Mineral 20W-50 Vs Fully Syn 15W-50

Discussion in 'Softail Models' started by PENFOLD636, Aug 31, 2011.

  1. PENFOLD636

    PENFOLD636 New Member

    Guys i'm looking for some advice.
    I've a 2008 Fatboy with only 5,000 Km on the clock.
    Its been run in on the Harley 20W-50 and i've had one service which again the Harley 20W-50 was used.

    I personally feel that using a 20W-50 lubricant in the Irish / British climate is not a good idea as its to heavy an oil and takes to long to get to a temperature that enables the oil to circulate properly at start up.

    I was looking to switch to Mobil Racing 4T 15W-50 but mentioning this to a dealership sends them into overdrive. The are totally against the idea of a bike that has been "run in" on a mineral oil being switched to a synthetic oil.
    Personally i can't understand this, this is certainly not the case for cars.
    They also claim that a 20W-50 engine oil perfect for our climate.

    Could anyone shed a bit of light on this ?
    Has anyone had any experience (good or bad) with changing oils ?

    Thanking you all in advance !
  2. Hoople

    Hoople Account Removed

    I have never been out of the United States. Help me understand what an Irish/British climate is like.
  3. glider

    glider Veteran Member

    There's no problem with switching to a synthetic oil except in very high mileage engines that haven't been very well maintained. Your 5K is just about broken in and should pose no problem. I would however stick with the 20/50 made for an air cooled engine instead of the 15/50 because the additives differ between the two. The multi viscosity is more than enough to handle your situation.

    Many topics as well as opinions on oils on the forum. Try a search and you will be reading for hours.
    Last edited: Aug 31, 2011
  4. fin_676

    fin_676 Experienced Member Staff Member Moderator Contributor

    Cold wet and miserable my oil temp never goes above 180 but i do use a 20/50

    I would not use a 15/50 that was formulated for use in a liquid cooled engine just let the bike idle for a wee while before setting off and take it easy for the first couple of miles

  5. Jack Klarich

    Jack Klarich Expert Member

    H D as done a lot of testing and 20-50 is the oil of choice for all EVO and Twin Cams:s You decide what brand Read the oil polls and good luck
  6. R.Bingham

    R.Bingham Active Member

    Absolutely nothing wrong with using Mobile 1 15w50 oil in the engine of your Harley. I know of a guy who put 156,000 miles on his 05 Wide Glide with no issues until a bolt in the cam chest broke a took out the motor. After he got a Re-manufactured engine under his extended warranty he has since put another 50,000 miles with absolutely no problems.

    There was a great write up in the July issue of Thunder press that did a break down of the essential additives in the motor oils we use for our Harleys.

    Here is a link to the article. Motorhead Memo: Oil Breakdown Thunder Press

    Mobile 1 15w50 has more Zinc and Phosphorous (which are the essential additives) than H-D Syn 3 and Amsoil V-Twin 20w50.
  7. oldhippie

    oldhippie Senior Member

    Big BUT in using M1 15W-50 is where it is bottled. The US bottled contains ZDDP but the Canadian bottled does not according to the MSDS info. Also the European product Mobil 1 Racing 15W-50 is not similar to either the US or Canadian versions of M1 15W50 and does not meet any of the diesel engine oil SAE CF rating.

    The pour point of the M1 VTwin 20W50 is -51 C, while the pour point for the Racing 4T 15W50 is -39 C. Harley's HD20W50 pours like molasses around the freezing temp. You'll have a very noticeable difference on cold temp startup just going to the M1 VTwin as compared to the HD oil.

    Unless you're riding at well under freezing temps, the M1 VTwin 20W50 will serve you well.
  8. R.Bingham

    R.Bingham Active Member

    The guy who used M1 15w50 exclusively for 200,000 plus miles lives in Calgary. I would assume that it is Canadian bottled M1.
  9. oldhippie

    oldhippie Senior Member

    And up until last year the Canadian bottled M1 15W50 MSDS noted the existance of ZDDP in the oil. The new MSDS shows no mention of ZDDP which leads me to believe they've changed the additive package.:small3d034:

    I'd like to find out what they've replaced the ZDDP with and if it's still as effective for our HD engines. Until I do, I'll use the US bottled M1 15W50 for my winter storage and the M1 VTwin for my longer midsummer riding.
  10. wilks3

    wilks3 Junior Member

    Vance & Hines takes care of those pesky cats!!! :D