can we use auto oil in our bikes?

I was wondering this....when I got the bike, the previous owner said all he ever used was auto 10W 40....I did the same for the first oil change....then I used synthetic for a while and went back to motorcycle 10w-40 non synthetic oil. But I am wondering if I can use a regular high quality auto motor oil in the bike as well since it is a lot easier to buy when I need it. Any thoughts?

Post edited by: LP440, at: 2006/05/01 10:07

That is all I ever run in my bike is either penzoil or valoline 20w50 car oil and I have never had a problem and that is what my dad ran in this bike when he had it.

I use auto oil. Was using Castrol 10w-40, then switched to 20w-50 because it's HOT here in the summer. You don't want to use an Energy Conserving oil, which has additives to screw with your clutch. These oils have the "Star" symbol on it.

One thing about auto oils I have been reading about, is they don't hold up the viscosity as long as motorcycle-specific oils. From some tests I saw on the internet it broke down after about 1,500 miles, so I'm thinking the next time I change my oil it will be to Shell Rotella T, a 15w-50 oil designed for diesel engines. It seems to hold up very well and can last through to the 3,000 mile mark to change oil. Really tho, I have put about 3,500 on my bike since last summer, and am on my third oil change. I noticed a big difference in shifting when I put the 20w-50 in there, much smoother shifts.

There are theories that motorcycle oils are more suited for the combined engine and transmission and are more resistant to "gear shear". I noticed improved shifting last year after putting in Castrol Act-evo 10W-40 for the first time.

There are a lot of oil formulations out there and I'm not so sure that automotive oils are formulated for air cooled engines which can be quite severe service. I doubt I'll put enough miles on my bike to require changing oil more than once a year so the extra cost isn't too much of a deterent to me.

- Nate >>

Put castrol 20-w50 in three bikes for the hot weather and it's coming out. Since changing, the clutch drags on all three. Going back to plain old el-cheap 20-w50. Don't know about that rotella but from what I read is has almost the same formulation as the castrol.

Duck wrote:

... Don't know about that rotella...

You just can't beat the convenience of the big jug. I've been using RotellaT since my second oil change, and no problems. I have been tempted to try others though...

Biquetoast wrote:

Duck wrote:

... Don't know about that rotella...

You just can't beat the convenience of the big jug. I've been using RotellaT since my second oil change, and no problems. I have been tempted to try others though...

Is the Rotella T an auto or bike oil?

LP440 wrote:

Is the Rotella T an auto or bike oil?

Kinda niether...

It's actually for diesels. So it should be pretty rugged, right?


Post edited by: Biquetoast, at: 2006/05/01 11:23

and this stuff is fine for wet clutches??

Yes kx. The oil discusion has been done here many times and many will not talk about oil because it sometimes ends up in an argument. The general concensus seems to be that Shell Rotella is good juice, Castrol is good, and some guys use (whatever brand) auto oil. The main thing to remember is that these old bikes need straight dyno oil WITHOUT friction modifiers or other fancy monkey snot added to the oil. When you get this stuff, it usually makes your clutch slip. I went semi-synthetic for a while a couple of years ago and noticed my clutch slipping. But, whatever rocks yer boat. Ask 5 people and you'll likely get 5 diff. answers.

ok, so what i really want to know is whether the rotella has friction mods or not....is that a no?

kx_125_pilot wrote:

ok, so what i really want to know is whether the rotella has friction mods or not....is that a no?

Gas put that very well. But to answer this question specifically, no. No additives in the 'T.

I'm not sure about all Rotella oils, but the one I use (as pictured above) is nothing but liquified dinosaurs.