Mobil 1 5W-50 Fully synthetic

[EMS]

. I have run Mobil 1 5w-50 in my Harley for years. No problem with clutch slippage, .

The clutch in your Harley should run in the primary oil, not the motor oil. Unless you use the same 5W50 for your primary also. As I am totally not sure what actually the requirements are,that's the only oil I buy from a Harley dealer.

[Kool_Biker]

Thank you ALL for your help. Certainly, a lot of my questions have been answered.
As my problem is now low pressure in my newly rebuilt Z 1000 engine, I will start a new thread, under ENGINES, more focused on the subject matter.
Thanks again, Aris

[EMS]

Sorry about that Mike. Wal Mart carries a wide range of Mobil 1 out here.
Best,
Phil

Eureka! Found the 15W50. At Autozone, of all places, which wasn't even shown on the Mobil1 site as a dealer. Only in quart containers, however, and the price is $7.99 Ouch.

[Mike Cecchini]

Good thoughts and comments Randy. There's just one thing I'd like to comment on and that is the myth that synthetics are no good for breaking in a motor. Many people seem to think that synthetics are too "slippery" for the needed ring brake-in procedure, but Mobil 1 disproved this many ago when they showed their synthetics were fine for engine break-in procedure in all forms of cylinders and ring combinations. Also, a retired Mobil 1 lubrication engineer (George Mason) came on the Ducati Monster List back in 2009 and blew all the cob-webs out of the myths and old wives tales about synthetic oils that have been around for decades.......especially breaking in a new motor with synthetics.

Mr. Mason went on to say the real reason not to use synthetics for engine break-in was it was just a waste of money and product because break-in oil should be changed several times during the break-in and any SG/MA rated dino (cheaper) oil would do just as good........but synthetics are designed to run for 2x--3x times longer than dino oils......why throw expensive synthetic oils in the trash when cheaper dino oils would do the same job for the limited time they were in the engine. So he recommended using dino oil for the 2--3 oil changes, then once the engine had puked all it's break-in debris....... then go to a full syn and enjoy it's extended lubrication qualities.

Btw....... your HD motor runs cooler because you've reaped on of the benefits of a lighter weight oil......and you can run a lighter weight oil because of the superior film strength and lubricating properties of a synthetic oil. This was one of many things Mr. Mason told us on the Monster List...... "thinner oils conduct heat better than heavy oils, so use the lightest weight oil the engine manufacturer allows, avoid the common misconception that heavy oil is better..... it's not."

I specifically asked about the CBX engine and he said not to go past Honda's 10W--40 recommendation and Mobil 1 4T 10w-40 SG/MA rated oil was the perfect oil for the CBX.

Note: the Mobil 1 15--50 is a car oil. http://www.mobiloil.com/USA-English/Mot ... 5W-50.aspx You might want to consider a "SG/MA" rated motorcycle oil like Mobil 1 20W-50 "V-Twin" oil made specifically for your bike. http://www.mobiloil.com/USA-English/Mot ... 0W-50.aspx

$.02.

[viciouscycle]

The clutch in your Harley should run in the primary oil, not the motor oil.

Duh! What was I thinking You are absolutely correct. In fact that is precisely why for the Harley, I don't mind using car rated oil that I would not use on any of my other bikes. As far as I am concerned there is no difference between the engine in the Harley and the engine in my '68 VW single cab, both are air cooled, push rod 40's designed motors. In an American Iron article on oils some time ago, the Mobil 1 50 weight car oil was shown to be superior to Harley's own synthetic.

Mike, what you say about synthetics and break in makes a lot of sense to me. Again, from a Harley perspective, Harley for years down right condemned the use of synthetics in their engines until they started marketing synthetic oil themselves of no particular special breed and since then, of course that is what they recommend for all engines now. After reading your response I took a second look at the Motul oil I use for the Hondas and sure enough, 10w40.

[Mike Cecchini]

Good on ya Randy........ thanks.

[Kool_Biker]

BTW does anybody know the pressure below which the engine oil light comes on?
It never comes on with the engine running, even with an indicated ~10 PSI on idle (very hot). Is this right?

I removed the oil pressure switch from my bike.
On the side it was marked 'P0.3', which tested well with my Mightyvac and multimeter at about 0.3 Bar or 4.35 PSI.
So this is the approximate pressure, below which you would get the oil warning indicator to come on.

Aris

[EMS]

As far as I am concerned there is no difference between the engine in the Harley and the engine in my '68 VW single cab, both are air cooled, push rod 40's designed motors. .

Again, I am not 100% sure, but I think the Harley crank has roller bearings on the journals... This was one reason why Harley always pushed their own oils.

I agree with it being a myth about the synths not suitable for break-in. I have 4 vehicles (the oldest one was built in 1990) that came with synthetic motor oil from the factory. They run well.

[Mike Cecchini]

Roller crank or plain crank...... makes no diff. Dino and syns work the same. Mobil 1 and Bevelheads List (many roller cranks there)......now finally understand and agree.

Bevelheads were the hardest to convince that syn oil is head and shoulders above dino as Ducati recommended only straight 50 wt for the roller cranks. They went tooth and nail for over a year, each camp adamant. Then Cook Neilson finally chimed in and told all that he used full syn oil when he won Daytona and all went silent.

Syns do work on roller cranks and exactly why Mobil 1 came out with the SG/MA rated "V-Twin" 20w--50 oil for HD and Ducati engines of all years. It's so hard to dispel myths and old wives tales after so many years.