Only reason I was going to change the tranny and primary at 5000 is b/c I was under the impression that with synthetic they could go longer (like 10,000 mile intervals), but didn't want to go that long. I figured if I cut the intervals in half and went 2500/5000 instead of 5000/10,000 that would be better.

 

WARG that sounds like a good plan, you are staying on top of it and you should be fine.

 

My personal belief is Harley changed the change interval for engine oil to satify the EPA. Makes it look like they are more efficiant and eviromentally friendly.

Nevertheless, It is an air cooled v-twin with loose tolerance, Has a fair amount of gas contamination to the oil like all air cooled engines. I will continue to run HD oil and change every 2500 miles and ride it till it dies, rebuild and do it over again.

Those that are so worried about oil and how long it is good for should just get a sample after, 1k, 3k 5k and 10k and send them in to be analyzed. this will tell you if the oil is holding up or not.

You can afford a bike of this price, a $45 oil change every 2500 mile wont kill you will it? Even if I ran Synthetic I would change this often, but thats another story.

 

Well many seem to overlook the MAIN advantage of a good Synthetic oil. That, IMO, is the heat resistance it affords. Good syn oil can go well over the 250 degrees F that breaks down dino oils. It just takes one really hot incident and your dino is cooked, 3K miles or ten miles, doesn't make a difference once it is heat oxidized and loses its viscosity rating and ability to protect the motor.

Add to that that syn oil actually runs cooler by around ten degrees or more and, to me at least, its a no brainer. With syn, changing more frequently than 5K intervals is a waste but won't hurt anything. With dino, it would probably be pretty foolish to go that long.

EZ