If you guys read your owners Manuals or service manuals, You'll find Harley recommends 60w oil in environments over 80*f.

Harleys table for viscosity go's like this


below 40* 10w40
above 40* sae 20w50
above 60* sae 50
above 80* sae 60


That is right from the HD manual

 

For those of you who've used it, what are the oil pressure readings with straight 50W or 60W? I know in my '05 EGC I usually got about 34 PSI at full operating temp on the freeway with Amsoil 20W-50. What do you get with 60W?

 

I guess I am one of the lucky one I use Purple 20/50 right out of the auto parts
store. I have (4) bikes, the 03 king, 95 standard 04 sportster and 08 FB. Been running it in all bikes since new. I used to run the grease lighting OIL back in the day.
They no longer make it. My bikes run with the best, never an oil leak. These hot Florida days has set me back but not my bikes. just my 2cents