Synthetic oil
#31
Where does it say that gear oil is suitable as a replacement for the HD Formula + trans oil? That is all the owner's manual specifies and I can't seem to find the equivalent anywhere. If someone can point out what the specs of the Formula + oil are, I'd love to see it so I can make that decision. TIA
#32
Where does it say that gear oil is suitable as a replacement for the HD Formula + trans oil? That is all the owner's manual specifies and I can't seem to find the equivalent anywhere. If someone can point out what the specs of the Formula + oil are, I'd love to see it so I can make that decision. TIA
#34
Here's what I found, can't vouch for the accuracy:
Application: recommended for heavy-duty service in manual transmissions where the manufacturer normally recommends either engine oils or GL-1 lubricants.
Specific Gravity: 0.857
Pounds per Gallon: 7.14
Viscosity, ASTM D 445,
cSt at 40°C: 168.04
cSt at 100°C: 20.10
Viscosity Index, ASTM D 2270: 139
Brookfield Viscosity, ASTM D 2983,
cP at -26°C - 28,800
cP at -40°C - n/m
Pour Point, ASTM D 97, °F (°C): -60 (-51)
Flash Point, ASTM D 92, °F (°C): 507 (264)
Application: recommended for heavy-duty service in manual transmissions where the manufacturer normally recommends either engine oils or GL-1 lubricants.
Specific Gravity: 0.857
Pounds per Gallon: 7.14
Viscosity, ASTM D 445,
cSt at 40°C: 168.04
cSt at 100°C: 20.10
Viscosity Index, ASTM D 2270: 139
Brookfield Viscosity, ASTM D 2983,
cP at -26°C - 28,800
cP at -40°C - n/m
Pour Point, ASTM D 97, °F (°C): -60 (-51)
Flash Point, ASTM D 92, °F (°C): 507 (264)
#35
#36
#37
As far as those that use automotive oil,, for the clutch if it does not say "energy conserving" around the API circle on the back it should be OK. If it says "energy conserving" it might cause clutch issues.
I personally use Mobil 1 V-twin motorcycle oil in both holes.
Last edited by hig4s; 11-10-2011 at 10:33 AM.
#38
I would advise strongly AGAINST using the Mobil 1 gear oil in the Sportster transmission. I used it in my 2004 Sporty, and my wife's 2006. Had to replace the clutch in mine at 18k, and the clutch AND stator in hers at similar intervals. I think something in the Mobil 1 ate the brass rivets in the clutches and messed up the stator. No scientific proof, just my experience. Stick with Formula + is my advice.... (We both have Softails now, but I still use Formula + in the primaries and Spectro Platinum gear oil in the trannies)
#39
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I would advise strongly AGAINST using the Mobil 1 gear oil in the Sportster transmission. I used it in my 2004 Sporty, and my wife's 2006. Had to replace the clutch in mine at 18k, and the clutch AND stator in hers at similar intervals. I think something in the Mobil 1 ate the brass rivets in the clutches and messed up the stator. No scientific proof, just my experience. Stick with Formula + is my advice.... (We both have Softails now, but I still use Formula + in the primaries and Spectro Platinum gear oil in the trannies)
If you don't want to use Formula+ in the primary on your Big Twin, you can always use the Mobile 1 4T 10W-40 Racing Oil (it's in the motorcycle category right next to the V-Twin).