I have preferred to use factory brand oil in all of my vehicles regardless of age or brand. Sometimes you're better off paying a little more for peace of mind. Better than learning the hard way that not all things are created equal.

 

Whatever you do, stay away from the so called 5 micron filter. The Sporty oiling system is speced at 12-15 psi. It's a flow based system instead of a pressure based system like the TC's. Most filter bypass valves don't open till 8 psi to begin with so it's very important that your filter flows good. If you don't mind spending the money, these are very high flow filters. I have one on my 06XL, and 08FXSTC. And according to Blackstone Labs, who does my UOA's, they filter extremely well. Prior to installing one on my 08 96ci. oil pressure at idle, engine hot was around 6 psi. After installation it jumped to 20 psi due to the increased flow throughout the system.

http://www.gopurepower.com/store/ite...em&itemKey=684

 

I dont think I understand. I dont know a hell of a lot about these engines and their oil systems and pumps but make my living using pressure washer pumps. I would think the physics are the same. You can increase pressure one of 2 ways, increase flow from the source (oil pump) or restrict flow downstream of the source. You said your idle pressure increased almost 3 fold just by changing the filter. How does it do that without restricting flow?

 

By increasing flow through the filter, it increases volume in the oil galleys throughout the motor. At idle through a restrictive filter the oil flow isn't sufficient enough to completly fill the galleys. Fill the galleys to capacity then you get your pressure increase.

 

Wow, sometimes what I read on this forum just leave me speechless.
Do people really believe that vehicle manufactures make oil?
Do you know that HD's motor oil is made by........... CITGO?
Do people really believe that at about the same price, HD's Citgo oil compares with the likes of Mobil-1, Amsoil, Redline, etc?

You'd get more peace of mind, if you learned something about oil. There's an entire Oil Section here on the forum.

 

I like Amsoil I makes me happy.

 

Im sorry, still doesnt make sense to me. According to my manual my bike has a gerotor pump which is a positive displacement pump. Positive displacement pumps pump a given amount of oil at a given rpm..............no matter what. So lets say (just pulling numbers out of my *** here) at 1000 rpm the pump produces 1 gal per minute of flow. If filter A is restrictive whether by design or a clog, the pressure will increase until the restriction is overcome, either through the filter media or a bypass. Either way, that 1 gpm is going to flow. If filter B is less restrictive it will need LESS pressure to overcome its resistance. This is exactly opposite of what your saying is happening with your bikes. Im also assuming that pressure is measured between the pump and filter, which it is on my bike, at least for the idiot light, I have no gauge.

Not trying to be argumentative, just trying to understand.

 

And if you go back and read you'll see I said that on my TC that is what happened. Your Sportster oil pump is a volume based, not pressure based. A Sporty pump doesn't even have a pressure relief spring in it.

 

I think this thread may just set the record for mis-information.

 

Ill accept that, I know even less about them