Originally Posted by TimVipond
Lee - which oils and what have you noticed?
I ride when it is 20-30* out and have been out in the teens a fair bit.
As far as notice not sure what you mean.
I am very fussy about warm up and I don't care what anyone says, motors need to get warm and that includes oil. When it is 30 outside my Harley would have sat at idle 10 minuets at least, until I finished with outer garments, got all plugged in gear wise, and situated and stuff. I would then ride 16 miles in semi-city, stop and go traffic to work, and still only saw 170 or so on the oil temp.
And that was a Rev Performance 98" Nikasil jugs, forged pistons, Speeds Cam 615/585 lift, 10.8 compression.
What that taught me was that in the cold it takes a pretty good amount of time to heat oil, and in my opinion the Tranny would take much longer. That build is a cooker for an old style Big Twin.
So I warm the bike up a long time and ALWAYS used a full synthetic in my tranny. I also like synthetic for it's ability to cling on parts and pretty important in a gear box and now a FD also.
I have found no mater what flavor, synth or dino, the 10-40 was a good Winter oil and a good compromise for the thinning at start, and protection while running.
In the 98" after I got past 2000 miles (their recommendation for life time warranty on the Nikasil jugs to stay in force) I used strait 60W Amsoil Racing in the summer and 10w40 Winter. That 60W will quiet down that front exhaust valve a bit on a Harley, but wont cure it
A 5 W anything wont give me full warm protection IMHO, and 20w50 ain't going nowhere fast at 20-30 degrees.
Just think they are realistic weights for my area of the US where we have 4 distinct seasons.