I have a 2004 roadking and just changed oil with Mobile 1 V-Twin 20w50, pretty costly...For my Porsche I use Mobile 1 15w50 synthetic. for nearly half the cost of the V-twin version. I understand that the composition of the V-twin takes into account less or different lubrication specs for the wet clutch type of lubrication. My bikes primary is completely separate from the crankcase so that issue should not apply to my bike.

That being said is there any other reason why I can't use the standard Mobile 1 15w50?, which by the way also has very high tempurature breakdown resistance, if anyone was going to mention high rear cylinder temps as a reason. I tried to research with little success in evaluating the benefits of v-twin version vs standard Mobile 1 15w50. Thanks, John

 

Because car motors cruise at 1500 rpm and bikes cruise at much higher Rpms. Especially jap bikes. high heat high Rpms and we take 20 -50 not 5-30.

The additives in the motorcycle oil are supposed to protect our motors as they should be protected. Youse have to be a chemist to know for sure. I'd say it's true. Use the right stuff for the right applications,

 

Btw.....S&S Cycle recommends mobil 1 v-twin only in their motors now.

 

I replied in your other thread, but in short... Mobil1 15w50 syn oil, not the V-twin stuff. 07 Ultra, 125,000 in 3 1/2 years. Florida heat, no problems. Never mind what so and so said he heard from someone's uncle who heard it from the cook at the local VFW who's brother in law works for Mobil. I am talking real world results. Proof is in the pudding.

 

Give Rotella T6 a try. It's approved for bikes and is heavy duty, unlike the Mobile 1 products. It endures high heat and has high shear strength. Besides my diesel truck, I run it in my bike and the Mercruiser in my boat.

 

You are absolutely correct. The v-twin oil meets the expensive JASO spec which is needed for shared sump bikes(jap). The regular 20w-50 is fine. The 15w-50 is a bit thinner at start up and will get to the top end quicker. And as already mentioned rotella t6 is great oil and even though it's a 5w-40 it stays a 40 weight(oil at operating temp) longer whereas a 20w-50 shears down to a 30 weight by the time 1500 miles comes along. So to recap our bikes do not need the over-priced JASO spec oils and any oil with the second number 50 will work fine.

 

What he said ^^^^^^^

 

Yes. Rotella is amazing oil and retains it's viscosity at temp for longer than bike oils. It has to meet incredible specs for cat and cummins. Use with confidence. Especially now that it's cooler the 5w-40 gets to the top end way faster than a 20w-50 can. Thereby there is less wear because the oil is there sooner on dry starts

 

+1 on Rotella T6.

 

Been running it in my V107T for over three years now. Would like to find an alternative, but over here in the UK the oils available to us are very different to your market. Mobil 1 V-Twin is darned expensive here!