Yep, oil.
The manual states SAE50 oil for temps above 60F.

So much for synthetic.... I used synthetic 20W50, recommended by the dealer. why would they recommend synthetic when straight 50W is listed in the manual?

 

That's what I use, 50 wt. For those who reference the service manual, the issue is resolved. For all others, I would like to see their degree in engineering. And they don't recommend it because (1) they don't sell 50 wt anymore, (2) they get more income by selling multi-grade synthetic, and/or (3) they are going going with the flow of the ill-informed public perception/demand.

 

Could there be damage from using synthetic?

 

I highly doubt it since SE's come with synthetic from the factory

 

Fk no.

 

Still working on my 2nd degree, but 2-wheeler oil's a controversial topic and mostly personal preference. Also, don't read too much into the recommended engine oil table b/c note the manual states "Always use the proper grade of oil for the "lowest temp" expected. See the column where the lowest temps are listed and I'm sure most of us live in areas where the temp will be within their recommended "below/above" 40-degrees. If you live at the equator and are constantly above 80-degrees, get a barrel of SAE 50 or SAE 60 and knock yourself out.

 

Nobody really cares, use what you want and ride your bike.

As for myself, I make my own oil in the bathtub with a secret formula passed down from my Grandfather. A friend of a friend of his neighbors great uncle developed it back in the late 1860's in anticipation of the invention of the automobile and it works great. It only take about two hours to make a batch of 50 gallons and I can go one million miles between oil changes. Once the big three heard about it they started a campaign to ruin the guy that invented it. That's why no one has ever heard of it. I hope they don't get wind of this post and come after me now.

 

Tired of the valve train noise when really hot outside, I contacted Cameron at RedLine Oil and asked his opinion on their heavier 25W-60 for summertime use here in NC in my Road Glide .

Their website acknowledges that though they still recommend 20W-50 for Twin Cams, there are many owners who use the heavier stuff in bikes other than Shovels / Pans, the reason for the 25W-60 in the first place ( according to Redine.)

Apparently the wear caused by the heavier oil during warm up didn't justify the quieter valve train afforded by it when it's hot. He claimed that they had recorded premature wear from the heavier oils and that's why they steadfastly won't recommend it unless you live in Arizona.

I don't have the engineering degree but I suspect somebody at RedLine does, so based on their recommendation I stayed with 20W-50.

 

iron ***---i am with the government and i come to help you. we will give you lots of money for you to destroy that formula and never mention it again...that product would put too many people out of business and must be destroyed now!!

 

I used 50wt Valvoline VR1 all last summer and the bike ran great. Manual says if operating temps are 60* or higher 50wt is fine. In summer that's easily no problem even at night. This year I've been running the Valvoline 20W-50 Synthetic MC blend and plan to stick with that primarily because of it's ability to withstand heat better than dino.