I had Dealer put in syn 3 in all three holes at 1000 miles.After that I will use Mobil1 in all three holes.Starts better in the hot or cold with synthetic.
If syn3 would hurt Your engine Harley would void warranties if used.I have synthetic in My car and lawn mower and Bike.Ran it for 30000 miles in 2012 Limited.Easy start and better mileage.It is slippery compared to regular oil so lubricates better.If it was no good nobody would use it.You know how word gets around.

 

A guy I met shortly after buying the 01 Sportster in 2004 and I got to talking. He used a full syn oil in all his landscaping business equipment and swore by it, with facts to back him up, so I switched to it as well.
When I bought the 05 Glide, it came with syn in all three and I continued doing that.
Definitely quieter and cooler running.

The 14 will get full syn as well. I've been trying to get to the 1,000 before May, ain't gonna make it.

 

Switched to Red Line at 700 miles in motor stuck with formula plus trans and primary.

 

Synthetic oil is not thinner. Same viscosity as dino oil

 

Just did my own fluid change on my FLHTK at 1000 miles... i did use SYN3 as i got a deal on it but typicaly use Mobile 1 v-twin, Redline Primary, and Redline Shockproof in the Transmission. Shifts better and easier to find neutral with Redline.

 

It sure seems thinner when you pour it out of the container. I think it's thinner at room temp but at operating temp it's the same.

Also, I have read that Mobil 1 V-twin is no longer truly 100% synthetic but is "synthetic compliant."

 

I've saw the difference in racing engines where we would get a single race out of main bearings using traditional oil, we switched to Mobil 1 the next season as a test for them and got 6 races and probably could have gone more had we not had a box of bearings we were supposed to be running. That was almost 30 years ago...once you see something like that it's hard to deny the benefits of synthetics and synthetic blends.

I went with the HD Syn at 1,000 miles, I do notice a little more valve train clatter, but it does shift so much easier.

 

Agreed. 20-50 is 20-50 whether synthetic or dino.

 

I have 2014 I'm going to use Dino harley oil for the 1000 and then switch to synthetic next spring. I want to break in a bit more than 1000 miles before switching.
Just my thoughts no rule cut in stone.
Hap

 

Just had my 1000mile service on my 14 sgs and had them use synthetic $350 was the damage . I now have a lot easier time finding neutral