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Synthetic oil for older inlines ?

20945 Views 44 Replies 29 Participants Last post by  Easy Rider 2

I tried synth in my 83 Kz750L. keep in mind that the motor has around 100,000 on it. It worked okay, but I started to get some leakage from the cylinder head and the clutch slipped a bit more than normal.

Other than that it ran fine. I wouldn't see any issues, but if I remember roght the YZF was liquid cooled correct? I'd think cheap old dino oil would work fine
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Because of the added friction modifers synthetic oil can cause clutch sllping. Mobil says that on their web site. That's why they have the inline four oil (unit gearbox) and their V-Twin oil (separate gearbox).
They're still selling full syn. 15w50, they just changed the packaging. Now it's gold cap
The ST got a great write-up in Rider this month, as did the Tiger a few months ago.

I'm still hot for a T100 in tangerine and white.
I used to use Mobile Delvac 1 when I bought my SV-650, it is as good as Mobile 1 but usually MUCH cheaper. I was always able to find it much cheaper at truck stops.

Not sure if this still holds the same as on this site I found it looks a lot more expensive then when I used to buy it. (scroll towards the bottom)
Yes, and McDonalds has a "Healthy Menu."

They say they do, but I somehow don't believe it.

I think Mobil will say anything that sells more oil.
Never talk about religion, politics, or oil.

I am a rotating equipment specialist with decades of experience with motorcycles and cars. Hot rod gearhead from the '60s. For motorcycles the two best choices are Rotella and Delvac. Both are diesel specific so they have extreme pressure additives that work very well in integral engine/transmission sets. Both are cheap and both will go 5,000 miles between changes (based on actual testing), even on well used engines.
Well, that's why I said "to my knowledge." Thanks for the info. Years ago I used to work for a manufacturer. I don't remember that ever being a problem, but perhaps Mobil 1 has experienced it. We did have a motorcycle specific synthetic, but I don't remember if it had an additive/formulation to prevent that problem.
wow i used to know twins named Rotella and Delvac. great personalities. the Tundra twins.
This is a good point about the diesel oils but I'm not sure it's as significant as it may seem. Lubricants are actually overengineered, so I don't know how much differerence it makes to the average rider that changes his/her oil every four or five thousand miles. I think a little research is in order.

We used to sell a hi-performance motorcycle-specific oil, (and if I remember correctly, there was an additive package in it to address this problem) but the inside scoop was that our semi-synthetic and synthetic auto oils did just as good of a job.

In theory, it's probably true, but this kind of stuff can be a little overplayed to create more differentiation for the different product segments.
I saw one at my dealer this weekend. Caspian Blue. Very nice. The only thing I was puzzled by was the weird nylon-like seat cover. I didn't think it was bad, just weird. The exhaust nozzles don't look quite as cool in person when you realize they're just three short pipes that stick out of a box, but they're still neat.

I'm trying to get my friend to ditch his V-Rod and buy one.
The lubrication superiority of synthetic oil is getting overblown. Apparently the oil refineries are making nearly the same stuff. Imagine what it costs to make different kinds of oil. They won't tell you that synthetic isn't any better than the regular petroleum oil, because they make more money selling synthetic. Toyota recommends the cheap $1.30 a quart oil in their cars.

What is more important is the viscosity and to some extent the additive packages. It turns out synthetic oil is slightly less viscous for the same viscosity rating, because it is a better lubricant and slips better. I tried running 20w50 synthetic in my Harley and started getting a little lifter noise. When I switched back to regular 20W50 the noise went away.

I also read an article from Kevin Cameron who said that the additive packages are overated for motorcycles, at least until the rpm reaches about 19,000 rpm. That explains why oil labeled for cars works OK for motorcycles. But, if you run at redline a lot maybe you should use motorcycle oil. However, Motorcycle Consumer News tested a lot of car and motorcycle oils and found no difference between them.

I've run Mobil1 15W50 car oil in my Triumph Speed 4 with no problems for the last 10,000 miles. It's cheaper than Triumphs' Mobil1 15W50, which I believe is exactly the same as the car oil.

Use the correct viscosity and change the oil frquently (2000 to 3000 miles). Gear boxes chew up engine oil fast. I noticed a change in engine vibration about 300 miles after an oil change in my old Yamaha Virago 750.

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Gearboxes can be hard on oil. With unit engines you may want to change oil more often.
102K on an NT650. Started out using Mobil1 15w50 later switched to Amsoil 10W40, which seems to hold up better (based on shifting feel) than the Mobil1. Oil changed once a year 5-8K miles. Bike still runs great, never been apart, no clutch slip. I would not hesitate putting it in an older motor as long as its had regular oil changes.
or hitting up the Deli owner for "protection" money
As an experiment I used Mobil 1 in my 1989 Pontiac Grand Am. I kept in in for exactly 100,000 Km (Approx 60,000 Miles I think). I changed the filter every 5000 Km and only had to top up with Mobil 1 at that time. That Quad 4 went for approx 350,000 km and was still running fine and not using oil, when a drunk turned left in front of me at an intersection. Try that with regular oil. I just did the the first oil change on my VFR and used Honda Oil and a Honda Filter. Why are Oil and filters from bike shops so expensive?
Yes they can be harder on it. But from what I remember about the lubricant business, the frequent oil change thing is a good part hype. They're in business to sell you more oil and filters. Notice that the vehicle manufacturers recommend oil changes far less frequently than the oil manufacturers push. The oils are actually far better than the oil people want you to know. When was the last time you had an oil related problem or a significant loss of performance that can be traced back to insufficient lubrication? Well, being that you change your oil so frequently, you probably haven't had any. How about someone you know?

I've never had a problem with a car or motorcycle because I didn't change the oil every 2000-3000 miles. I stopped doing it when I started working for the oil manufacturer and was told to stop wasting my money. Now I usually change the oil about every 4,000-5000 miles. Andm especially with synthetics, that's not even necessary. It's just an ingrained behavior.

The API (American Petroleum Institute) mandates a certain additive package to get the current year's approval (and the standards keep getting higher every year). That means all conventional oils with current API approval are virtually identical. In fact, as you mentioned above, many of them are the same oil rebranded. The synthetics and semis may differ a bit more, but they're all basically very effective. They just get there a little differently.

Of course, it can't hurt to change the oil more frequently. And if you want an extra safety margin and don't mind spending a few bucks, that's fine, too.
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Because they say Honda on them.

(or insert any bike makers name in place of Honda)
The synthetics do differ more in formulation, but they all basically work about the same. Conventional oils are all virtually identical. The API mandates the additive package for the current year's approval, so, naturally, the resulting oils are the same.
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