Actually, diesel oil is accidentally good lubricant for motorcycle powerplants. I thought everyone knew that.
Something like Shell Rotella 5w/40 had or still has JASO MA specification, so it is even for motorcycles with wet clutch, transmission as well.
Except it is irrelevant in this case because traditionally HDs had separate lubrication systems for engine, transmission and primary. There might be powerplants like that from other makers, but vast majority has just one lubrication system, not three, and that dictates oil specifications.
So, HD engine oil has evidently not much to do with traditional "motorcycle oil" because requirements are vastly different. HDs have, at least, air cooled cylinders with big bores with necessary generous piston to cylinder clearance becouse that tend to run hot like fuck.
Diesel engines of semi truck have huge 130-160 mm bores, and under full power for 30 minutes or better climbing Independence Pass do run hot as fuck as well. It requires generous piston to cylinder clearance as well. Hence oil specifications.
So, diesel oil is better match, and on the top, is widely available. Walmart, truck stops, etc will have it. 24/7. Motorcycle dealers? Not so much.
I don't see anything surprising 8n what they suggest.
And you? You'll never admit you were wrong, so couple pages of Latino Bull Shit is coming next.🤪
On 2/15/2023 at 6:14 AM, superhawk996 said:
I found this interesting. My Harley manual states to only use Harley oil, of course. The surprising part is that it says if you need oil and can't find Harley oil you can use Diesel engine oil to get by on. Then, obviously, you need to change it as soon as possible so that it'll be back to pure Harley oil.
I was shocked that it suggests diesel oil instead of motorcycle oil. Why would Harley state diesel oil, could it be better than motorcycle spec oils? Then it hit me. I wonder if Harley only suggests the diesel oil alternative to avoid having you think about using some other brand of motorcycle oil instead of theirs. Like they're trying to convince you that those other oils are SO fuckin shitty that they're not even good enough to get you by in an emergency, but the diesel stuff that doesn't really belong in there is at least ok enough keep it alive till you can find Harley oil.
Not going to comment on the use of diesel as it seems to be covered but just a note on Harley oil. Basically, it’s crap based on independent comparison with many other brands. At our largest Harley dealer in this area, they of course carry HD oil but no one buys it. Reason is, they also carry Amsoil which has proven over and over through independent lab testing as well as real live riding to come out on top every time so that’s what bikers want. In fact Amsoil worked with HD to develop the 20-50 for the big V twin market. And no, I’m not connected to Amsoil but a long time user.
Motorcycle oil thread, because it's been too long.
in The Garage
Posted
Not going to comment on the use of diesel as it seems to be covered but just a note on Harley oil. Basically, it’s crap based on independent comparison with many other brands. At our largest Harley dealer in this area, they of course carry HD oil but no one buys it. Reason is, they also carry Amsoil which has proven over and over through independent lab testing as well as real live riding to come out on top every time so that’s what bikers want. In fact Amsoil worked with HD to develop the 20-50 for the big V twin market. And no, I’m not connected to Amsoil but a long time user.