, they cannot meet the same standard of protection. I should add that you can use automotive synthetic oil in your bike although you may have trouble getting it in the recommended weight such as 20-50. But, if you do use automotive oil, it is very important use an additive such as ZDDP Plus to add the required metals such as zinc, phosphorus, sulphur etc. that especially your flat cam followers require. These metals were removed from modern automotive oils as they affect catalytic converters and emission standards. The only limitation to using synthetic is that you should be using an oil filter. True synthetic oil is less likely to hold most contaminants in solution as opposed to holding them in suspension, A quality oil filter readily removes these suspended contaminants. Also, the type of oil you use should not affect a multi-plate wet clutch. If it slips using synthetic then it slipped using conventional oil with perhaps the only difference being that the conventional oil more likely allowed a contaminant buildup such as sludge to help bind the worn plates (or worn springs). Similarly synthetic oil does not cause oil seals to fail. However, if your oil seals are dried and hardened up having been denied the beneficial lubrication and cooling of the oil because of a sludge buildup and suddenly fresh synthetic oil washes the contaminants away, yes you will get seepage. A seal in good condition with synthetic oil is less likely to leak given the uniform properties of synthetic oil.
 
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