Radical oil suggestion--straight 40 wt.

My opinion on the air cooled bikes: NEVER use anything less than 20W50.

I run 20W50 year round (water cooled too) and don't have any problem even in freezing weather because I start the bike from the garage.

The bike I just bought had new 10W40 Honda oil and it would hardly shift when I was crossing the desert. It was as thin as water when I checked it.

The change to 20W50 in El Paso immediately fixed the shifting problem.

So: For hot summer riding, why not just switch to straight 40 weight?

I am not the only one suggesting it. Check out POWEROLL:


The only drawback I envision is you might need to wait 5 minutes while the bike warms up.

It makes sense to me. Has anybody done it? Please speak up?


it will just be too thick on startup and prolly have some problems with oil circulation. Not sure why you think straight weight oil would be any better, 20/50 works perfectly on air cooled bikes. Would not recommend changing different weight oils on bikes, use what the manufacturer recommends, ie 20/50 in winter on an water cooled bike that im sure 10/40 is what they say to use.

Even 20W50 is still built on 20W stock oil. Running all day at 250 deg F is working the modifiers to the max. From the Powroll pitch:


Specifically designed for use in harsh or high temperature conditions, this straight-weight oil will not break down, even under severe loads. A Micron Moly oil with 100% paraffin base and Soluble Moly added as a friction modifier.


Easier starting in cooler climates, but with heat resistant properties similar to our 40wt. Better pourability below 30 degrees. A great option for ice racing.

Running all day in the Texas summer heat is certainly "harsh" in my estimation. Since I don't purport to know more than Powroll, I will buy some and try it this summer. I will let everybody know how it works.


to each his own try it out and you tell us how well it works then. Me ill stick with the tried and proven 20/50 thats been used in the air cooled pigs for decades. Let us know how it works

It's becomes more important when using heavy springs and high lift cams.

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