Amsoil experience
Elite HDF Member
Joined: Apr 2006
Posts: 3,948
Likes: 54
From: The Burgh
My own recent experience:
I have 9,000 miles on my 09 Ultra.
I did an oil change last Friday after 3,700 miles since the last one. The bike has only seen Amsoil 20W-50 since break-in.
I wanted to try a so-called high performance semi-synthetic oil called Brad Penn (formerly Kendall).
After some 300 miles using Brad Penn, I can tell without a doubt that the engine runs noticeably hotter than with Amsoil so I'm gonna go back to Amsoil ASAP.
Brad Penn is much cheaper than Amsoil (less than 5 bucks a quart), but now I know why. Not that it's an inferior oil, actually it's the contrary, but I haven't spent all these $$$ to make my bike run cooler to have it back to square 1 because of the oil.
I have 9,000 miles on my 09 Ultra.
I did an oil change last Friday after 3,700 miles since the last one. The bike has only seen Amsoil 20W-50 since break-in.
I wanted to try a so-called high performance semi-synthetic oil called Brad Penn (formerly Kendall).
After some 300 miles using Brad Penn, I can tell without a doubt that the engine runs noticeably hotter than with Amsoil so I'm gonna go back to Amsoil ASAP.
Brad Penn is much cheaper than Amsoil (less than 5 bucks a quart), but now I know why. Not that it's an inferior oil, actually it's the contrary, but I haven't spent all these $$$ to make my bike run cooler to have it back to square 1 because of the oil.
Elite HDF Member
Joined: Apr 2006
Posts: 3,948
Likes: 54
From: The Burgh
Yes and heat comes from friction too. Ever rubbed 2 sticks of wood to start a fire or got blisters on your feet?
What I also know is that I haven't changed anything on the bike except the oil and it runs hotter.
What I also know is that I haven't changed anything on the bike except the oil and it runs hotter.
Road Master
Joined: May 2008
Posts: 1,031
Likes: 4
From:
you're funny- whatever makes you happy!
If the amount of friction went up so dramatically from changing to the non magical oil that there was a noticeable increase in friction generated heat, the engine would wear out in a week. Use a little common sense and stop reading the ads.
If the amount of friction went up so dramatically from changing to the non magical oil that there was a noticeable increase in friction generated heat, the engine would wear out in a week. Use a little common sense and stop reading the ads.
Last edited by brunswickoh; Aug 10, 2010 at 10:08 AM.
Advanced
Joined: Jul 2007
Posts: 50
Likes: 0
From: Northern Wisconsin
I switched to BradPenn20/50 from Amsoil 20/50 and noticed a smoother running engine with "NO" heat increase maybe less heat if anything. Rode 150 miles yesterday in 90 degree weather no issues.
Advanced
Joined: Jul 2007
Posts: 50
Likes: 0
From: Northern Wisconsin
I forgot to mention with amsoil in engine had lifter noise coming out of third gear between 3500-4200. With BradPenn 20/50 no lifter noise, I did at first, now with 500 miles on this oil engine is runing smooth.
On these new bikes with cat Amsoil is breaking down due to the heat.
On these new bikes with cat Amsoil is breaking down due to the heat.
Road Captain
Joined: Dec 2009
Posts: 540
Likes: 3
From: Nooga, TN
And your point would be? Yes the heat comes from combustion and from friction. Now the “heat in the oil,” i.e. oil temperature is the equilibrium between the heat coming from the above sources and the ability to transfer this heat out to the environment. The equations involved are Q=UA∆T and Q=mcp∆T, the former giving the heat transfer rate across a solid component and the latter the heat transfer for convection or flowing fluid. Combustion heat is a constant or close to it for a given horsepower so the variables are the friction and the latter equation, with m or flow rate being the other variable. Typically the friction does not change a great deal, but can be reduced by oil with the major change being the flow rate or the ability of the oil to flow. Some oils are better at this than others and will cause a change in operating temperature. So, changing the oil will have an effect on the equilibrium temperature based on its ability to flow and its ability to slightly reduce friction. Amsoil flows very well and this is probably the main variable in the reduction in temp, as do many of the other synthetic oils. This ability to flow typically causes an increase in engine noise as noticed by some on the forum. This increase in noise or perceived increase in noise has nothing to do with the protection of components from wear. The other variable is the specific heat capacity (cp); this can also change depending on the base stock of the oil and the additive package. cp is the ability of the fluid to “absorb heat.”
This is not an endorsement of Amsoil, but a good synthetic is better for the engine and tranny. There are many good oils out there and all have some differences in their performance.
This is not an endorsement of Amsoil, but a good synthetic is better for the engine and tranny. There are many good oils out there and all have some differences in their performance.
Last edited by Spur56; Aug 10, 2010 at 12:01 PM.
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Elite HDF Member
Joined: Apr 2006
Posts: 3,948
Likes: 54
From: The Burgh
I forgot to mention with amsoil in engine had lifter noise coming out of third gear between 3500-4200. With BradPenn 20/50 no lifter noise, I did at first, now with 500 miles on this oil engine is runing smooth.
On these new bikes with cat Amsoil is breaking down due to the heat.
On these new bikes with cat Amsoil is breaking down due to the heat.
I know I'm not gonna hurt the engine with it anyway.
