I always use 10w 40 oil in my bike. Is it okay to use 20w 50. I live on long island,new york if you wanted to know the climate. Thanks

 

10W40 is perfect for summer weather in most of the country!

20W50 is only for the very nottest weather. I know NY can get hot sometimes, but we are talking about the kind of weather you would have if you lived in Las Vegas, Phoenix, or Palm Springs....and were stupid enough to ride during mid day.

Good idea to switch to a thinner oil like 10W30 or even 5W30, when and if you ride during cold weather.

 

I use Valvoline 10wt-40 in all my Chinese and Honda air cooled thumpers....It gets kinda hot here in the summer and I would never think of using 20wt-50..