one more question....

This is not meant to be an oil thread :)

I usually run Mobil1 synthetic oil in everything I own (except for the John Deere lawn tractor).

I have planned on running the Mobil1 20W-50 in my new WR and am concerned about the need for friction modifier additives. The service manual seems to say "non friction modified" I'm interpreting this to mean I should put in regular automotive type oils instead of the special motorcycle blend that Mobil1 sells (called MX4T and is 10W-40) which I believe includes friction modifiers.

The oil I have in mind is the Mobil1 "V-Twin 20W-50" blend which I believe does not have the friction modifier in it.

Without turning this in to the classic oil thread, can someone comment on 10W-40 vs 20W-40 vs 20W-50 (in hot Florida) and comment on this friction modifier thing mentioned in the manual?

Thanks in advance for any help!

Jerry in Deltona, FL



'01 WR426 - stock for now (except for the throttle stop mod and air box lid removed).


I am probably one of the few here, but I use true blue Yamalube. Your clutch is lubed by your motoroil and synthetics have been blamed (whether true or not) for causing clutch problems.

just my Opinion


I know some people have indeed had trouble with synthetics and their clutches. My street bike has over 140 RWHP, the stock clutch, and synthetic Mobil1, and never had any trouble with it (and I run that bike hard). Two other people I know had problems immediately upon dumping the SAME oil into their SAME bikes with less HP than me. I decided I'm going to continue to take my chances with the synthetics until I burn a clutch.



'01 WR426 - stock for now (except for the throttle stop mod and air box lid removed).

Jerry-don't use regular automotive oil in your bike! Almost all automotive oils contain friction modifiers for cold start-up protection,and they will,over time,fry your clutch.Stick with the synthetic.I have always used Amsoil 10W40 Motorcycle oil and have had zero with any of my bikes.Motul or Torco are other good choices.

I heard that mobil 1 15w-50 is the only mobil 1 safe to use.

...because it is the only "automotive" one without the friction modifiers. It's the one with the red cap, and it's a lot cheaper than the Mobil 1 motorcycle specific oils.

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