What oil should I use in my 2004 YZ250F

[Traxstar1825]

Hello everyone, I'm gonna make this short and sweet. It's that time again for an oil change and I can't remember for the life of me what I am supposed to use for the oil in my 2004 YZ250F. Any suggestions for the best oil to use?

[Hans Schmid]

[Bricktop72]

[Traxstar1825]

So I'm guessing rotella t 15w 40? Would that be good in my 04?

[Bricktop72]

Just now, Traxstar1825 said:

So I'm guessing rotella t 15w 40? Would that be good in my 04?

Not only is it good in your 04 or any other dirt bike, it’s also great for cooking and bedroom personal use. 

[Traxstar1825]

Not only is it good in your 04 or any other dirt bike, it’s also great for cooking and bedroom personal use. 

Awesomeness

[turbo dan]

No bullshit, Rotella T4 really is good stuff.  Better than a lot of oils that cost much more.

[DGXR]

I wonder if Rotella T6 (synthetic) 5w40 might be another good choice.

[turbo dan]

T6 shears more severely than the T4.  Both oils are mineral based, the T6 is just a hydrocracked mineral base stock.  Like many "synthetic" oils, it does not contain PAO or ester base stock.

Lots of guys run the T6 but viscosity loss will require more frequent changes.  The T4 holds up much better and is cheaper.

[mikeberish]

 It has been a while since I've been in the motorcycle business and I'm just getting back into it.  Back in the day we ran motorcycle specific oil because it had friction modifiers which worked better with a wet clutch.   As well, the loads in a gear box present shear on the oil which is different than in plain bearing or roller bearing type applications.  In fact, for applications in which the gear box was separate from the engine there were oils specifically made with increased resistance to shear.  Does Rotella do the best job for a wet clutch application and a gear box?  If so, why don't they advertise their oils for motorcycle use?

Just askin'

[turbo dan]

Rotella is JASO MA/MA2 certified.  Works great with a wet clutch.  Clutches want low viscosity oil, everything else wants high viscosity oil.  Many manufacturers base their recommended oil grade on a happy medium.  10w30 or 10w40.  15w40 is even better since it relies less on viscosity index improvers to maintain viscosity. 

Shear occurs in the gear stack.  Everything else in the gearbox runs on a hydrodynamic film.  The loads applied to the gear teeth exceed the film strength of the oil which grind down and chop up the long, complex molecules that most oils rely on to maintain multi grade viscosity at high temperatures.

Rotella is a mineral base oil and does depend on viscosity index improvers but the diesel engines it is designed for are not much easier on oil.  Over a 3000 mile interval in my Yamaha 600 it sheared down to a 15w30.  That's about as good as can be expected and the wear metals were all substantially below average so the viscosity loss certainly didn't have any detrimental effect on lubrication.

[DGXR]

Shell Rotella "meets performance requirements of" JASO MA/MA2 although it has not received any manufacturer approvals that I am aware of.  I guess they don't need to advertise for wet clutch moto since it practically sells itself.

[Yamadude333]

I’ve used rotella in most of my bikes but find most of them shift better with mc oil. You can get synthetic Mobil 1 4t at most big name auto stores. Manual calls for 10-40 I believe. I have an 05. 8-10$ a qt. They have mineral 4t also. Usually on an end cap. Not near car oils.

[mlatour]

I don't think it would be in Shell's marketing interest to include 'puny' motorcycles on a product which it's main target is the trucking industry & heavy duty engines.

It's already well known in the motorcycle community (on and off-road) that Rotella T is an attractively priced & good performing oil, so no promo required.

 

Many / most diesel rated oils despite not having JASO-MA certification will do equally well in dirt bike engines/gearboxes.

Myself use a store brand synthetic blend 10W-30 diesel oil in both my bikes.  (re-branded Citgo oil I think)

Edited June 28, 2019 by mlatour

[mx_599]

On 6/27/2019 at 3:43 PM, turbo dan said:

Rotella is JASO MA/MA2 certified.  Works great with a wet clutch.  Clutches want low viscosity oil, everything else wants high viscosity oil.  Many manufacturers base their recommended oil grade on a happy medium.  10w30 or 10w40.  15w40 is even better since it relies less on viscosity index improvers to maintain viscosity.

Thanks for your info, you seem to be well versed in this area. I thought in the last year or two there had been concern over change of formulations? Are we for sure it is still good? I don't think I am going crazy, but thought I had seen buzz on various forums that Rotella changed?

[turbo dan]

There has been talk about reduced zinc.  The used oil samples I had analyzed showed appropriate levels of zinc.  These were within the last year.  Wear metals well below average, some less than half of average.  Very good stuff for shared sump applications.

If the diesel guys start blowing up engines I will reevaluate my recommendation.  Until then, if it is good in compression ignition engines with 20:1 compression ratios producing thousands of ft-lbs of torque, it's good for bikes too.

[mx_599]

18 minutes ago, turbo dan said:

There has been talk about reduced zinc.  The used oil samples I had analyzed showed appropriate levels of zinc.  These were within the last year.  Wear metals well below average, some less than half of average.  Very good stuff for shared sump applications.

If the diesel guys start blowing up engines I will reevaluate my recommendation.  Until then, if it is good in compression ignition engines with 20:1 compression ratios producing thousands of ft-lbs of torque, it's good for bikes too.

Does zinc have to do with friction modifiers? I thought people were concerned about JASO " "  ratings being in question because of modifiers? I hear you on the "if diesels start blowing up" but isn't the concern for all us on the modifiers or not...and if that was so, the trucks wouldn't be hurt but our clutches would, correct? I believe you if you say still good, I just thought I read something that made me pull back. Is zinc a friction modifier?

[Babywolf]

Moble one 0w40 in my wr250f works great, fixes clutch

[oldnbold]

Does zinc have to do with friction modifiers? I thought people were concerned about JASO " "  ratings being in question because of modifiers? I hear you on the "if diesels start blowing up" but isn't the concern for all us on the modifiers or not...and if that was so, the trucks wouldn't be hurt but our clutches would, correct? I believe you if you say still good, I just thought I read something that made me pull back. Is zinc a friction modifier?

I don’t think zinc is a friction modifier but it is an anti wear agent.
Zinc doesn’t do well in contact with catalytic converters so it was removed from auto oil.

[turbo dan]

17 hours ago, mx_599 said:

Does zinc have to do with friction modifiers? I thought people were concerned about JASO " "  ratings being in question because of modifiers? I hear you on the "if diesels start blowing up" but isn't the concern for all us on the modifiers or not...and if that was so, the trucks wouldn't be hurt but our clutches would, correct? I believe you if you say still good, I just thought I read something that made me pull back. Is zinc a friction modifier?

Friction modifiers are commonly found in low viscosity automotive engine oils to improve fuel economy.  They add things like molybdenum to make the oil as slippery as possible.  These additives can cause clutch slippage.

I'm not at all concerned about the clutch.  I was primarily concerned with Rotella's ability to protect tranny parts and maintain viscosity in a high shear environment.  After having two samples analyzed with great results I recommend it every chance I get. 

If Shell were to compromise the formulation in any significant way you would see diesels blowing rods through the block.  Areas like the wristpin simply require a minimum amount of extreme pressure lube.  I don't think we have anything that compares in the dirt bike world.  As long as the oil doesn't shear down excessively or interfere with clutch operation, it is perfectly suitable.