I used nothing but synthetic in all 3 holes on my last new bike, and the same on this one...bottom line is the bikes run cooler and the oil doesn't break down nearly as quickly...I used H-D Syn 3 in my last bike, and Mobile 1 in my Train now...personally, I don't think brand has much to do with it if you're using a good quality syn and changing when necessary...

 

Synthetic oil is so much better, so why is there even a question as to what to use!

 

Can motor oil make an engine knock? I thought that was a fuel issue. I've been using Mobil 1 since the late '80s with no complaints. Straight 50 HD oil in the Panhead.

 

I vote Synthetic and I have been running Royal Purple in mine, all 3 holes. I don't know if it is a fact but it seems to run cooler than when I was running Mobil1, like I said don't know if it really does but if it makes me feel better about it and that's all that matters to me.

 

wheres my popcorn

 

drop in synthetic at the time of the first engine oil change in all 3 holes

 

Always synthetic except during break in. JMHO

 

IMHO.....

Synthetic in the Engine only.

Once... once I put syn in my primary and trans, the next day...after 15 minutes when everything was at operating temp the clutch started slipping in 5th gear, I thought my clutch was toast, I babied it back home. Called the dealer and talked to the parts guy, then called a different aftermarket shop. Both told me to switch back to the regular primary/trans oil asap. I Switched back to regular HD brand primary/trans oil and problem was solved and didn't even have to adjust anything. That was 5k miles ago...

IMHO... syn in the Engine only!

Just an experience I went through, not saying one oil is better than the other, just sharing what I went through.

 

Use Synthetic. The oil simply does not loose it's viscosity. Also it does not burn up like conventional oil, so you should not have to add any between changes.
You still got to change it (less) regularly, because of the normal wear debris.

I'm no expert, but have used the stuff for many years on some high milage vehicles.

 

I concur Mr. Bucketass!