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Changing oil brand/type

  • Thread starter Thread starter gert du prez
  • Start date Start date
G

gert du prez

Guest
Hi,

I currently run Castrol GPS 10W-40 and would change to Mobil Delvac 10W-40 (which is a Heavy Duty Truck diesel engine oil).

What should I consider ? just a normal oil (+ filter change) ?
any chance that the residu of the Castrol after the oil change will 'fight' with the new Mobil oil ?
Do I need to change the new oil more frequently the first time to really get rid of the leftover Castrol-new Mobil combination ?

thanks

g
 
Just do a regular oil change and don't worry so much. The oils will mix just fine.
 
As much fuss as everybody make on forums and other places oil is oil.As long as it's not the energy conserving stuff you will be fine.
 
I used to believe that "oil is oil", then I started reading on the Bob is the Oil Guy forum and learned differently. I will say that most oil will work, and unless you plan to keep the bike for a LONG time the type/brand of oil is unimportant. For example, motorcycles without catalysts benefit from an oil with lots of zinc and phosphorus, something which has been reduced in auto oils. That's why diesel oil is so good for bikes; it has about 25% more of the good high pressure additives. Sure, lots of people say "I've never had any problems with brand XXX auto oil", but what these people don't know is whether or not there is incremental wear inside the engine they can't see. I don't understand why anyone would use auto oil when diesel oil is typically on the shelf right along side and is often cheaper.
 
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Whichever oil you use, look at the specs and make sure that it has a JASO-MA certification.

This indicates that the oil has the proper additive package to be used in a wet-clutch system.
 
Whichever oil you use, look at the specs and make sure that it has a JASO-MA certification.

This indicates that the oil has the proper additive package to be used in a wet-clutch system.

An MA cert is not strictly necessary. Most of the common diesel oils do not have this cert (other than the newest Rotella formula) because diesel engines don't use a wet clutch and it costs money to run tests and get the cert. Regardless of not having a cert I've never heard of any of the typical diesel oils causing problems with wet clutches.
 
I've used all kinds of oils in my bike.
off-brand cheapy diesel oils, Rotella, expensive specialty oils.

No clutch problems to report, it all ran the same!

-------

Just change the oil to whatever you want.
(people tend to make a big deal out of the whole "oil change" thing.....it's just oil, and it's just a GS bike, so change it to whatever you want!) Lol

I know people that have 200-300k+ on cars/trucks and ALL they used were the Cheapest Oils on the market, and the Cheapest Filters....
 
An MA cert is not strictly necessary. Most of the common diesel oils do not have this cert (other than the newest Rotella formula) because diesel engines don't use a wet clutch and it costs money to run tests and get the cert. Regardless of not having a cert I've never heard of any of the typical diesel oils causing problems with wet clutches.


Nessim, I'm not trying to be a dick, so please don't take what I'm going to say in the wrong way.

I can GUARANTEE that any oil with an JASO-MA cert will work in a wet-clutch system. Although some oils without this cery MAY work in a wet-clutch system, there is no guarantee that they WILL work. So, if you're dispensing advice to Joe Average who has the choice between two simarly priced oil brands and one brand has a JASO-MA cert, I have to reccomend going with the oils that are indeed certified (regular Rotella and T6 Syn Rotella).

I can also GUARANTEE that modern automotive oils with an energy-conserving additive package WILL cause a wet clutch to slip. Simply because a user has not noticed a slipping clutch does not indicate that the clutch isn't slipping.

I cannot emphasize enough how regular car/truck motor oils should not be used in a wet clutch system.

When the GS bikes rolled out in the 80's, standard car/truck motor oils did not have the additive pacages that they do today - oil has made leaps and bounds in additive technology. Whereas a bike may have been able to use car/truck oil brands of the 80's, they certainly cannot use the stuff that is on the shelf today.

Here are the most easily found JASO-MA compatible oils in the US today:
1. Mobil 1 4T 10W-40 motorcycle oil (full-syn) - any auto parts store
2. Castrol 10W-40 motrocycle oil (non-syn) - any auto parts store
3. Shell Rotella 15W-40 diesel truck oil (non-syn) - any auto parts store or wally world
4. Shell Rotell 5W-40 diesel truck oil (full syn) - any auto parts store or wally world
 
If I change my oil to one of these diesel oils mentioned and IF I experience a slipping clutch problem as I've seen mentioned by some who do, is there something I can fix beforehand? What causes it to happen and why isn't it noticed until after the swap?

I'd much rather stop paying $25 for the 4 quarts and go with less but I don't want to cause more issues for myself either.
 
I agree about not using auto oil, but mostly because of the low zinc/phosphorus levels. It's true that Energy Conserving oils can mess with a wet clutch, but EC oils are typically low viscosity type oils, not often 10W-40 like GS bikes call for.

I don't care about the MA cert with regard to choosing diesel oil for use in my bike. I've used all kinds of different diesel oil (Mobil, Motocraft, Vavoline, Shell/Rotella (both old and new formulas)) and never had any issues with clutch slipage. That said, for those that want a certification behind their oil, the newest flavors of Rotella are readily available.
 
Note that the OP is in Belgium, not the US of A... hopefully there's no room for a Walmart in Belgium.

The Mobil Delvac will work fine. Switching brands of oil won't hurt anything.
 
I don't see the JASO-cert for the Delvac MX Extra 10W-40 in the specs below...dangerous for my beloved GS ?

Mobil Delvac MX Extra 10W-40

ACEA E7/E5/E3/B4/B3/A2,
API CI-4/CH-4/CG-4/CF-4/CF/SL/SJ,
MAN M3275, MB 228.3/229.1, Renault RLD, Volvo VDS-3/VDS-2, Mack EO-M Plus, Cummins CES 20078/7/6/2/1, Detroit Diesel 7SE 270, MTU Type 1, RLD-2
 
I don't see the JASO-cert for the Delvac MX Extra 10W-40 in the specs below...dangerous for my beloved GS ?

Mobil Delvac MX Extra 10W-40

ACEA E7/E5/E3/B4/B3/A2,
API CI-4/CH-4/CG-4/CF-4/CF/SL/SJ,
MAN M3275, MB 228.3/229.1, Renault RLD, Volvo VDS-3/VDS-2, Mack EO-M Plus, Cummins CES 20078/7/6/2/1, Detroit Diesel 7SE 270, MTU Type 1, RLD-2


No, there's no JASO MA spec on that oil, because the manufacturer simply hasn't bothered to do the testing.

But thousands upon thousands of motorcyclists all over the world have used this oil and all the many other brands of diesel engine oils for many years with no problems.

If that's not good enough for you, then you can either continue to waste money on motorcycle-specific oil or seek out Shell Rotella oil. As I understand it, there were no formula changes, but Shell recently completed the JASO testing for an MA rating and this is printed on their packaging (although you might still find an occasional older bottle of the oil that does not mention the rating.)
 
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