HEADS UP!!!

Site upgrade in progress... Core site functions are working, but some non-critical features/functions will be temporarily unavailable while we work to restore them over the next couple of weeks.

Please post any bugs you encounter, but before you do, check to see if it's already listed.

Thanks for your patience while we work to improve the community.

Sign in to follow this  
Followers 0
Jack Roberge

Oil Type

10 posts in this topic

I just went to buy a few liters of Mobil 1 15W50 for my XR650L. Every store in town has replaced it with Mobil 1 5W50. Has anyone had good luck using this weight of oil in their bikes?

Share this post


Link to post
Share on other sites

Should theoretically be better- the difference is the first number which is an indicator of how thick the oil gets at lower temperatures (like in BC in the winter). The 5 weight won't thicken up as much as the 15 when cold, so you'll get better lubrication at startup. At operating temp you'll still have a 50 weight regardless of which one you use. Mobil know thier business; I'd use it without worry.

Best,

Robert

Share this post


Link to post
Share on other sites

Are you using the automotive mobil or the motorcycle oil? There is a diff. Not sure on the auto mobil but make sure it does'nt have the energy conserving label or your clutch wont like it.

Share this post


Link to post
Share on other sites
I just went to buy a few liters of Mobil 1 15W50 for my XR650L. Every store in town has replaced it with Mobil 1 5W50. Has anyone had good luck using this weight of oil in their bikes?

Keep in mind the greater the weight range (ie: 5w-50 vs 20w-50, etc.) the more Viscosity Index Improvers (VII's) that are present. VII's are polymers added to the base stock (the natural/original weight of the oil) to keep it thick/thin at certain temperatures.

When cold, VII's coil up, and can flow with the base stock viscosity easily. When they heat up, they stretch out, and create a thicker oil to compensate for heat-related thinning.

OK, so all well and good, until the oil is put in a bike. Apparently, the transmission gears tend to mutilate these VII's over time, and not a whole lot of runtime, either, which reduces the resistance to flow at higher temperatures. The net effect is that the original 5w-50 may be like a 5w-30 or 5w-20 after 1500 or less miles.

It is best to buy a oil with a weight range closest to your intended use/climate since there are less VII's present.

This is a *very* controversial subject, but when you get the time (there's a lot of info here) read this:

http://www.nightrider.com/biketech/oiltest1.htm

http://motorcycleinfo.calsci.com/Consumables.html#Oil

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

Share this post


Link to post
Share on other sites
Keep in mind the greater the weight range (ie: 5w-50 vs 20w-50, etc.) the more Viscosity Index Improvers (VII's) that are present. VII's are polymers added to the base stock (the natural/original weight of the oil) to keep it thick/thin at certain temperatures.

Not generally true for polyalphaolephin (PAO) -based synthetic oils which have naturally wide viscosity indices. Used to do a lot of work with Roush Performance; one of the engine calibrators there told me that "Mobil 1 is the best widely available oil you can buy." I wouldn't use something like Castrol Syntec which isn't actually synthetic, but the M1 is a no-brainer.

Share this post


Link to post
Share on other sites
Not generally true for polyalphaolephin (PAO) -based synthetic oils which have naturally wide viscosity indices. Used to do a lot of work with Roush Performance; one of the engine calibrators there told me that "Mobil 1 is the best widely available oil you can buy." I wouldn't use something like Castrol Syntec which isn't actually synthetic, but the M1 is a no-brainer.

Good point, but readers should keep in mind that it is very applicable to the majority of oil on the shelf, both dino and synth.

I run MX4T (M1 for bikes) in my YZF600 for the reason you pointed out, plus MX4T is good for an extended change interval (time purposes, not high-mileage purposes).

My XR's get Rotella 15w-40 or Castrol 20w-50.

Share this post


Link to post
Share on other sites

I ran Mobil 1 15-50 in my XR350R (7 years) and my Transalp (50,000 miles). Never touched the clutch on either and while the XR used some oil on start up, it never was a real problem.

I run Mobil 1 5-40 in the winter in three of my current vehicles: XR200 and 600, and my wife's WRX. The 600 doesn't clatter when cold (20 degrees) with the 5-40.

As an aside, my commutermobile 1993 Geo Metro (1L 3-popper) uses a quart of oil every 2 gallons, an 8:1 mix. It smokes like a chainsaw but doesn't foul plugs and still gets 55mpg.

"O"

Share this post


Link to post
Share on other sites

After reading the articles suggested by phuzz it seems to me that motorcycle oils are just a waste of money and a hole bunch of marketing hype. I think that the automotive Mobil 1 5W 50 will work just fine and most likely better than a lot of other oils.

Share this post


Link to post
Share on other sites

Phuzz once again makes some very good points!

Mobil1 is a very, very good oil the only word of caution is make sure whatever oil you use does not contain a "moly" additive (wreaks havoc on the wet clutch)

I have been very impressed with the shell rotella products.

I believe that as long as you use the correct weight for your climate and change oil regularly, all will live fine.

I must admit though I have been using the Belray Thumper oil in a 20/50 weight with good results. It is a very thick oil that holds its viscosity well over the miles, but would not reccomend this weight for BC probably a 5/20 for winter time.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0