Why/how is motorcycle oil unique? Mobil 1 0w40 in my ATV?

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Jun 13, 2006
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NJ
Hi everyone,
I was recently in BJ's and the had a great sale on Mobil 1 oil. I picked up a six pack of Mobil 1 0w40 Euro oil for $26.00. The 0w40 oil seemingly has a great reputation in the passenger car oil section. Some people even claim it to be almost a "universal" oil.
I need to do a oil changes on two of my ATV's, identical 1988 Honda TRX300 4x4's. I believe the owners manual calls for 10w40 oil. Would the 0w40 Euro oil be a good option for both machines?
What exactly does "motorcycle" oil mean? How is it different from passenger car oil?


Thank you!
 
I vote yes you should use a motorcycle or atv type oil. I had a 2002 Honda Rancher 4x4 that used a shared sump with the engine/transmission. Even though mine didn't have a manual clutch lever perse but there's still a clutch in there. If you want to save some cash Walmart has the Valvoline oil for a good price.

 
If an oil is too slippery for a wet clutch the vehicle will not move when it has to carry a heavy load such as going up a hill. Years ago a cousin of mine put STP oil treatment in a small motorcycle with a wet clutch. He had to completely disassemble that engine and clutch and transmission and clean every part and put it all back together again before you could get it to work again. It would not go up even a slight Hill with him on it with the STP in the oil. I remember it very well.
 
If an oil is too slippery for a wet clutch the vehicle will not move when it has to carry a heavy load such as going up a hill. Years ago a cousin of mine put STP oil treatment in a small motorcycle with a wet clutch. He had to completely disassemble that engine and clutch and transmission and clean every part and put it all back together again before you could get it to work again. It would not go up even a slight Hill with him on it with the STP in the oil. I remember it very well.
Why did he do that!
 
Older manuals, like 1980s and earlier, may not specifiy a JASO MA clutch friendly rating because it wasn't an issue with most oils back in the day. It's the starburst oils that slip.
My 1954 Enfield manual doesn't specify anything other than 40 or 50 (separate primary for the wet clutch, but it shares a breather/weep hole with the crankcase so use the same fluid) That was in 1954 folks. It didnt even spec a detergent rating. Get with it and use oils as they are designed today.
 
Wet clutches have been discussed, another aspect is temperatures, motorcycle oils are generally not "energy conserving" and are thicker at high temps, which makes them more suitable for air cooled engines.

Air cooling may be on its way out, but there are plenty of them out there.
 
Older manuals, like 1980s and earlier, may not specifiy a JASO MA clutch friendly rating because it wasn't an issue with most oils back in the day. It's the starburst oils that slip.
My 1954 Enfield manual doesn't specify anything other than 40 or 50 (separate primary for the wet clutch, but it shares a breather/weep hole with the crankcase so use the same fluid) That was in 1954 folks. It didnt even spec a detergent rating. Get with it and use oils as they are designed today.
JASO T903 was born in 1998, so you'd never see it reference in any motorcycle OM until probably 1999 or 2000 and beyond.

https://bobistheoilguy.com/forums/t...so-ma-spec-full-synthetic.361375/post-6280109
 
As a general rule, hard working, air cooled engines like an HTHS above 3.8. This ensures adequate viscosity at the higher temperatures air cooled engines are likely to reach.

If you look at M1, 15W-50 it's HTHS is 4.5 (with the recent reformulation, I suspect it's unchanged) and that oil will work just fine in your ATV.

But M1 also makes a downright epic 10W-40 motorcycle oil, HTHS of 4.15 (by memory). Which is ideal for your use.

The 0W-40 has an HTHS of 3.6. That's a fine number for a water cooled engine, but just a touch low for hard working air cooled engines.
 
I need to do a oil changes on two of my ATV's, identical 1988 Honda TRX300 4x4's. I believe the owners manual calls for 10w40 oil. Would the 0w40 Euro oil be a good option for both machines?
What exactly does "motorcycle" oil mean? How is it different from passenger car oil? Thank you!

Motorcycle oil means higher cost and specific marketing... but both oils are remarkable the same... either the 0w40 or 10w40 will meet and exceed your mileage expectations...

Here are virgin oil samples of $4.89 a quart Mobil 1 Auto Oil 10W40
and $9.98 a quart Mobil 4T Motorcycle specific oil... the additive packages
are so similar that our wet clutch wouldn't know the difference...

full-45634-40107-mobil10w40v4t10w40.jpg



(warning additive package may not be current, check with the manufacture)
 
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Wet clutches have been discussed, another aspect is temperatures, motorcycle oils are generally not "energy conserving" and are thicker at high temps, which makes them more suitable for air cooled engines.
Zack
We say oil are graded on thickness but oils are actually graded on
flow... a 40 flows faster with less energy than a 50 which means a 40
will increase horsepower and decrease operating temps with no loss in
longevity...
full-45634-35394-viscositytest1.jpg
 
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If an oil is too slippery for a wet clutch the vehicle will not move when it has to carry a heavy load such as going up a hill.

Mercy Jim... there is nothing in modern engine oils to defeat a wet clutch in good working order... because
High mileage is the constant where all clutches begin to loose grip due to normal glazing and contaminates
that build up over use and not the oil...
 
Last I heard, oils tagged as "motorcycle oil" have very substantially higher ZDDP content than the same or similar weight in auto oil. xW40 auto oils have had greatly reduced zinc from 10 years ago. Personally, I'd stick to the recommended 10w30 or 10w40 in an ATV/motorcycle graded oil. I suspect it matters most in air-cooled engines. Many of those spec 20w50 oil.
 
Last I heard, oils tagged as "motorcycle oil" have very substantially higher ZDDP content than the same or similar weight in auto oil.

Hank
True but deceptive... Thanks to BITOG data we find the single most common
misunderstanding about motor oil is that higher zinc levels provide
greater wear protection. fact is more zinc provides longer wear protection...
but thats a moot point given the short oil change intervals owners favor...
 
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