Synthetic in wet clutches

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I keep getting told that synthetic will slip in a wet clutch system bike. That's most of your metric that shares all the same oil together. Is there any truth to this or anyone experience it? Thanks
 
not if the oil is motorcycle specific. there are many motorcycle synthetic oils. Even most walmarts carry M1 and valvoline synthetic motorcycle oils.

certain automotive specific oils contain friction modifiers that do not work well in conjunction with wet clutches. the synthetic isnt the issue, rather the type of friction modifiers in the oil.

the best bet is to run and oil that is motorcycle specific. many of those oils are synthetic.
 
From what I have seen and read, I think in real applications the problem of a wet clutch slipping is more of a question about how much of certain additives are in the oil, (such as the additives that are very slippery) and in general not as much about the base oil itself. Though if one were to use something like a very thick oil, a thick viscosity would prevent the surfaces from having enough friction contact.
 
I used Havoline 5W40 PCMO in my Suzuki GSX-R. (what we sold at Western Auto)

No clutch problems whatsoever. IIRC, it's a Group III though.
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I used BelRay Synthetique in my Kawasaki ZX600C for the first 40,000 miles. Motorcycle oil.
 
As long as it doesn't say energy or resource conserving on the API label on back you'll be good to go. Generally Xw-40 weights won't have the troublesome friction modifiers. If you use a bike that needs Xw-30 weight make sure to carefully check the API symbol for the energy or resource conserving label. I've always been safe buying automotive Xw-30 oils that are designated high mileage. These tend to not be energy or resource conserving, but be careful some do have the label.
 
I used Mobil 1 years ago before there was a specific "motorcycle" oil made and I never had a problem and I raced bikes back then.
 
Been running many brands of synthetic in our metric track bikes for many years and never had any clutch slipping issues.

Lot's of oil misinformation out there and it seems to be growing.
 
Originally Posted By: dslofti
I keep getting told that synthetic will slip in a wet clutch system bike.

You have a real knack for rehashing old wives tales. Whoever it is that keeps telling you these urban legends, you should probably consider staying away from them.
smile.gif


Weren't you sent on a vacation from BITOG recently for starting a similar discussion?
 
As long as it has passed the JASO MA or JASO MA2 criteria it is compatible with wet clutches; whether its full syn, semi-syn, or dino doesn't matter. Its the JASO rating that matters.
 
Back in the early 70's a cousin of mine who weighed more than he should for a highschool kid, bought a small motorcycle (less than 125 CC's but I don't remember the actual size, probably something like 80 CC's) and put a can of STP oil treatment in the oil that also was the oil for the wet clutch. That poor little clutch slipped so bad it would not even go up a small slope of a hill. The STP oil treatment was very thick oil. It flowed out of the can like very cool honey would flow. And considering that the small engine on this small bike did not hold all that much oil in the first place, meant that the can of STP oil treatment made up a considerable amount of the oil in that engine.

He had to take the entire engine apart and clean every part, and then put it all back together. It was a long project for someone who was fairly new to working on anything with an engine, and basically the entire bike spent the winter in pieces stored under his bed. But he got it back together in the spring and it ran fine.

So yes Virginia there is such a thing as oil that will prevent a wet clutch from working. But if you want to recreate this problem, probably half the problem is having an big person on a bike with a very small engine, and therefore a very small clutch.
 
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Originally Posted By: 2010_FX4
Rotella T6 in 5W-40 is a synthetic and has the JASO-MA rating.


I've been using this too, zero issues. Also use it in my mowers, generator, tiller and pressure washer.

Bob
 
I use Shell Rotella T6 5W-40 in my 06 Yamaha V Star 650, as well as in our two atvs.

In my Sportster, I use Mobil 1 V-Twin 20W-50 in the engine and primary/clutch/transmission.
 
I have used a few Synthetics in my Triumph S3, including RedLine 15/50, Triumph badged Mobil 1 15/50 4T, and the 10/40 4T. Currently using Mobil 1 Silver Cap 15/50, which I have used for thousands of miles without clutch slippage. Still on original at 43,000 miles.
 
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Originally Posted By: dslofti
I keep getting told that synthetic will slip in a wet clutch system bike. That's most of your metric that shares all the same oil together. Is there any truth to this or anyone experience it? Thanks

I sure wish I knew about that earlier, I have 77k miles on my 1100 V twin Honda all of it with synthetic oil. Oh well too late for me I guess. Just Kidding

Go use any of the Shell T oil in your weight. I buy the T6 or T5(if its on a very good sale)

ROD
 
I used to use Rotella 5w-40 in the wife's Shadow for a few years (gone now), but know plenty others using it and haven't heard any complaints yet. Seems more and more are going to it each year.
 
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