Put your opinion on the oil I'm using

Hi people

I have decided to start using Shell 20w50 API SH rated oil in my '82 Seca DOHC motor. Yep, its a car engine oil and it meets the owner's manual's recommended rating (20w50).

I know that some say "JASO MA only" and some say "Anything is fine as long as you change regularly". I have read a number of articles about it.

What do you think about that?

its fine.

Thanks man.

It is not fine, never use car engine oil in a motorcycle with a wet clutch it will start to slip. And when it does you will not only have to replace your oil but also your clutch plates wich will be saturated with the wrong oil. Because car oils have additives you dont want in a wet clutch

Let's break this down- 20w50- fine choice. No problem there.

Shell- quality oil maker. My brand of choice too.

SH rated- usually SH rated oil is fine for motorcycles. The major concern with car oils are with this rated SJ or higher which are "energy conserving." These are more likely to have friction modifiers (including molybdenum) which can cause slipping in a wet clutch.

Now, this is not to say all SH rated car oils are OK for motorcycles. That would take a higher level about specific oils than I have. Here's the issue: Even at SH stages, phosphorus and zinc were being reduced for emissions standards. Both of these are positive additives for older engines like ours, but it is more confusing that that. My understanding that the zinc and phosphorus standards (possibly others) do not apply to 20w50 oils the same as "thinner" oils, so they may not have reduced levels.

Again, I just don't know about individual oils. Also, while many or most SH oils, especially 20w50, may not have the "friction modifiers" that can cause clutch slippage, they also may have such modifiers....and add this complication- even with those modifiers, it may not cause a problem. The last issue is that car oil is not usually designed to handle the shear forces present with the meshing of gears in a transmission. This causes the oil to break down faster. probably not an issue if you change oil every 2000 miles, but just know oil sufficient for 3000 or 5000 mile oil changes in cars should not be used that way in motorcycles.

With all this uncertainty, for me, I use motorcycle or oil intended for diesel engines. I use Shell Rotella T. I know it has adequate zinc and phosphorus, shear stability and does not have the friction modifiers that can cause problems.

In the end, the oil you have chosen is probably fine....but as you can probably tell, oil is such a complex subject that opinions often rule over facts because the facts are so difficult to discern.

I don't recall what oil I used when I rode back in the late 70's and early 80's but I'm pretty sure it was just automotive oil. Never had a problem in 30K miles. That being said, I never offer an opinion on Religion, politics or motor oil. You can lose friends quickly.

I run 10w30 in the both my '82 Seca's. They seem to run just fine with it.

Some of the "friction modifiers" are sensitive to heat and deposit based on heat and friction. If your clutch doesn't get put under extreme pressure,it should be OK for a long time.I too have used "car" oil in the past with good results.Oils have changed and do so every year as manufacturers try to keep up with government agencies specs for fuel efficiency with 0-30 oils,etc.Put this oil in a wet clutch,and you won't have a clutch for long.I've found 15w40 diesel rated oils to be the best for my needs in my bikes and trucks. lha

Listen to Houghmade. He has some good advice.
What has happend in the automotive industry is that thier cars have to meet tighter and tighter emissions laws. All cars have to have catalytic convertors now. On top of that they are forced by law to warranty the emission system for a much longer time. In fact the warranty on the converter is probably longer than the warranty on the rest of the car. The manufactures are not keen to buy you a new convertor every 4 or 5 years so they have worked hard to find out what makes one fail.
What they found was that an additive known as ZDDP (zinc dialkyl di thio phosphate) was fouling the convertors. So they had the oil manufacturers reduce the amount in the automotive oils. This was ok because the newer engines were built with this in mind. An example is the use of roller lifters in new engines. This is not so good for older engines with flat lifters though. ZDDP is an anti scuffing agent that helps to reduce wear. Without the ZDDP some older engines are having premature wear of thier cam lobes.
The problem was that the oil manufacures didn't tell anyone they had made a change. We were always told that the new oils were better and had the best latest additives so everyone with a old car thought they were doing the right thing.
So in short "I" would stick to motorcycle oils.

Stick with the Shell oil, but use Rotella-T 10-40 (or 15-40), instead. It's a diesel oil, and has the zinc and other additives removed from auto oils. And, it won't interfere with clutches.

Runningdog said:

Stick with the Shell oil, but use Rotella-T 10-40 (or 15-40), instead. It's a diesel oil, and has the zinc and other additives removed from auto oils. And, it won't interfere with clutches.

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That's what I said 2 posts back,and what I use on almost all vehicles. lha

I've been running Rotella T6 Syn 5W-40 diesel engine oil in all my vehicles for over 5 years. It's made by Shell and is pretty cheap ($20 per gallon when on sale).

The oil is not a true synthetic but it works perfect for me and as long as I change it every 3K in the bikes and 5K in the truck(Toyota suggested for conventional oils) I am good.

The ONLY issue with this oil is it has a higher ash content than normal oils and therefore is darker and might need to be changed sooner than other oils.

On the plus side is has a ton of additivies to reduce wear but does not contain any of the extended mileage additives which will cause clutch slippage in higher power machines.

I just bought 5 gallons of Rottella at wally world for $12.00 per and I figure that's a good deal I use it in 2 bikes,3 4x4 trucks and an antique tractor. With 15-w-40, in winter,just allow a minute or so warm up time,and go.Here where I live in Tn,we have short spells of really cold weather,bit usually 25-35 during the day is about all,so 15-w-40 is low enough in viscosity for my climate.In the "frozen wastelands" 0-20 would be better,I guess.When the temps get low enough,all oil gels and won't flow,In Alaska,The gas for the snowmobiles where I was had to be kept warm,or the oil would separate.and form a ball at the bottom of the tank,or so I was told. lha

i use the 4-stroke 10w40 motorcycle oil.

So what kind of lifters are in a 77 xs 400? I'm looking into this ZDDP stuff.

Your bike ,and all older bikes has a pushrod lifter system that is non-roller,and produces metal-on-metal contact. This type of engines and all older ones need zddp or some additive to protect the cam from wear. Diesel oils have good amounts of zddp,but new classifications of oils have little of this additive due to government regulations"looking out for the environment". lha

Why not regular 4 stroke motorcycle oil like Valvoline 10W-40?

Glad I found this thread as I was thinking of starting one on the subject.
I've read of the dangers of modern car oils for our wet clutches and am glad to avoid anything that might be bad.
The other day I met an old gentleman with an '85 Shadow 750. He got it with 20k on it years ago and now has nearly 150k. When he got it, he had a shudder in the clutch. M-C mechanic told him to use synthetic (M-C type) and it cleared up the problem and quietened down the engine considerably.
He attributes its use to his having had no problems since he got the bike.
He could be right - http://wiki.answers.com/Q/Can_you_synthetic_oil_in_a_Honda_shadow_750

Any advice on/experience with using motorcycle or diesel synthetics?

As far as I can tell folks the majority of the folks are saying Shell oil, but use Rotella-T 10-40 (or 15-40) diesel engine oil. I've got a gallon of it in my garage that I'm thinking of doing an oil change with after another 1800 miles. I think the last oil change from the previous owner of my bike used regular 4 stroke motorcycle oil. I'm going to top it off with the extra bottle of 10w-40 4-stroke motorcycle oil I've got. Should I worry about doing this?

happy61 said:

That being said, I never offer an opinion on Religion, politics or motor oil. You can lose friends quickly.

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Spoken like a true Boss! haha