Just wondering general opinion on mixing brands and types of oils?
What im thinking is a synthetic oil for the engine ( not hd) and hd primary + in the primary? ?

 

I use Mobil 1 V-twin 20w50 in the engine and Formula+ in the primary. I've been contemplating switching to Mobil 1 gear oil in the primary. You'll get a lot of opinions here, but generally, as long as you don't have two different oils in the same hole, you're fine. And even then, it's usually not a problem. Most oils are compatible, I believe, it's just that the additives aren't always good together.

 

That is what I have done for years...primary does not know what is in the engine, and vice-versa. No problem.

 

[QUOTE=DK Custom;11814809]That is what I have done for years...primary does not know what is in the engine, and vice-versa. No problem.

What he said

 

There is no reason you can't do as you ask about, although personally I wouldn't use synthetic oils old chap, it just adds unnecessary expense. I do in my S&S big twin, as it is recommended. For a wide range of options take a look at Opie Oils (for UK members!). I plan on using Silkolene V-Twin synthetic, not least because its British!

 

I actually mixed oils in the engine this year:

I had HD dino 20w50 in the engine but during the hottest summer months (Southern California) I drained out 1 quart of the 20w50 and topped up with 1 quart of straight grade 70 dino.

Then come winter, I plan to replace all 3 quarts with 20w50 again.

Is that a bad thing to do?

 

OP is British. At the height of summer here it only ever gets mildly warm enough to take off our jackets, so our Harleys don't get stressed in the way some of you chaps suffer!

 

I've never seen anyone reccommend adding straight wt oil to a multi wt oil. In hotter climates where your riding temps are 80 °f and above I'd run a straight 60

 

OK, thanks for the info and the suggestion. I guess I should change back to straight 20w50 asap.

 

For you, run it. 20w-50 in the winter and straight 60 in the summer.